Equipment front end module

Proposed is an EFEM configured to perform wafer transfer between a wafer storage device and process equipment. More particularly, proposed is an EFEM that prevents harmful gases inside a transfer chamber in which wafer transfer is performed from escaping out of the EFEM.

CROSS REFERENCE TO RELATED APPLICATION

The present application claims priority to Korean Patent Application No. 10-2020-0138086, filed Oct. 23, 2020, the entire contents of which is incorporated herein for all purposes by this reference.

BACKGROUND OF THE INVENTION

Field of the Invention

The present disclosure relates to an equipment front end module (EFEM) configured to perform wafer transfer between a wafer storage device and process equipment.

Description of the Related Art

In a semiconductor manufacturing process, wafers are processed in a clean room in order to improve yield and quality. However, as devices have become more highly integrated, circuits have become finer, and wafers have become larger, maintaining cleanness in the entire clean room has become difficult from both a technical and cost point of view.

Therefore, in recent years, the cleanliness only in a local space around wafers has been managed. For this purpose, a module called equipment front end module (EFEM) has been used for storing wafers in a sealed storage pod called a front-opening unified pod (FOUP), and performing wafer transfer between the FOUP and process equipment that processes the wafers.

Such an EFEM is configured such that a transfer chamber provided with a wafer transfer device is provided, and a load port to which the FOUP is coupled is connected to a first surface of the transfer chamber, and the process equipment is connected to a second surface of the transfer chamber. Accordingly, the wafer transfer device transfers wafers stored in the FOUP to the process equipment and transfers the wafers having been processed in the process equipment into a wafer storage device.

Examples of this EFEM have been disclosed in Korean Patent No. 10-1002949 (hereinafter referred to as ‘Patent Document 1’) and Korean Patent Application Publication No. 10-2015-0009421 (hereinafter referred to as ‘Patent Document 2’).

EFEMs disclosed in Patent Documents 1 and 2 are configured such that when wafers stored in a FOUP coupled to a load port are transferred by a robot arm in a transfer chamber, gases are supplied into the transfer chamber, whereby cleanliness in the transfer chamber is managed.

However, as the gases are supplied into the transfer chamber, the pressure inside the transfer chamber becomes higher than that outside the transfer chamber, thereby causing a problem in that the gases inside the transfer chamber may escape out of the transfer chamber.

In other words, as the EFEM is manufactured in a large size, even when the inside of the transfer chamber is sealed, a leak may occur in the transfer chamber.

Therefore, harmful gases including fumes inside the transfer chamber may escape out of the transfer chamber, with the result that contamination may occur outside the EFEM, and thus, there is a problem in that workers may be exposed to harmful gases.

DOCUMENTS OF RELATED ART

SUMMARY OF THE INVENTION

Accordingly, the present disclosure has been made keeping in mind the above problems occurring in the related art, and an objective of the present disclosure is to provide an EFEM that prevents harmful gases inside a transfer chamber in which wafer transfer from escaping out of the EFEM.

In order to achieve the above objective, according to one aspect of the present disclosure, there is provided an equipment front end module (EFEM), including: a transfer chamber in which wafers are transferred between a wafer storage device and process equipment, wherein there may be no direct gas flow between the transfer chamber and a vicinity of the EFEM.

Furthermore, gas inside the transfer chamber may be blocked from escaping out of the EFEM.

Furthermore, external gas outside the EFEM may be blocked from flowing into the transfer chamber.

Furthermore, the EFEM may further include at least one chamber provided between the transfer chamber and an outside of the EFEM, and configured to block gas inside the transfer chamber from escaping out of the EFEM while blocking external gas outside the EFEM from flowing into the transfer chamber.

Furthermore, the EFEM may further include at least one chamber provided between the transfer chamber and an outside of the EFEM, and configured such that a pressure therein is maintained lower than a lower pressure from among a pressure inside the transfer chamber and a pressure in the vicinity of the EFEM.

Furthermore, the EFEM may further include: at least one first chamber provided between the transfer chamber and an outside of the EFEM, and configured such that a pressure therein is maintained lower than a lower pressure from among a pressure inside the transfer chamber and a pressure outside the EFEM; and at least one second chamber provided between the transfer chamber and the outside of the EFEM, and configured such that a pressure therein is maintained higher than that inside the first chamber.

Furthermore, the EFEM may further include: at least one first chamber provided between the transfer chamber and an outside of the EFEM, and configured such that a pressure therein is maintained lower than a lower pressure from among a pressure inside the transfer chamber and a pressure outside the EFEM; and a second chamber provided between the first chamber and the outside of the EFEM, wherein a pressure inside the second chamber may be maintained lower than that outside the EFEM.

Furthermore, the EFEM may further include: at least one first chamber provided between the transfer chamber and an outside of the EFEM, and configured such that a pressure therein is maintained lower than a lower pressure from among a pressure inside the transfer chamber and a pressure outside the EFEM; and a plurality of second chambers provided between the first chamber and the outside of the EFEM, wherein a pressure inside an outermost second chamber from among the second chambers may be maintained lower than that outside the EFEM.

Furthermore, the EFEM may further include: at least one first chamber provided between the transfer chamber and an outside of the EFEM, and configured such that a pressure therein is maintained lower than a lower pressure from among a pressure inside the transfer chamber and a pressure outside the EFEM; and a second chamber provided between the first chamber and the transfer chamber, wherein a pressure inside the second chamber may be maintained lower than that inside the transfer chamber.

Furthermore, the EFEM may further include: at least one first chamber provided between the transfer chamber and an outside of the EFEM, and configured such that a pressure therein is maintained lower than a lower pressure from among a pressure inside the transfer chamber and a pressure outside the EFEM; and a plurality of second chambers provided between the first chamber and the transfer chamber, wherein a pressure inside an innermost second chamber from among the second chambers may be maintained lower than that inside the transfer chamber.

According to another aspect of the present disclosure, there is provided an equipment front end module (EFEM), including: a transfer chamber in which wafers are transferred between a wafer storage device and process equipment; a first chamber surrounding the transfer chamber at a position outside the transfer chamber; a transfer chamber supply part supplying gas to the transfer chamber; a transfer chamber exhaust part exhausting gas inside the transfer chamber; a first chamber exhaust part exhausting gas inside the first chamber; and a controller controlling an operation of at least one of the transfer chamber supply part, the transfer chamber exhaust part, and the first chamber exhaust part so that a pressure inside the first chamber is maintained lower than that inside the transfer chamber.

Furthermore, the EFEM may further include: a second chamber surrounding the first chamber at a position outside the first chamber; and a second chamber supply part supplying gas to the second chamber, wherein the transfer chamber supply part may communicate with the second chamber, and the controller may control an operation of at least one of the first chamber exhaust part and the second chamber supply part so that the pressure inside the first chamber may be maintained lower than that inside the second chamber.

Furthermore, the controller may control an operation of at least one of the second chamber supply part, the transfer chamber supply part, and the transfer chamber exhaust part so that the pressure inside the second chamber may be maintained higher than that inside the transfer chamber.

Furthermore, the EFEM may further include: a first opening allowing connection of a FOUP of the wafer storage device to the transfer chamber; a first door provided in the transfer chamber so as to open and close an inside of the first opening; and a first communication part openably provided in the first chamber, and configured, when an outside of the first opening is closed by a load port door of a load port for loading the wafer storage device and the inside of the first opening is closed by the first door, to allow communication of a space between the load port door and the first door with the first chamber by opening.

Furthermore, the EFEM may further include: a second chamber surrounding the first chamber at a position outside the first chamber; a second door openably provided between the first chamber and the second chamber so as to close a space between the first chamber and the second chamber in the first opening; and a second communication part openably provided in the second chamber, and configured, when the load port door, the first door, and the second door are closed, to allow communication of a space between the load port door and the second door in the first opening with the second chamber by opening.

Furthermore, the EFEM may further include: a second opening allowing connection of a load lock chamber of the process equipment to the transfer chamber; a third door provided in the transfer chamber so as to open and close an inside of the second opening; and a third communication part openably provided in the first chamber, and configured, when an outside of the second opening is closed by a load lock chamber door of the load lock chamber of the process equipment and the inside of the second opening is closed by the third door, to allow communication of a space between the load lock chamber door and the third door with the first chamber by opening.

Furthermore, the EFEM may further include: a second chamber surrounding the first chamber at a position outside the first chamber; a fourth door openably provided between the first chamber and the second chamber so as to close a space between the first chamber and the second chamber in the second opening; and a fourth communication part openably provided in the second chamber, and configured, when the load lock chamber door, the third door, and the fourth door are closed, to allow communication of a space between the load lock chamber door and the fourth door in the second opening with the second chamber by opening.

Furthermore, the EFEM may further include: a first opening allowing connection of a FOUP of the wafer storage device to the transfer chamber; and a first gap exhaust part provided in a vicinity of the first opening so that gas escaping through a gap between the FOUP and the first opening flows into the first chamber.

Furthermore, the EFEM may further include: a second opening allowing connection of a load lock chamber of the process equipment to the transfer chamber; and a second gap exhaust part provided in a vicinity of the second opening so that gas escaping through a gap between the load lock chamber and the second opening flows into the first chamber.

The EFEM according to the present disclosure as described above has the following effects.

By surrounding the outside of the transfer chamber with the first chamber in which the pressure therein is maintained at a low pressure, it is possible to effectively prevent harmful gases inside the transfer chamber from escaping out of the EFEM.

By surrounding the outside of the first chamber with the second chamber in which the pressure therein is maintained at a high pressure, it is possible to effectively prevent external air from flowing into the transfer chamber.

By surrounding the outside of the transfer chamber with the first chamber in which the pressure therein is maintained at a high pressure, it is possible to effectively prevent harmful gases inside the transfer chamber from escaping out of the EFEM.

By surrounding the outside of the first chamber with the second chamber in which the pressure therein is maintained at a low pressure, it is possible to effectively prevent external air from flowing into the transfer chamber.

Through the first and second doors and the first and second communication parts, when the connection of the wafer storage device to the EFEM is released, even in a region where the first opening exists, it is possible to prevent harmful gases inside the transfer chamber from escaping out of the EFEM, while blocking external air from flowing into the transfer chamber.

Through the third and fourth doors and the third and fourth communication parts, when the connection of the process equipment to the EFEM is released, even in a region where the second opening exists, it is possible to prevent harmful gases inside the transfer chamber from escaping out of the EFEM, while blocking external air from flowing into the transfer chamber.

As the first gap exhaust part and the second gap exhaust part are provided, it is possible to not only effectively prevent escape of gas through the gap between the FOUP and the first opening and escape of gas through the gap between the load lock chamber and the second opening, and but also to easily control the pressure inside the first chamber.

DETAILED DESCRIPTION OF THE INVENTION

Contents of the description below merely exemplify the principle of the present disclosure. Therefore, those of ordinary skill in the art may implement the theory of the disclosure and invent various apparatuses which are included within the concept and the scope of the disclosure even though it is not clearly explained or illustrated in the description. Furthermore, in principle, all the conditional terms and embodiments listed in this description are clearly intended for the purpose of understanding the concept of the disclosure, and one should understand that this disclosure is not limited the exemplary embodiments and the conditions.

The above described objectives, features, and advantages will be more apparent through the following detailed description related to the accompanying drawings, and thus those of ordinary skill in the art may easily implement the technical spirit of the disclosure.

The embodiments of the present disclosure will be described with reference to sectional views and/or perspective views which schematically illustrate ideal embodiments of the present disclosure. Thus, the embodiments should not be construed as limited to the particular shapes of regions illustrated herein but are to include deviations in shapes that result, for example, from manufacturing.

An EFEM according to the present disclosure is characterized in that the EFEM includes a transfer chamber in which wafers are transferred between a wafer storage device and process equipment, and there is no direct gas flow between the transfer chamber and the vicinity of the EFEM.

In the EFEM, gas inside the transfer chamber is blocked from escaping out of the EFEM.

In addition, in the EFEM, external gas outside the EFEM is blocked from flowing into the transfer chamber.

In order to implement the EFEM as above, the EFEM may include at least one chamber that is provided between the transfer chamber and the outside of the EFEM, and is configured to block gas inside the transfer chamber from escaping out of the EFEM while blocking external gas outside the EFEM from flowing into the transfer chamber.

In this case, the EFEM may include at least one chamber that is provided between the transfer chamber and the outside of the EFEM, and is configured such that the pressure therein is maintained lower than a lower pressure from among the pressure inside the transfer chamber and the pressure in the vicinity of the EFEM.

EFEM10According to a First Embodiment of the Present Disclosure

Hereinafter, an EFEM10according to the first embodiment of the present disclosure will be described with reference toFIGS. 1 to 5C.

FIG. 1is a schematic plan view illustrating that a wafer storage device is connected to a front side of an EFEM according to a first embodiment of the present disclosure, and process equipment is connected to a rear side thereof;FIG. 2is a side sectional view illustrating the EFEM according to the first embodiment of the present disclosure;FIG. 3is a side sectional view illustrating the flow of gas in a transfer chamber, a first chamber, and a second chamber of the EFEM according to the first embodiment of the present disclosure;FIG. 4is a side sectional view illustrating the flow of gas in the transfer chamber, the first chamber, and the second chamber of the EFEM according to the first embodiment of the present disclosure, in which a transfer chamber supply portion and a transfer chamber exhaust portion are modified; andFIGS. 5A to 5Care views illustrating the operations of a load port door, first and second doors, and first and second communication portions when connection of the wafer storage device connected to the EFEM according to the first embodiment of the present disclosure is released.

The EFEM10according to the first embodiment of the present disclosure may include: a transfer chamber100in which wafers are transferred between a wafer storage device20and process equipment30; a first opening150for allowing connection of a FOUP21of the wafer storage device20to the transfer chamber100; a second opening160for allowing connection of a load lock chamber31of the process equipment30to the transfer chamber100; a first chamber200surrounding the transfer chamber100at a position outside the transfer chamber100; a transfer chamber supply part110for supplying gas to the transfer chamber100; a transfer chamber exhaust part120for exhausting gas inside the transfer chamber100; a first chamber exhaust part220for exhausting gas inside the first chamber200; a second chamber300surrounding the first chamber200at a position outside the first chamber200; a second chamber supply part310for supplying gas to the second chamber300; a second chamber exhaust part (not illustrated) for exhausting gas inside the second chamber300; and a controller400for allowing the pressure inside the first chamber200to be maintained lower than that inside the transfer chamber100and that inside the second chamber300.

In the EFEM10according to the first embodiment of the present disclosure, the pressure inside the first chamber200is maintained lower than that inside the transfer chamber100and that in the vicinity of the EFEM10, so that gas inside the transfer chamber100is blocked from escaping out in the vicinity of the EFEM10.

The first chamber200is provided outside the transfer chamber100to surround at least a part of a transfer chamber-defining surface of the EFEM10.

In order to block gas inside the transfer chamber100from escaping out in the vicinity the EFEM10while blocking external gas in the vicinity of the EFEM10from flowing into the transfer chamber100, the transfer chamber100becomes a gaseous sealed space with the vicinity of the EFEM10so that gas exchange between the transfer chamber100and the vicinity of the EFEM10does not occur.

Gas supplied into the transfer chamber100for maintaining the pressure inside the transfer chamber100flows into the transfer chamber100separately from external gas in the vicinity of the EFEM10.

Gas exhausted out of the transfer chamber100for maintaining the pressure inside the transfer chamber100is exhausted out of the transfer chamber100separately from external gas in the vicinity of the EFEM10.

Gas flow inside the transfer chamber100may flow in an upstream manner from a lower portion of the transfer chamber100toward an upper portion of the transfer chamber100. In this case, gas may be supplied into the transfer chamber100by a plurality of supply holes110aformed in the lower portion of the transfer chamber100. In addition, gas may be exhausted out of the transfer chamber100by a plurality of exhaust holes120aformed in the upper portion of the transfer chamber100.

Hereinafter, the EFEM10according to the first embodiment of the present disclosure will be described in more detail.

First, the wafer storage device20and the process equipment30connected to the EFEM10will be described.

The gas inside the EFEM10denotes all gases inside the EFEM10including an inert gas which will be described later. The inert gas denotes gas such as nitrogen, argon, or the like.

A plurality of wafer storage devices20is arranged in connection to a front surface of the EFEM10.

Each of the wafer storage devices20includes a FOUP21for storing a wafer, and a load port22on which the FOUP21is coupled and loaded.

The FOUP21is open at a side thereof, and a plurality of wafers is received through the open side and stored in a vertical arrangement in the FOUP21. Therefore, when the wafers are transferred during each process in a wafer manufacturing process, the wafers can be easily transferred through the FOUP21.

The FOUP21is coupled and loaded on the load port22. Therefore, when the load port22is installed on the front surface of the EFEM10, the open side of the FOUP21communicates with the first opening150formed in a front surface of the transfer chamber100, whereby the FOUP21of the wafer storage device20and the transfer chamber100communicate with and are connected to each other.

When the FOUP21and the load port22are coupled to each other, gas is supplied into the FOUP21through a gas delivery part of the load port22, whereby cleanliness of the wafers stored in the FOUP21is managed separately.

A load port door22ais provided in the load port22to close the outside of the first opening150.

The load port door22ais opened when the FOUP21is connected to the transfer chamber100so that the open side of the FOUP21and the first opening150can easily communicate with each other.

The load port door22ais closed, when the connection between the FOUP21and the transfer chamber100is released, to close the outside of the first opening150, so that external air is prevented from entering the transfer chamber100, or gas in the transfer chamber100is prevented from escaping out of the EFEM10.

The process equipment30is connected to a rear surface of the EFEM10. In this case, the load lock chamber31of the process equipment30communicates with the second opening160formed in a rear surface of the transfer chamber100, so that the process equipment30communicates and is connected to the rear surface of the EFEM10.

A plurality of process equipment30may be connected to the rear surface of the EFEM10, and the process equipment30may have various configurations.

For example, the process equipment30is configured such that a process equipment transfer chamber32is installed adjacent to the load lock chamber31, and a plurality of process units33processing wafers is installed adjacent to the process equipment transfer chamber32.

A load lock chamber door31amay be installed between the load lock chamber31and a rear wall of the transfer chamber100. By opening and closing operation of the load lock chamber door31a, the transfer chamber100and the load lock chamber31can communicate with or can block each other.

The load lock chamber door31ais opened when the load lock chamber31is connected to the transfer chamber100so that an open side of the load lock chamber31and the second opening160can easily communicate with each other.

The load lock chamber door31ais closed, when the connection between the load lock chamber31and the transfer chamber100is released, to close the outside of the second opening160, so that external air is prevented from entering the transfer chamber100, or gas in the transfer chamber100is prevented from escaping out of the EFEM10.

A process equipment transfer chamber door32amay be installed between the process equipment transfer chamber32and each of the process units33. By opening operation of the respective process equipment transfer chamber doors32a, the process equipment transfer chamber32and the plurality of process units33can communicate with or can block each other.

The process equipment transfer chamber32may be provided with a process equipment transfer device34, so that wafer transfer is performed between the load lock chamber31and the plurality of process units33by using the process equipment transfer device34.

Hereinafter, the transfer chamber100of the EFEM10according to the first embodiment of the present disclosure will be described.

As illustrated inFIGS. 1 and 2, the transfer chamber100functions to provide a space in which wafer transfer is performed between the wafer storage devices20connected to the front surface of the EFEM10and the process equipment30connected to the rear surface of the EFEM10.

Such wafer transfer is performed by a transfer device140installed in the transfer chamber100.

The first chamber200is provided outside the transfer chamber100, and the second chamber300is provided outside the first chamber200.

Therefore, the transfer chamber100has a shape surrounded by the first chamber200, and the first chamber200has shape surrounded by the second chamber300.

In other words, the first chamber200has shape surrounding the transfer chamber100, and the second chamber300has a shape surrounding the first chamber200.

The first opening150for allowing connection of the FOUP21of the wafer storage device20thereto is provided in the front surface of the transfer chamber100.

The first opening150functions to allow connection of the FOUP21of the wafer storage device20to the transfer chamber100.

A plurality of first openings150may be provided, and the number of the first openings150is the same as that of the wafer storage devices20.

The second opening160for allowing connection of the load lock chamber31of the process equipment30thereto is provided in the rear surface of the transfer chamber100.

The second opening160functions to allow connection of the load lock chamber31of the process equipment30to the transfer chamber100.

A plurality of second openings160may be provided, and the number of the second openings160is the same as that of the process equipment30.

As the first and second openings150and160are provided in the front and rear surfaces of the transfer chamber100, an area of the transfer chamber100except for the first and second openings150and160is surrounded by the first chamber200and the second chamber300. In other words, the first and second chambers200and300surround an area of the outside of the transfer chamber100except for the first and second openings150and160.

This is because the FOUP21of the wafer storage device20is required to communicate with the transfer chamber100through the first opening150and because the load lock chamber31of the process equipment30is required to communicate with the transfer chamber100through the second opening160.

The transfer chamber100includes the transfer chamber supply part110for supplying gas into the transfer chamber100, and the transfer chamber exhaust part120for exhausting gas inside the transfer chamber100.

The transfer chamber supply part110communicates with the second chamber300.

The transfer chamber supply part110functions to supply gas supplied from an external supply part through the second chamber supply part310into the transfer chamber100through the second chamber300.

The gas supplied by the transfer chamber supply part110may include an inert gas such as nitrogen.

The transfer chamber exhaust part120functions to exhaust gas and foreign substances inside the transfer chamber100. The gas inside the transfer chamber100includes gas supplied by the transfer chamber supply part110and fumes generated from the wafers.

Therefore, the transfer chamber exhaust part120functions to exhaust gas supplied by the transfer chamber supply part110and fumes generated from the wafers.

As illustrated inFIGS. 1 to 3, the transfer chamber supply part110is provided at the lower portion of the transfer chamber100to supply gas in a direction from the lower portion to the upper portion of the transfer chamber100, and the transfer chamber exhaust part120is provided at the upper portion of the transfer chamber100to exhaust gas in a direction from the lower portion to the upper portion of the transfer chamber100.

A transfer chamber sensor130for sensing the pressure inside the transfer chamber100is provided inside the transfer chamber100.

As illustrated inFIG. 4, the EFEM according to the first embodiment of the present disclosure may be implemented as an EFEM10ain a form in which a transfer chamber supply part and a transfer chamber exhaust part are modified.

In this modified form of the EFEM10a, the transfer chamber supply part may be comprised of a plurality of supply holes110aformed in a lower inner surface of the transfer chamber100, and the transfer chamber exhaust part may be comprised of a plurality of exhaust holes110aformed in an upper inner surface of the transfer chamber100.

The plurality of supply holes110ais provided in the lower inner surface of the transfer chamber100to allow supply of gas into the transfer chamber100in a form in which gas is supplied from a surface.

The plurality of exhaust holes120ais provided in the upper inner surface of the transfer chamber100to allow exhaust of gas from inside the transfer chamber100to outside the transfer chamber100in a form in which gas is exhausted from a surface.

As above, as the plurality of supply holes110aand the plurality of exhaust holes120aare provided, an updraft of gas is created inside the transfer chamber100. Therefore, gas flow inside the transfer chamber100flows in an upstream manner.

As such, gas is exhausted through the plurality of exhaust holes120aalong with fumes of the wafers, so that cleanliness of the transfer chamber100is managed.

On the other hand, the transfer chamber supply part may be provided in an upper portion of the transfer chamber100, with a fan filter unit (FFU), and the transfer chamber exhaust part may be provided in a lower portion of the transfer chamber100to allow exhaust of gas supplied from the upper portion, so that gas may be supplied and exhausted through a downdraft. In other words, gas flow inside the transfer chamber100may flow in a downstream manner through the transfer chamber supply part.

Hereinafter, the first chamber200and the second chamber300of the EFEM10according to the first embodiment of the present disclosure will be described.

The first chamber200is disposed to surround the transfer chamber100at a position outside the transfer chamber100.

By the controller400, the pressure inside the first chamber200is maintained lower than that inside the transfer chamber100and that inside the second chamber300.

As above, as the pressure inside the first chamber200is maintained lower than that inside the transfer chamber100and that inside the second chamber300, gas escaping from the transfer chamber100due to a leak and gas escaping from the second chamber300flow into the first chamber200.

The first chamber exhaust part220functions to exhaust gas inside the first chamber200. Therefore, gas inside the first chamber200is exhausted out of the EFEM10by the first chamber exhaust part220.

The second chamber300is disposed to surround the first chamber200at a position outside the first chamber200.

The second chamber supply part310functions to supply gas supplied from the external supply part to the second chamber300.

The second chamber exhaust part may be provided in the second chamber300. The second chamber exhaust part functions to exhaust gas inside the second chamber300. Therefore, the controller400controls the pressure inside the second chamber300by controlling the second chamber supply part310and the second chamber exhaust part.

The second chamber supply part310and the second chamber exhaust part may be integrally formed. In other words, the second chamber supply part310and the second chamber exhaust part may be configured such that gas is selectively supplied and exhausted through one pipe.

By the controller400, the pressure inside the second chamber300is maintained higher than that inside the transfer chamber100and that inside the first chamber200. This is because high-pressure gas is continuously supplied to the second chamber300by the second chamber supply part310, so that the high-pressure gas flows inside the second chamber300.

The transfer chamber100, the first chamber200, and the second chamber300are configured as separate independent spaces.

Therefore, the EFEM10has a triple-wall structure in which the first chamber200surrounds the outside of the transfer chamber100while the second chamber300surrounds the outside of the first chamber200.

Gas flowing through an updraft, and fumes of the wafers flow inside the transfer chamber100.

Gas and fumes escaping from the transfer chamber100and gas escaping from the second chamber300flow inside the first chamber200.

High-pressure gas supplied by the second chamber supply part310flows inside the second chamber300.

A first chamber sensor230for sensing the pressure inside the first chamber200is provided inside the first chamber200.

A second chamber sensor330for sensing the pressure inside the second chamber300is provided inside the second chamber300.

Hereinafter, the controller400of the EFEM10according to the first embodiment of the present disclosure will be described.

The controller400functions to control the pressure inside each of the transfer chamber100, the first chamber200, and the second chamber300of the EFEM10.

It is preferable that the pressure inside each of the transfer chamber100, the first chamber200, and the second chamber300controlled by the controller400satisfies a relationship of ‘the pressure inside the second chamber300>the pressure inside the transfer chamber100>the pressure inside the first chamber200’.

The controller400is connected to the transfer chamber sensor130, the first chamber sensor230, the second chamber sensor330, the transfer chamber supply part110, the second chamber supply part310, the transfer chamber exhaust part120, the first chamber exhaust part220, and the second chamber exhaust part.

The controller400controls the operation of at least one of the transfer chamber supply part110, the transfer chamber exhaust part120, and the first chamber exhaust part220so that the pressure inside the first chamber200is maintained lower than that inside the transfer chamber100.

The controller400controls the operation of at least one of the first chamber exhaust part220, the second chamber supply part310, and the second chamber exhaust part so that the pressure inside the first chamber200is maintained lower than that inside the second chamber300.

In the controller400, a first set pressure range, a second set pressure range, and a third set pressure range are preset.

The first set pressure range is a pressure range value that is a reference for the pressure inside the transfer chamber100measured by the transfer chamber sensor130, the second set pressure range is a pressure range value that is a reference for the pressure inside the first chamber200measured by the first chamber sensor230, and the third set pressure range is a pressure range value that is a reference for the pressure inside the second chamber300measured by the second chamber sensor330.

Therefore, the first set pressure range, the second set pressure range, and the third set pressure range satisfy a relationship of ‘the third set pressure range>the first set pressure range>the second set pressure range’.

In addition, it is preferable that the pressure inside each of the first chamber200and the second chamber300and the pressure outside the EFEM10satisfy a relationship of ‘the pressure inside the second chamber300>the pressure outside the EFEM10>the pressure inside the transfer chamber100>the pressure inside the first chamber200’.

Therefore, the first set pressure range, the second set pressure range, the third set pressure range, and the pressure outside the EFEM10satisfy a relationship of ‘the third set pressure range>the pressure outside the EFEM10>the first set pressure range>the second set pressure range’.

As above, as the pressure inside the transfer chamber100is lower than that outside the EFEM10, the pressure inside the transfer chamber100is maintained lower than that in the vicinity of the EFEM10, so that gas inside the transfer chamber100is blocked from escaping out in the vicinity of the EFEM10.

The controller400controls at least one of the transfer chamber supply part110and the transfer chamber exhaust part120so that the pressure inside the transfer chamber100measured by the transfer chamber sensor130falls within the first set pressure range.

The controller400controls the first chamber exhaust part220so that the pressure inside the first chamber200measured by the first chamber sensor230falls within the second set pressure range.

The controller400controls at least one of the second chamber supply part310and the second chamber exhaust part so that the pressure inside the second chamber300measured by the second chamber sensor330falls within the third set pressure range.

Hereinafter, a method of controlling the pressure inside the transfer chamber100, the pressure inside the first chamber200, and the pressure inside the second chamber300by the controller400will be described with reference toFIGS. 2 and 3.

The controller400controls the second chamber supply part310in communication with the external supply part to allow supply of gas from the external supply part into the second chamber300.

In this case, the gas supplied by the external supply part and the second chamber supply part310is supplied at a high pressure.

The gas supplied into the second chamber300flows inside the second chamber300, so that the inside of the second chamber300is filled with high-pressure gas.

Therefore, fundamentally, the pressure inside the second chamber300is higher than that inside the first chamber200and that inside the transfer chamber100.

In addition, the controller400controls at least one of the second chamber supply part310and the second chamber exhaust part so that the pressure inside the second chamber300measured by the second chamber sensor330falls within the third set pressure range, whereby the pressure inside the second chamber300is maintained higher than that inside the first chamber200and that inside the transfer chamber100.

The controller400controls the transfer chamber supply part110in communication with the second chamber300to allow supply of gas from the second chamber300into the transfer chamber100.

The controller400controls the transfer chamber exhaust part120to allow exhaust of gas inside the transfer chamber100. Therefore, the gas supplied into the transfer chamber100forms an updraft, and is exhausted out of the EFEM10through the transfer chamber exhaust part120along with fumes generated from the wafers.

As above, as high-pressure gas is supplied into and exhausted out of the transfer chamber100, cleanliness of the transfer chamber100is managed.

In the first chamber200, the controller400controls the first chamber exhaust part220so that the pressure inside the first chamber200measured by the first chamber sensor230falls within the second set pressure range. Therefore, the pressure inside the first chamber200is always maintained at a low pressure.

The controller400controls the transfer chamber supply part110and the transfer chamber exhaust part120so that the pressure inside the transfer chamber100measured by the transfer chamber sensor130falls within the first set pressure range. Therefore, the pressure inside the transfer chamber100is always maintained higher than that inside the first chamber200.

By the control of the controller400as above, the pressure inside the transfer chamber100is maintained lower than that outside the EFEM10.

In addition, the controller400controls the second chamber supply part310and the second chamber exhaust part so that the pressure inside the second chamber300measured by the second chamber sensor330falls within the third set pressure range. Therefore, the pressure inside the second chamber300is always maintained higher than that inside the first chamber200.

As above, as the pressure inside the first chamber200is maintained lower than that inside the transfer chamber100and that inside the second chamber300, as illustrated by an arrow ‘L1’ inFIG. 3, gas and fumes inside the transfer chamber100may unintentionally escape through a fine leak in an outer surface of the transfer chamber100and flow into the first chamber200.

In addition, as illustrated by an arrow ‘L2’ inFIG. 3, gas and fumes inside the second chamber300may unintentionally escape through a fine leak in an inner surface of the second chamber300and flow into the first chamber200.

The fine leak denotes a leak generated due to assembly errors, manufacturing tolerances of parts, etc. when the transfer chamber100is formed, or a leak in an assembled portion for each part that is generated when the EFEM10is operated, and collectively refers to a leak generated unintentionally.

The reason for the generation of the fine leak is an increase in manufacturing cost. That is, a precise and reproducible manufacturing process is advantageous when manufacturing the transfer chamber100, but this manufacturing process causes an increase in manufacturing cost. Therefore, when a less precise manufacturing process is used, while manufacturing cost is reduced, unintended fine leaks may be caused.

In the EFEM10according to the first embodiment of the present disclosure, by always maintaining the pressure inside the first chamber200between the transfer chamber100and the second chamber300at a low pressure, gas escaping from the transfer chamber100and the second chamber300is guided to flow into the first chamber200, and all the gases inside the first chamber200are exhausted to the first chamber exhaust part220. Therefore, the EFEM10according to the first embodiment of the present disclosure can effectively prevent harmful gases such as fumes in the transfer chamber100from escaping out of the EFEM10.

In detail, in the case of an EFEM according to the related art, as a transfer chamber of the EFEM is manufactured in a large size, gas inside the transfer chamber escapes through a fine leak of the large transfer chamber of the EFEM, which causes a problem in that harmful gases escape out of the EFEM. Therefore, these harmful gases lead to many problems such as harming the health of workers. In order to solve such problems of the related art as above, the present disclosure employs the concept of using a pressure difference to allow guidance of gas escaping from the transfer chamber100to the first chamber200, which is an exhaust space, and exhausted outside, so that it is possible to effectively prevent escape of harmful gases inside the transfer chamber100to outside the EFEM10.

The EFEM10according to the first embodiment of the present disclosure includes a fine leak in the transfer chamber-defining surface, which was not unintended when the transfer chamber100is manufactured, so that gas escapes from the inside of the transfer chamber100to the first chamber200, i.e., a low-pressure chamber, through this fine leak.

The transfer chamber100may be manufactured by a precise manufacturing process so that there is no fine leak that causes an escape of gas. However, this manufacturing process leads to a rapid increase in manufacturing cost. Therefore, in the present disclosure, even when an unintended fine leak is caused by an imprecise manufacturing process, by using the pressure difference between the chambers, it is possible to prevent the escape of gas, thereby securing both a reduced manufacturing cost and an improved safety of the EFEM10.

In addition, by disposing the second chamber300, in which high-pressure gas always flows, to surround the first chamber200, it is possible to not only prevent harmful gases in the transfer chamber100from escaping out, but also effectively prevent atmospheric pressure, i.e., external air outside the EFEM10, from entering the transfer chamber100.

In particular, the second chamber300is a space in which high-pressure gas always flows, which is formed by using the fact that when gas is supplied from the external supply part, the gas is supplied in a high-pressure state. Therefore, due to the pressure difference, harmful gases in the transfer chamber100do not flow into the second chamber300.

In addition, since gas escaping from the second chamber300escapes into the first chamber200having a low pressure, the amount of gas escaping from the second chamber300out of the EFEM10is small. Moreover, even when the gas inside the second chamber300escapes out of the EFEM10, only clean gas flows inside the second chamber300, so that the outside of the EFEM10is not contaminated.

As above, in the EFEM10according to the first embodiment of the present disclosure, by the first chamber200and the second chamber300, gas inside the transfer chamber100does not escape out of the EFEM10, and at the same time, gas outside the EFEM10does not flow into the transfer chamber100. Therefore, the space inside the transfer chamber100forms a kind of independent space in which gas inflow and outflow with respect to the external space outside the EFEM10are blocked.

Each of the above-described transfer chamber supply part110, transfer chamber exhaust part120, first chamber exhaust part220, second chamber supply part310, and second chamber exhaust part may include a flow controller.

The flow controller is connected to the controller400.

The controller400operates the respective flow controllers according to the pressure inside the transfer chamber100, the pressure inside the first chamber200, and the pressure inside the second chamber300, thereby easily controlling the flow rate of gas supplied or exhausted from the transfer chamber supply part110, the transfer chamber exhaust part120, the first chamber exhaust part220, the second chamber supply part310, and the second chamber exhaust part.

Hereinafter, a first door151, a first communication part165, a second door152, and a second communication part166of the EFEM10according to the first embodiment of the present disclosure will be described.

As illustratedFIGS. 1, 2, 5A, 5B, and 5C, the EFEM10according to the first embodiment of the present disclosure may further include: the first door151provided in the transfer chamber100so as to open and close the inside of the first opening150; the first communication part165openably provided in the first chamber200, and configured, when the outside of the first opening150is closed by the load port door22aof the load port22for loading the wafer storage device20and the inside of the first opening150is closed by the first door151, to allow communication of a space S1between the load port door22aand the first door151with the first chamber200by opening; the second door152openably provided between the first chamber200and the second chamber300so as to close a space between the first chamber200and the second chamber300in the first opening150; and the second communication part166openably provided in the second chamber300, and configured, when the load port door22a, the first door151, and the second door152are closed, to allow communication of a space S2between the load port door22aand the second door152in the first opening150with the second chamber300by opening.

As illustrated inFIGS. 5A to 5C, the first door151is provided in the transfer chamber100to open and close the inside of the first opening150.

The second door152is openably provided between the first chamber200and the second chamber300in the first opening150so as to close the space between the first chamber200and the second chamber300in the first opening150.

The first door151and the second door152are connected to the controller400, and function, when the connection between the wafer storage device20and the EFEM10is released, to close the first opening150along with the load port door22a.

The first communication part165is openably provided in the first chamber200, and functions, when the outside of the first opening150is closed by the load port door22aof the load port22for loading the wafer storage device20and the inside of the first opening150is closed by the first door151, to allow communication of the space between the load port door22aand the first door151with the first chamber200by opening.

The second communication part166is openably provided in the second chamber300, and functions, when the load port door22a, the first door151, and the second door152are closed, to allow communication of the space S2between the load port door22aand the second door152in the first opening150with the second chamber300by opening.

When the load port door22a, the first door151, and the second door152are all closed, the first communication part165is opened to allow communication of the space S1between the first door151and the second door152with the first chamber200.

The load port door22a, the first door151, the second door152, the first communication part165, and the second communication part166are connected to the controller400.

The first communication part165includes a first opening/closing means165a, and the second communication part166includes a second opening/closing means166a.

Hereinafter, operations of the first door151, the second door152, the first communication part165, and the second communication part166will be described in detail with reference toFIGS. 5A to 5C.

In a state ofFIG. 5Ain which the wafer storage device20and the EFEM10are connected so that the FOUP21and the transfer chamber100communicate with each other by the first opening150, as illustrated inFIG. 5B, in order to release the connection between the wafer storage device20and the EFEM10, the FOUP21loaded on the load port22is moved rearward.

In this case, under control of the controller400, the load port door22acloses the outside of the first opening150, the first door151closes the inside of the first opening150, and the second door152closes the space between the first chamber200and the second chamber300in the first opening150.

Therefore, as illustrated inFIG. 5B, the first opening150is divided into the space S1between the first door151and the second door152, and the space S2between the second door152and the load port door22a.

Thereafter, as illustrated inFIG. 5C, the controller400controls the first communication part165to allow opening of the first opening/closing means165a, thereby allowing communication of the space S1between the first door151and the second door152with the first chamber200, and controls the second communication part166to allow opening of the second opening/closing means166a, thereby allowing the space S2between the second door152and the load port door22awith the second chamber300.

As above, as the load port door22a, the first door151, the second door152, the first communication part165, and the second communication part166are provided, when the connection of the wafer storage device20to the EFEM10is released, even in a region where the first opening150exists, the space S1between the first door151and the second door152communicates with the first chamber200, so that gas escaping from the transfer chamber100and the second chamber300can be effectively exhausted through the second chamber exhaust part. In addition, even in the region where the first opening150exists, the space S2between the second door152and the load port door22acommunicates with the second chamber300, so that external air can be prevented from flowing into the first chamber200.

Therefore, in the present disclosure, even when the connection of the wafer storage device20is released, it is possible to effectively prevent harmful gases inside the transfer chamber100from escaping out of the EFEM10in the region of the first opening150.

Hereinafter, a third door (not illustrated), a third communication part (not illustrated), a fourth door (not illustrated), and a fourth communication part (not illustrated) of the EFEM10according to the first embodiment of the present disclosure will be described.

As illustratedFIGS. 1 and 2, the EFEM10according to the first embodiment of the present disclosure may further include: the third door provided in the transfer chamber100so as to open and close the inside of the second opening160; the third communication part openably provided in the first chamber200, and configured, when the outside of the second opening160is closed by the load lock chamber door31aof the load lock chamber31of the process equipment30and the inside of the second opening160is closed by the third door, to allow communication of a space between the load lock chamber door31aand the third door with the first chamber200by opening; the fourth door openably provided between the first chamber200and the second chamber300so as to close a space between the first chamber200and the second chamber300in the second opening160; and the fourth communication part openably provided in the second chamber300, and configured, when the load lock chamber door31a, the third door, and the fourth door are closed, to allow communication of a space between the load lock chamber door31aand the fourth door in the second opening160with the second chamber300by opening.

The third door is provided in the transfer chamber100to open and close the inside of the second opening160.

The fourth door is openably provided between the first chamber200and the second chamber300in the second opening160so as to close the space between the first chamber200and the second chamber300in the second opening160.

The third door and the fourth door are connected to the controller400, and function, when the connection between the process equipment30and the EFEM10is released, to close the second opening160along with the load lock chamber door31a.

The third communication part is openably provided in the first chamber200, and functions, when the outside of the second opening160is closed by the load lock chamber door31aof the load lock chamber31of the process equipment30and the inside of the second opening160is closed by the third door, to allow communication of the space between the load lock chamber door31aand the third door with the first chamber200by opening.

The fourth communication part is openably provided in the second chamber300, and functions, when the load lock chamber door31a, the third door, and the fourth door are closed, to allow communication of the space between the load lock chamber door31aand the fourth door in the second opening160with the second chamber300by opening.

When the load lock chamber door31a, the third door, and the second door are all closed, the third communication part is opened to allow communication of the space between the third door and the fourth door with the first chamber200.

The load lock chamber door31a, the third door, the fourth door, the third communication part, and the fourth communication part are connected to the controller400.

The third communication part includes a third opening/closing means, and the fourth communication part includes a fourth opening/closing means.

Hereinafter, operations of the third door, the fourth door, the third communication part, and the fourth communication part will be described in detail.

In a state in which the process equipment30and the EFEM10are connected so that the load lock chamber31and the transfer chamber100communicate with each other by the second opening160, in order to release the connection between the wafer storage device20and the EFEM10, the load lock chamber door31acloses the outside of the second opening160.

In this case, the third door closes the inside of the second opening160, and the fourth door closes the space between the first chamber200and the second chamber300in the second opening160.

Therefore, the second opening160is divided into a space between the third door and the fourth door and a space between the fourth door and the load lock chamber door31a.

Thereafter, the controller400controls the third communication part to allow opening of the third opening/closing means, thereby allowing communication of the space between the third door and the fourth door with the first chamber200, and controls the fourth communication part to allow opening of the four opening/closing means, thereby allowing communication of the space between the fourth door and the load lock chamber door31awith the second chamber300.

As above, as the load lock chamber door31a, the third door, the fourth door, the third communication part, and the fourth communication part are provided, when the connection of the process equipment30to the EFEM10is released, even in a region where the second opening160exists, the space between the third door and the fourth door communicates with the first chamber200, so that gas escaping from the transfer chamber100and the second chamber300can be effectively exhausted through the second chamber exhaust part. In addition, even in the region where the second opening160exists, the space between the fourth door and the load lock chamber door31acommunicates with the second chamber300, so that external air can be prevented from flowing into the first chamber200.

Therefore, in the present disclosure, even when the connection of the process equipment30is released, it is possible to effectively prevent harmful gases inside the transfer chamber100from escaping out of the EFEM10in the region of the second opening160.

Hereinafter, a first gap exhaust part341and a second gap exhaust part342of the EFEM10according to the first embodiment of the present disclosure will be described.

As described above, even when escaped gas is exhausted through the second chamber300, gas and fumes inside the transfer chamber100may escape through a gap between the first opening150for allowing connection of the wafer storage device20to the EFEM10, and the FOUP21of the wafer storage device20, and a gap between the load lock chamber31for allowing connection of the process equipment30to the EFEM10, and the second opening160.

Therefore, in order to prevent this, as illustrated inFIG. 1, the EFEM10according to the first embodiment of the present disclosure may further include: the first gap exhaust part341provided in the vicinity of the first opening150so that gas escaping through the gap between the FOUP21and the first opening150flows into the first chamber200; and the second gap exhaust part342provided in the vicinity of the second opening160so that gas escaping through the gap between the load lock chamber31and the second opening160flows into the first chamber200.

Hereinafter, the first gap exhaust part341and the second gap exhaust part342will be described in detail.

The first gap exhaust part341is provided in the vicinity of the first opening150so as to effectively prevent gas from escaping through the gap between the FOUP21and the first opening150during the connection of the FOUP21of the wafer storage device20to the first opening150.

The first gap exhaust part341may be comprised of a plurality of exhaust holes or a plurality of slits arranged in the vicinity of the first opening150.

The first gap exhaust part341communicates with the first chamber200. Therefore, when a suction force is generated inside the first chamber200by the first chamber exhaust part220, external air and gas that unintentionally escapes through the gap between the FOUP21and the first opening150flow into the first chamber200through the first gap exhaust part341, and then are exhausted outside through the first chamber exhaust part220.

The second gap exhaust part342is provided in the vicinity of the second opening160so as to effectively prevent gas from escaping through the gap between the load lock chamber31and the second opening160during the connection of the load lock chamber31of the process equipment30to the second opening160.

The second gap exhaust part342may be comprised of a plurality of exhaust holes or a plurality of slits arranged in the vicinity of the first opening150.

The second gap exhaust part342communicates with the first chamber200. Therefore, when a suction force is generated inside the first chamber200by the first chamber exhaust part220, external air and gas that unintentionally escapes through the gap between the load lock chamber31and the second opening160flow into the first chamber200through the second gap exhaust part342, and then are exhausted outside through the first chamber exhaust part220.

As above, as the first gap exhaust part341and the second gap exhaust part342are provided, it is possible to not only effectively prevent escape of gas through the gap between the FOUP21and the first opening150and escape of gas through the gap between the load lock chamber31and the second opening160, and but also to easily control the pressure inside the first chamber200.

In detail, in a case where only the first chamber exhaust part220is provided in the first chamber200, when exhaust is continuously performed by the first chamber exhaust part220, the degree of vacuum inside the first chamber200increases. This is because when gas escapes from the transfer chamber100and the second chamber300, the gas escapes through a fine leak.

As above, when the degree of vacuum inside the first chamber200increases, it is difficult to control the pressure inside the first chamber200through the exhaust of the first chamber exhaust part220. Therefore, it is difficult to maintain the pressure inside the first chamber200within the second set pressure range. This requires the first chamber200to have a separate hole for communication with external air, etc. The separate hole may perform this function along with the above-described first gap exhaust part341and second gap exhaust part342communicating with the outside of the EFEM10.

The above-described EFEM10according to the first embodiment of the present disclosure may include: at least one first chamber200provided between the transfer chamber100and the outside of the EFEM10, and configured such that the pressure therein is maintained lower than a lower pressure from among the pressure inside the transfer chamber100and the pressure outside the EFEM10; and at least one second chamber300provided between the transfer chamber100and the outside of the EFEM10, and configured such that the pressure therein is maintained higher than that inside the first chamber200.

In addition, the EFEM10may include: at least one first chamber200provided between the transfer chamber100and the outside of the EFEM10, and configured such that the pressure therein is maintained lower than a lower pressure from among the pressure inside the transfer chamber100and the pressure outside the EFEM10; and a second chamber300provided between the first chamber200and the outside of the EFEM10. In this case, the pressure inside the second chamber300may be maintained lower than that outside the EFEM10.

In addition, the EFEM10may include: at least one first chamber200provided between the transfer chamber100and the outside of the EFEM10, and configured such that the pressure therein is maintained lower than a lower pressure from among the pressure inside the transfer chamber100and the pressure outside the EFEM10; and a plurality of second chambers300provided between the first chamber200and the outside of the EFEM10, wherein the pressure inside an outermost second chamber300from among the second chambers300may be maintained lower than that outside the EFEM10.

In addition, the EFEM10may include: at least one first chamber200provided between the transfer chamber100and the outside of the EFEM10, and configured such that the pressure therein is maintained lower than a lower pressure from among the pressure inside the transfer chamber100and the pressure outside the EFEM10; and a second chamber300provided between the first chamber200and the transfer chamber100, wherein the pressure inside the second chamber300may be maintained lower than that inside the transfer chamber100.

In addition, the EFEM10may include: at least one first chamber200provided between the transfer chamber100and the outside of the EFEM10, and configured such that the pressure therein is maintained lower than a lower pressure from among the pressure inside the transfer chamber100and the pressure outside the EFEM10; and a plurality of second chambers300provided between the first chamber200and the transfer chamber100, wherein the pressure inside an innermost second chamber300from among the second chambers300may be maintained lower than that inside the transfer chamber100.

EFEM10′ According to a Second Embodiment of the Present Disclosure

Hereinafter, an EFEM10′ according to the second embodiment of the present disclosure will be described with reference toFIGS. 6 and 7.

FIG. 6is a side sectional view illustrating an EFEM according to a second embodiment of the present disclosure, andFIG. 7is a side sectional view illustrating the flow of gas in a transfer chamber, a first chamber, and a second chamber of the EFEM according to the second embodiment of the present disclosure.

As illustrated inFIGS. 6 and 7, the EFEM10′ according to the second embodiment of the present disclosure may include: a transfer chamber100′ in which wafers are transferred between a wafer storage device20and process equipment30; a first opening150for allowing connection of a FOUP21of the wafer storage device20and the transfer chamber100′; a second opening160for allowing connection of a load lock chamber31of the process equipment30and the transfer chamber100′; a first chamber200′ surrounding the transfer chamber100′ at a position outside the transfer chamber100′; a transfer chamber supply part110′ for supplying gas to the transfer chamber100′; a transfer chamber exhaust part120for exhausting gas inside the transfer chamber100′; a first chamber supply part210′ for supplying gas into the first chamber200′; a first chamber exhaust part (not illustrated) for exhausting gas inside the first chamber200′; a second chamber300′ surrounding the first chamber200′ at a position outside the first chamber200′; a second chamber exhaust part320′ for exhausting gas inside the second chamber300′; and a controller400for allowing the pressure inside the first chamber200′ to be maintained higher than that inside the transfer chamber100′ and that inside the second chamber300′.

In the EFEM10′ according to the second embodiment of the present disclosure, the pressure inside the first chamber200′ is maintained higher than that inside the transfer chamber100′ and that in the vicinity of the EFEM10′, so that gas inside the transfer chamber100′ is blocked from escaping out in the vicinity of the EFEM10′.

The first chamber200′ is provided outside the transfer chamber100′ to surround at least a part of a transfer chamber-defining surface of the EFEM10′.

In order to block gas inside the transfer chamber100′ from escaping out in the vicinity of the EFEM10′ while blocking external gas in the vicinity of the EFEM10′ from flowing into the transfer chamber100′, the transfer chamber100′ becomes a gaseous sealed space with the vicinity of the EFEM10′ so that gas exchange between the transfer chamber100′ and the vicinity of the EFEM10′ does not occur.

Gas supplied into the transfer chamber100′ for maintaining the pressure inside the transfer chamber100′ flows into the transfer chamber100′ separately from external gas in the vicinity of the EFEM10′.

Gas exhausted out of the transfer chamber100′ for maintaining the pressure inside the transfer chamber100′ is exhausted out of the transfer chamber100′ separately from external gas in the vicinity of the EFEM10′.

Gas flow inside the transfer chamber100′ may flow in an upstream manner from a lower portion of the transfer chamber100′ toward an upper portion of the transfer chamber100′. In this case, gas may be supplied into the transfer chamber100′ by a plurality of supply holes110aformed in the lower portion of the transfer chamber100′. In addition, gas may be exhausted out of the transfer chamber100′ by a plurality of exhaust holes120aformed in the upper portion of the transfer chamber100′.

The EFEM10′ according to the second embodiment of the present disclosure differs from the EFEM10according to the first embodiment in that the pressure inside the first chamber200′ is maintained higher than that inside the second chamber300′ and that inside the transfer chamber100′. Therefore, this difference is mainly described, and the above-description of the EFEM10according to the first embodiment of the present disclosure may be applied to the remaining identical configurations.

Hereinafter, the transfer chamber100′ of the EFEM10′ according to the second embodiment of the present disclosure will be described.

As illustrated inFIGS. 6 and 7, the transfer chamber100′ includes the transfer chamber supply part110′ for supplying gas into the transfer chamber100′, and the transfer chamber exhaust part120for exhausting gas inside the transfer chamber100′.

The transfer chamber supply part110′ communicates with the first chamber200.

The transfer chamber supply part110′ functions to supply gas supplied from an external supply part through the first chamber supply part210′ into the transfer chamber100′ through the first chamber200′.

The gas supplied by the transfer chamber supply part110′ may include an inert gas such as nitrogen.

The transfer chamber exhaust part120functions to exhaust gas and foreign substances inside the transfer chamber100′. The gas inside the transfer chamber100′ includes gas supplied by the transfer chamber supply part110′ and fumes generated from the wafers.

Therefore, the transfer chamber exhaust part120functions to exhaust gas supplied by the transfer chamber supply part110′ and fumes generated from the wafers.

The transfer chamber supply part110′ is provided at the lower portion of the transfer chamber100′ to supply gas in a direction from the lower portion to the upper portion of the transfer chamber100′, and the transfer chamber exhaust part120is provided at the upper portion of the transfer chamber100′ to exhaust gas in a direction from the lower portion to the upper portion of the transfer chamber100′.

A transfer chamber sensor130for sensing the pressure inside the transfer chamber100′ is provided inside the transfer chamber100′.

Hereinafter, the first chamber200′ and the second chamber300′ of the EFEM10′ according to the second embodiment of the present disclosure will be described.

The first chamber200′ is disposed to surround the transfer chamber100′ at a position outside the transfer chamber100′.

The first chamber supply part210′ functions to supply gas supplied from the external supply part to the first chamber200′.

The first chamber exhaust part may be provided in the first chamber200′. The first chamber exhaust part functions to exhaust gas inside the first chamber200′. Therefore, the controller400controls the pressure inside the first chamber200′ by controlling the first chamber supply part210′ and the first chamber exhaust part.

The first chamber supply part210′ and the first chamber exhaust part may be integrally formed. In other words, the first chamber supply part210′ and the first chamber exhaust part may be configured such that gas is selectively supplied and exhausted through one pipe.

By the controller400, the pressure inside the first chamber200′ is maintained higher than that inside the transfer chamber100′ and that inside the second chamber300′. This is because high-pressure gas is continuously supplied to the first chamber200′ by the first chamber supply part210′, so that the high-pressure gas flows inside the first chamber200′.

By the controller400, the pressure inside the first chamber200′ is maintained higher than that inside the transfer chamber100′ and that inside the second chamber300′.

As above, as the pressure inside the first chamber200′ is maintained higher than that inside the transfer chamber100′ and that inside the second chamber300′, gas escaping from the transfer chamber100′ due to a leak do not flow into the first chamber200′.

The second chamber300′ is disposed to surround the first chamber200′ at a position outside the first chamber200′.

By the controller400, the pressure inside the second chamber300′ is maintained lower than that inside the transfer chamber100′ and that inside the first chamber200′.

As above, as the pressure inside the second chamber300′ is maintained lower than that inside the transfer chamber100′ and that inside the first chamber200′, gas escaping from the first chamber200′ due to a leak and gas flowing in from outside the EFEM10′ due to a leak flow inside the second chamber300′.

The second chamber exhaust part320′ functions to exhaust gas inside the second chamber300′. Therefore, gas inside the second chamber300′ is exhausted out of the EFEM10′ by the second chamber exhaust part320′.

The transfer chamber100′, the first chamber200′, and the second chamber300′ are configured as separate independent spaces.

Therefore, the EFEM10′ has a triple-wall structure in which the first chamber200′ surrounds the outside of the transfer chamber100′ while the second chamber300′ surrounds the outside of the first chamber200′.

Gas flowing through an updraft, and fumes of the wafers flow inside the transfer chamber100′.

High-pressure gas supplied by the first chamber supply part210′ flows inside the first chamber200′.

Gas escaping from the first chamber200′ and gas flowing in from outside the EFEM10′ flow inside the second chamber300′.

A first chamber sensor230for sensing the pressure inside the first chamber200′ is provided inside the first chamber200′.

A second chamber sensor330for sensing the pressure inside the second chamber300′ is provided inside the second chamber300′.

Hereinafter, the controller400of the EFEM10′ according to the second embodiment of the present disclosure will be described.

The controller400functions to control the pressure inside each of the transfer chamber100′, the first chamber200′, and the second chamber300′ of the EFEM10′.

It is preferable that the pressure inside each of the transfer chamber100′, the first chamber200′, and the second chamber300′ controlled by the controller400satisfies a relationship of ‘the pressure inside the first chamber200′>the pressure inside the transfer chamber100′>the pressure inside the second chamber300′’.

The controller400is connected to the transfer chamber sensor130, the first chamber sensor230, the second chamber sensor330, the transfer chamber supply part110′, the first chamber supply part210′, the transfer chamber exhaust part120, the first chamber exhaust part, and the second chamber exhaust part320′.

The controller400controls the operation of at least one of the transfer chamber supply part110′, the transfer chamber exhaust part120, and the first chamber supply part210′ so that the pressure inside the first chamber200′ is maintained higher than that inside the transfer chamber100′.

The controller400controls the operation of at least one of the first chamber supply part210′, the first chamber exhaust part, and the second chamber exhaust part320′ so that the pressure inside the first chamber200′ is maintained higher than that inside the second chamber300′.

In the controller400, a first set pressure range, a second set pressure range, and a third set pressure range are preset.

The first set pressure range is a pressure range value that is a reference for the pressure inside the transfer chamber100′ measured by the transfer chamber sensor130, the second set pressure range is a pressure range value that is a reference for the pressure inside the first chamber200′ measured by the first chamber sensor230, and the third set pressure range is a pressure range value that is a reference for the pressure inside the second chamber300′ measured by the second chamber sensor330.

Therefore, the first set pressure range, the second set pressure range, and the third set pressure range satisfy a relationship of ‘the second set pressure range>the first set pressure range>the third set pressure range’.

In addition, it is preferable that the pressure inside each of the first chamber200′ and the second chamber300′ and the pressure outside the EFEM10′ satisfy a relationship of ‘the pressure inside the first chamber200′>the pressure outside the EFEM10′>the pressure inside the transfer chamber100′>the pressure inside the second chamber300′’.

Therefore, the first set pressure range, the second set pressure range, the third set pressure range, and the pressure outside the EFEM10′ satisfy a relationship of ‘the second set pressure range>the pressure outside the EFEM10′>the first set pressure range>the third set pressure range’.

As above, as the pressure inside the transfer chamber100′ is lower than that outside the EFEM10′, the pressure inside the transfer chamber100′ is maintained lower than that in the vicinity of the EFEM10′, so that gas inside the transfer chamber100′ is blocked from escaping out in the vicinity of the EFEM10′.

The controller400controls at least one of the transfer chamber supply part110′ and the transfer chamber exhaust part120so that the pressure inside the transfer chamber100′ measured by the transfer chamber sensor130falls within the first set pressure range.

The controller400controls at least one of the first chamber supply part210′ and the first chamber exhaust part so that the pressure inside the first chamber200′ measured by the first chamber sensor230falls within the second set pressure range.

The controller400controls the second chamber exhaust part320′ so that the pressure inside the second chamber300′ measured by the second chamber sensor330falls within the third set pressure range.

Hereinafter, a method of controlling the pressure inside the transfer chamber100′, the pressure inside the first chamber200′, and the pressure inside the second chamber300′ by the controller400will be described with reference toFIGS. 6 and 7.

The controller400controls the first chamber supply part210′ in communication with the external supply part to allow supply of gas from the external supply part into the first chamber200′.

In this case, the gas supplied by the external supply part and the first chamber supply part210′ is supplied at a high pressure.

The gas supplied into the first chamber200′ flows inside the first chamber200′, so that the inside of the first chamber200′ is filled with high-pressure gas.

Therefore, fundamentally, the pressure inside the first chamber200′ is higher than that inside the second chamber300′ and that inside the transfer chamber100′.

In addition, the controller400controls at least one of the first chamber supply part210′ and the first chamber exhaust part so that the pressure inside the first chamber200′ measured by the first chamber sensor230falls within the second set pressure range, whereby the pressure inside the first chamber200′ is maintained higher than that inside the second chamber300′ and that inside the transfer chamber100′.

The controller400controls the transfer chamber supply part110′ in communication with the first chamber200′ to allow supply of gas from the first chamber200′ into the transfer chamber100′.

The controller400controls the transfer chamber exhaust part120to allow exhaust of gas inside the transfer chamber100′. Therefore, the gas supplied into the transfer chamber100′ forms an updraft, and is exhausted out of the EFEM10′ through the transfer chamber exhaust part120along with fumes generated from the wafers.

As above, as high-pressure gas is supplied into and exhausted out of the transfer chamber100′, cleanliness of the transfer chamber100′ is managed.

In the second chamber300′, the controller400controls the second chamber exhaust part320′ so that the pressure inside the second chamber300′ measured by the second chamber sensor330falls within the third set pressure range. Therefore, the pressure inside the second chamber300′ is always maintained at a low pressure.

The controller400controls the transfer chamber supply part110′ and the transfer chamber exhaust part120so that the pressure inside the transfer chamber100′ measured by the transfer chamber sensor130falls within the first set pressure range. Therefore, the pressure inside the transfer chamber100′ is always maintained higher than that inside the second chamber300′.

By the control of the controller400as above, the pressure inside the transfer chamber100′ is maintained lower than that outside the EFEM10′.

In addition, the controller400controls the first chamber supply part210′ and the first chamber exhaust part so that the pressure inside the first chamber200′ measured by the first chamber sensor230falls within the second set pressure range. Therefore, the pressure inside the first chamber200′ is always maintained higher than that inside the second chamber300′.

As above, as the pressure inside the first chamber200′ is maintained higher than that inside the transfer chamber100′ and that inside the second chamber300′, as illustrated by an arrow ‘L1′’ inFIG. 7, gas and fumes inside the first chamber200′ may unintentionally escape through a fine leak in an outer surface of the transfer chamber100′ and flow into the transfer chamber100′.

In addition, as illustrated by an arrow ‘L2′’ inFIG. 7, gas and fumes inside the first chamber200′ may unintentionally escape through a fine leak in an outer surface of the first chamber200′ and flow into the second chamber300′.

In addition, gas outside the EFEM10′ may unintentionally flow in through a fine leak in an outer surface of the second chamber300′ into the second chamber300′.

In the EFEM10′ according to the second embodiment of the present disclosure, by always maintaining the pressure inside the first chamber200′ between the transfer chamber100′ and the second chamber300′ at a high pressure, gas and fumes inside the transfer chamber100′ from escaping out, and by always maintaining the pressure of the second chamber300′, which is the outermost chamber, at a low pressure, gas outside the EFEM10′ and gas escaping from the first chamber200′ are guided to flow into the second chamber300′, and all the gases inside the second chamber300′ are exhausted to the second chamber exhaust part320′. Therefore, the EFEM10′ according to the second embodiment of the present disclosure can effectively prevent harmful gases such as fumes in the transfer chamber100′ from escaping out of the EFEM10′.

In detail, in the case of an EFEM according to the related art, as a transfer chamber of the EFEM is manufactured in a large size, gas inside the transfer chamber escapes through a fine leak of the large transfer chamber of the EFEM, which causes a problem in that harmful gases escape out of the EFEM. Therefore, these harmful gases lead to many problems such as harming the health of workers. In order to solve such problem of the related art, in the case of the second embodiment, escape of gas inside the transfer chamber100′ is prevented through the first chamber200′, which is a high-pressure space, and inflow of gas from outside the EFEM10′ into the transfer chamber100′ is blocked through the second chamber300′, which is an exhaust space. Therefore, it is possible to effectively prevent escape of harmful gases inside the transfer chamber100′ to outside the EFEM10′ according to the second embodiment of the present disclosure, while blocking external gas outside the EFEM10′ from flowing into the transfer chamber100′.

As above, in the EFEM10′ according to the second embodiment of the present disclosure, by the first chamber200′ and the second chamber300′, gas inside the transfer chamber100′ does not escape out of the EFEM10′, and at the same time, gas outside the EFEM10′ does not flow into the transfer chamber100′. Therefore, the space inside the transfer chamber100′ forms a kind of independent space in which gas inflow and outflow with respect to the external space outside the EFEM10′ are blocked.

Each of the above-described transfer chamber supply part110′, transfer chamber exhaust part120, first chamber supply part210′, first chamber exhaust part, and second chamber exhaust part320′ may include a flow controller.

The flow controller is connected to the controller400.

The controller400operates the respective flow controllers according to the pressure inside the transfer chamber100′, the pressure inside the first chamber200′, and the pressure inside the second chamber300′, thereby easily controlling the flow rate of gas supplied or exhausted from the transfer chamber supply part110′, the transfer chamber exhaust part120, the first chamber supply part210′, the first chamber exhaust part, and the second chamber exhaust part320′.

Although the exemplary embodiments of the present disclosure have been described for illustrative purposes, those skilled in the art will appreciate that various modifications, additions, and substitutions are possible, without departing from the scope and spirit of the disclosure as defined by the appended claims. Therefore, the scope of the disclosure should be determined on the basis of the descriptions in the appended claims.