Exhaust apparatus and substrate processing apparatus having an exhaust line with a first ring having at least one hole on a lateral side thereof placed in the exhaust line

An exhaust apparatus using a gas curtain instead of a mechanical opening/closing structure is provided. The exhaust apparatus includes: a first region; a second region connected to the first region; a third region connected to the first region; and a first gas line connected to the second region, wherein when gas is supplied to the first gas line, the first region does not communicate with the second region but communicates with the third region.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Patent Application No. 10-2016-0108380, filed on Aug. 25, 2016, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.

BACKGROUND

One or more embodiments relate to an exhaust apparatus, a substrate processing apparatus using the exhaust apparatus, and a thin film fabricating method using the exhaust apparatus, and more particularly, to an exhaust apparatus configured to selectively discharge gases, a substrate processing apparatus using the exhaust apparatus, and a thin film fabricating method using the exhaust apparatus.

2. Description of the Related Art

Along with the development of semiconductor technology, semiconductor substrate processing processes such as a deposition process or an etching process have become more intricate, and various chemical materials have been used as source materials. Thus, substrate processing apparatuses having various structures have been developed to process various source materials.

If different chemical materials having high reactivity are used as source materials, the operation of equipment may be affected by reaction byproducts. For example, reaction byproducts may remain in solid form in; reactors or exhaust lines. Such remaining solid matter may decrease the efficiency of exhaust systems and may cause internal components such as valves or pressure gauges to malfunction. In addition, such solid matter may remain in exhaust pumps or scrubbers configured to collect harmful chemicals before the harmful chemicals are discharged to the air. In this case, the operation of substrate processing apparatuses may stop, or the operation or productivity of substrate processing apparatuses may be negatively affected.

SUMMARY

One or more embodiments include an exhaust apparatus configured to prevent the formation of reaction byproducts by selectively discharging gases, a substrate processing apparatus using the exhaust apparatus, and a thin film fabricating method using the exhaust apparatus.

According to one or more embodiments, an exhaust apparatus (or a substrate processing apparatus) includes: a first region; a second region connected to the first region; a third region connected to the first region; and a first gas line connected to the second region, wherein when gas is supplied to the first gas line, the first region does not communicate with the second region but communicates with the third region.

The exhaust apparatus (or the substrate processing apparatus) may further include a second gas line connected to the third region, wherein when gas is supplied to the second gas line, the first region may not communicate with the third region but may communicate with the second region.

The first gas line and the second gas line may be connected to each other.

The exhaust apparatus (or the substrate processing apparatus) may further include a first gas supply ring placed in the second region, wherein the first gas supply ring may include at least one hole connected to the first gas line.

The exhaust apparatus (or the substrate processing apparatus) may further include a bypass line connected to the second region.

The exhaust apparatus (or the substrate processing apparatus) may further include a first gas supply ring placed in the second region, wherein the first gas supply ring may include: a first hole connected to the first gas line; and a second hole connected to the bypass line.

The first hole may be located between the second hole and the first region. When gas is supplied to the first gas line, gas from the first region may be discharged to the third region, and gas from the bypass line may be discharged to the second region.

Gas supplied through the first gas line may not react with gas supplied through the bypass line.

The first gas line may include a first opening/closing unit, the second gas line may include a second opening/closing unit, and the exhaust apparatus (or the substrate processing apparatus) may further include a controller configured to control the first and second opening/closing units.

The exhaust apparatus (or the substrate processing apparatus) may further include a gas analysis unit connected to at least one of the first region, the second region, and the third region, wherein the controller may communicate with the gas analysis unit and determine operation timing of the first and second opening/closing units.

According to one or more embodiments, an exhaust apparatus (or a substrate processing apparatus) includes: an upper plate; a body; at least one gas supply ring; a lower plate; a first sub-exhaust line; a second sub-exhaust line; and at least one purge gas supply path penetrating the body and connected to the gas supply ring.

At least one exhaust path branching off from the main exhaust line may be formed in the body, and the exhaust path may be connected with the first sub-exhaust line and the second sub-exhaust line.

The gas supply ring may be located between the exhaust path and the first sub-exhaust line or between the exhaust path and the second sub-exhaust line.

The exhaust apparatus (or the substrate processing apparatus) may further include at least one bypass gas supply path penetrating the body and connected to the gas supply ring.

The gas supply ring may include at least one gas hole in a lateral side thereof, wherein the at least one gas hole may include: an upper hole connected to the purge gas supply path; and a lower hole connected to the bypass gas supply path, wherein the exhaust apparatus (or the substrate processing apparatus) may further include a sealing measure between the upper hole and the lower hole.

Purge gas discharged to the exhaust path formed in the body through the purge gas supply path and the upper hole may form a gas curtain in the exhaust path.

Gas flowing to the exhaust path through the purge gas supply path and the upper hole of the gas supply ring may be an inert gas, and gas flowing to the exhaust path through the bypass gas supply path and the lower hole of the gas supply ring may be dichlorosilane (DCS, SiH2Cl2) gas or NH3gas.

The exhaust apparatus (or the substrate processing apparatus) may further include an anti-backflow device connected to the purge gas supply path.

According to one or more embodiments, a substrate processing apparatus includes: a gas supply unit; a reactor; an exhaust unit; and an exhaust pump unit, wherein the gas supply unit includes: at least one gas line through which gas is supplied to the reactor from the gas supply unit; a bypass line branching off from the gas line and connected to the exhaust unit; and a purge gas line connected from the gas supply unit to the exhaust unit.

The exhaust unit may include: a main exhaust line; an upper plate; a body; a gas supply ring; a lower plate; and at least one sub-exhaust line, wherein the main exhaust line may be connected to the reactor, and the sub-exhaust line may be connected to the exhaust pump unit.

The body may include at least one exhaust path formed in the body and branching off from the main exhaust line, and the exhaust path may be connected to the sub-exhaust line, wherein the gas supply ring may be located between the exhaust path and the sub-exhaust line.

The substrate processing apparatus may further include: at least one purge gas supply path penetrating the upper plate and the body and connected to the exhaust path and the gas supply ring; and at least one bypass supply path penetrating the body and connected to exhaust path and the gas supply ring, wherein the purge gas supply path may be connected to the purge gas line, and the bypass gas supply path may be connected to the bypass line.

The gas supply ring may include at least one hole at a lateral side of the body, wherein the at least one hole may include: an upper hole through which a purge gas from the purge gas supply path passes; and a lower hole through which a bypass gas from the bypass gas supply path passes.

The lower hole may be located between the upper hole and the lower plate.

According to one or more embodiments, a thin film fabricating method includes: a first step of supplying a source gas; a second step of purging the source gas; a third step of supplying a reaction gas; and a fourth step of supplying plasma, wherein the source gas, the reaction gas, and the plasma are sequentially supplied, and a first purge gas is continuously supplied to a reaction space while the source gas, the reaction gas, and the plasma are supplied.

During the second step of purging the source gas, the source gas and the first purge gas may be discharged through a first path of an exhaust unit, and a second purge gas may be supplied to a second path of the exhaust unit.

During the second step of purging the source gas, the second purge gas may form a gas curtain in the second path.

When one of the source gas and the reaction gas is supplied to a reactor, the other gas may be bypassed to the exhaust unit.

A path to which the bypassed gas is discharged may be different from a path to which gas discharged from the reactor is discharged.

During the first step of supplying the source gas, the source gas and the first purge gas may be supplied to the reaction space, and the reaction gas may be supplied to the second path of the exhaust unit.

During the second step of purging the source gas, the first purge gas may be supplied to the reaction space, the source gas may be supplied to the first path of the exhaust unit, and the reaction gas may be supplied to the second path of the exhaust unit.

A first flow rate of the first purge gas supplied during the first step of supplying the source gas may be lower than a second flow rate of the second purge gas supplied during the second step of purging the source gas.

During the third step of supplying the reaction gas and the fourth step of supplying the plasma, the reaction gas and the first purge gas may be supplied to the reaction space, and the source gas may be supplied to the first path of the exhaust unit.

During the third step of supplying the reaction gas and the fourth step of supplying the plasma, the second purge gas may be supplied to the first path of the exhaust unit.

According to one or more embodiments, a thin film fabricating method includes: discharging a first gas from a first region to a second region; and discharging a second gas from the first region to a third region, wherein during the discharging of the first gas, a third gas is supplied to the third region to form a gas curtain including the third gas in the third region, and during the discharging of the second gas, the third gas is supplied to the second region to form a gas curtain including the third gas in the second region.

DETAILED DESCRIPTION

Embodiments will now be described with reference to the accompanying drawings.

The inventive concept may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein; rather, these embodiments are provided to give a clear understanding of the inventive concept to those of ordinary skill in the art. That is, the embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the inventive concept to those of ordinary skill in the art.

In the following description, terms are used only for explaining specific embodiments while not limiting the inventive concept. The terms of a singular form may include plural forms unless referred to the contrary. The meaning of “comprise” and/or “comprising” specifies a shape, a fixed number, a step, a process, a member, an element, and/or a combination thereof but does not exclude other shapes, fixed numbers, steps, processes, members, elements, and/or combinations thereof. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.

It will be understood that, although the terms first, second, etc. may be used herein to describe various members, regions, and/or elements, these members, regions, and/or elements should not be limited by these terms. These terms are not used to denote a particular order, a positional relationship, or ratings of members, regions, or elements, but are only used to distinguish one member, region, or element from another member, region, or element. Thus, a first member, region, or element discussed below could be termed a second member, region, or element without departing from the teachings of the inventive concept.

Hereinafter, embodiments will be described with reference to the accompanying drawing. Shapes illustrated in the drawings may be varied according to various factors such as manufacturing methods and/or tolerances. That is, the embodiments are not limited to particular shapes illustrated in the drawings. Factors such as shape changes in manufacturing processes should be considered.

FIGS. 1 and 2are schematic views illustrating an exhaust apparatus according to an embodiment.

Referring toFIG. 1, the exhaust apparatus may include a first region110, a second region120, a third region130, a first gas line140, and a second gas line150.

The first region110, the second region120, and the third region130may be connected to each other and may extend in different directions. For example, the first region110may be a region of an exhaust path and may be connected to a main exhaust line. The second region120and the third region130may be other regions of the exhaust path and may be respectively connected to sub-exhaust lines branching off from the main exhaust line.

The first gas line140may be connected to the second region120and may have a function of determining whether the first region110and the second region120communicate with each other. Herein, the term or expression “communication” or “communicate with” may be used to indicate the possibility of exchange of flow of gas. For example, when the first region110communicates with the second region120, gas may flow from the first region110to the second region120and from the second region120to the first region110.

The second gas line150may be connected to the third region130and may have a function of determining whether the first region110and the second region130communicate with each other. For example, if gas is supplied to the first gas line140, the first region110may not communicate with the second region120but may communicate with the third region130(refer toFIG. 1). In addition, if gas is supplied to the second gas line150, the first region110may not communicate with the third region130but may communicate with the second region120(refer toFIG. 2).

In the exhaust apparatus, many kinds of gases may be supplied to the first region110. Such gases may be selectively discharged to the second region120or the third region130. For example, when gas is supplied to the first gas line140, since the first region110communicates with the third region130, gas (for example, a first gas) of the first region110may be discharged to the third region130. However, when gas is supplied to the second gas line150, since the first region110communicates with the second region120, gas (for example, a second gas) of the first region110may be discharged to the second region120.

The current embodiment relates to an exhaust line structure including a plurality of exhaust lines. In the current embodiment, gas lines are used to individually discharge at least two source gases. Such a gas line supplies gas having low reactivity (for example, an inert gas such as argon (Ar)) to an exhaust line to form a gas curtain in the exhaust line. Then, the exhaust line is substantially closed, and thus a particular gas may be selectively discharged.

Referring toFIG. 1, the first region110communicates with the third region130, and thus a first gas is discharged from the first region110to the third region130by a pump B. Gas supplied to the second region120through the first gas line140is discharged from the second region120by a pump A. In other words, a gas having low reactivity with the first gas is supplied to the second region120, and thus a gas curtain including the gas is formed in the second region120.

Referring toFIG. 2, the first region110communicates with the second region120, and thus a second gas is discharged from the first region110to the second region120by the pump A. Gas supplied to the third region130through the second gas line150is discharged from the third region130by the pump B. In other words, a gas having low reactivity with the second gas is supplied to the third region130, and thus a gas curtain including the gas is formed in the third region130.

As described above, the first region110may be adjacent to the main exhaust line, and the second region120and the third region130may respectively be adjacent to a first sub-exhaust line and a second sub-exhaust line. Therefore, gases supplied through the first gas line140and the second gas line150may respectively form gas curtains in entrances of the first and second sub-exhaust lines, and thus it may be possible to selectively discharge gases. In some embodiments, the flow rates of gases supplied through the first gas line140and/or the second gas line150may be maintained to be substantially equal to the flow rate of gas flowing out from a reactor.

As described above, the current embodiment provides a gas-based opening/closing structure that enables fast switching compared to a mechanical opening/closing structure. For example, fast switching between gases may be required in an atomic layer deposition process. However, if a mechanical opening/closing structure (for example, a flapper valve) is used in such an atomic layer deposition process, it may be difficult to control the atomic layer deposition process according to the required short gas exchange intervals because of limitations in mechanical operations. In addition, mechanical opening/closing structures are likely to break down or malfunction because of frequent physical operations.

However, the embodiment provides an opening/closing structure using a gas curtain instead of using a mechanical structure, thereby guaranteeing high speed operations. In addition, problems such as mechanical abrasion may not occur in the gas-based opening/closing structure of the embodiment. Thus, the gas-based opening/closing structure may have an infinite lifespan, and the durability of the exhaust apparatus having the gas-based opening/closing structure may be improved. Materials remaining after chemical reactions may accumulate on such mechanical opening/closing structures. However, such remaining materials may not accumulate on the gas-based opening/closing structure of the embodiment, and thus problems relating to such remaining materials may not occur. In addition, the gas-based opening/closing structure does not require an additional structure in exhaust lines, and thus a space for maintenance/repair may easily be ensured in the exhaust lines. That is, improvements may be made in terms of maintenance/repair.

The embodiment may have positive technical effects (for example, allowing rapid gas exchange and preventing inefficient operations of equipment caused by reaction byproducts) on atomic layer deposition processes such as a silicon nitride atomic layer deposition process in which dichlorosilane (DCS: SiH2Cl2) and NH3are used as source materials. This will be described hereinafter.

FIG. 3is a schematic view illustrating a substrate processing apparatus according to an embodiment. The substrate processing apparatus of the current embodiment may be configured using the exhaust apparatus of the previous embodiment. Thus, the same description as that presented in the previous embodiment will not be presented here.

Referring toFIG. 3, the substrate processing apparatus may include a gas supply unit210, a reactor220, an exhaust unit230, a controller240, and gas analysis units250. The substrate processing apparatus may further include exhaust pumps (not shown) connected to the exhaust unit230(refer toFIGS. 1 and 2).

The gas supply unit210may supply at least two source gases and/or a first purge gas to the reactor220through at least one reaction gas line260. The gas supply unit210may be connected to a showerhead configured to supply gas to a substrate in a vertical direction. In another embodiment, the gas supply unit210may be connected to a lateral-flow device configured to supply gas in a lateral direction. In another embodiment, the gas supply unit210may be connected to any device configured to supply gas to a reaction space.

A first gas line140and a second gas line150may be connected to each other, and the gas supply unit210may supply a second purge gas to the first gas line140and/or the second gas line150through a purge gas line265. In addition, the substrate processing apparatus may further include a bypass line (not shown) branching off from the reaction gas line260and joining the exhaust unit230. Therefore, source gases and/or a first purge gas may be directly supplied from the gas supply unit210to the exhaust unit230through the bypass line (refer toFIG. 6).

The exhaust unit230may selectively discharge gases received from the reactor220. For example, as described above, the exhaust unit230may include a main exhaust line270connected to a first region, a first sub-exhaust line280connected to a second region, a second sub-exhaust line290connected to a third region, the first gas line140, and the second gas line150.

The first gas line140may include a first opening/closing unit310. In addition, the second gas line150may include a second opening/closing unit320. A purge gas may be supplied from the gas supply unit210to the first sub-exhaust line280and/or the second sub-exhaust line290depending on whether the first opening/closing unit310and/or the second opening/closing unit320are/is opened or closed.

The controller240may control the first opening/closing unit310and/or the second opening/closing unit320. For example, the controller240may communicate with the analysis units250to determine operation timing of the first opening/closing unit310and/or the second opening/closing unit320.

The analysis units250may analyze the compositions or properties of gases (for example, the components, temperatures, flow rates, pressures, or concentrations of gases). The analysis units250may be connected to at least one of the gas supply unit210, the reaction gas line260, the main exhaust line270connected to the first region, the first sub-exhaust line280connected to the second region, and the second sub-exhaust line290connected to the third region.

The controller240may communicate with the analysis units250to determine a time period during which gas reaches from the gas supply unit210to the first sub-exhaust line280(or the second sub-exhaust line290). Then, the first opening/closing unit310or the second opening/closing unit320may be opened or closed based on the determined time period. Based on the operations of the first opening/closing unit310and the second opening/closing unit320, a second purge gas may be supplied to the first sub-exhaust line280or the second sub-exhaust line290to form a gas curtain. As a result, source gases supplied from the gas supply unit210may be selectively discharged.

FIGS. 4 and 5are schematic views illustrating a substrate processing apparatus including an exhaust apparatus according to another embodiment. The exhaust apparatus and the substrate processing apparatus of the current embodiment may be modifications of the exhaust apparatus and the substrate processing apparatus of the previous embodiments. Thus, the same description as that presented in the previous embodiments will not be presented here.

Referring toFIGS. 4 and 5, the substrate processing apparatus may include a first discharge part144, a second discharge part146, a reaction chamber106, and the exhaust apparatus134. The exhaust apparatus134may include a first region110, a second region120, a third region130, a first gas line140connected to the second region120, and a second gas line150connected to the third region130.

The substrate processing apparatus may be a lateral-flow type substrate processing apparatus configured to supply gas in a lateral direction and discharge the gas through the exhaust apparatus134. For example, a first gas (for example, a deposition or cleaning gas) may be supplied to the reaction chamber106through the first discharge part144. In this case, the exhaust apparatus134may be operated such that gas flowing in the reaction chamber106may be discharged through the third region130.

For example, the exhaust apparatus134may supply a low-reactivity gas (and the first gas) to the first gas line140. In this case, the first region110does not communicate with the second region120owing to the low-reactivity gas but communicates with the third region130. Therefore, the first gas supplied through the first discharge part144may be discharged through only the third region130.

Referring toFIG. 5, a second gas may be supplied to the reaction chamber106through the second discharge part146. In this case, the exhaust apparatus134may be operated such that gas flowing in the reaction chamber106may be discharged through the second region120.

For example, the exhaust apparatus134may supply a low-reactivity gas (and the second gas) to the second gas line150. In this case, the first region110does not communicate with the third region130owing to the low-reactivity gas but communicates with the second region120. Therefore, the second gas supplied through the second discharge part146may be discharged through only the second region120.

FIG. 6is a schematic view illustrating a substrate processing apparatus including an exhaust apparatus C according to another embodiment. The exhaust apparatus C and the substrate processing apparatus of the current embodiment may be modifications of the exhaust apparatuses and the substrate processing apparatuses of the previous embodiments. Thus, the same description as that presented in the previous embodiments will not be presented here.

Referring toFIG. 6, like in the previous embodiments, the substrate processing apparatus may include a gas supply unit, a reactor1, the exhaust apparatus C, a first pump3, a first scrubber11, a second pump4, and a second scrubber12. The substrate processing apparatus may be configured to supply gas to a substrate using a gas injection unit2in a direction perpendicular to the substrate.

For example, the substrate processing apparatus illustrated inFIG. 6may be an atomic layer deposition apparatus configured to form a silicon nitride film. In the current embodiment, DCS (Dichlorosilane; SiH2Cl2) is used as a silicon source, and ammonia (NH3) is used as a nitrogen source. The atomic layer deposition apparatus (substrate processing apparatus) of the current embodiment may include the reactor1, the gas injection unit2, the first pump (DCS exhaust pump)3, the second pump (NH3exhaust pump)4, a main exhaust line5, a DCS sub-exhaust line6, a NH3sub-exhaust line7, a DCS bypass line8, an NH3bypass line9, a purge argon line10, the first scrubber (DCS scrubber)11, and the second scrubber (NH3scrubber)12. In addition, the atomic layer deposition apparatus may further include valves v1to v11to control flows of gases in lines.

The reactor1may provide a space (for example, a closed space) in which a silicon nitride thin film is deposited on a substrate. To this end, the reactor1may be isolated from the outside of the reactor1using a sealing measure such as an O-ring. In general, the reactor1may be maintained at a pressure equal to or lower than atmospheric pressure. A substrate support or susceptor (not shown) may be placed in the reactor1, and a gate valve (not shown) may be located at a lateral side of the reactor1to introduce and discharge substrates therethrough. The gate valve may be opened only when a substrate is introduced or discharged through the gate valve and may be maintained in a closed state during a process.

DCS and NH3supplied through a DCS line19and an NH3line20, and process argon Ar1supplied through a process argon line18may be uniformly supplied to a silicon substrate through the gas injection unit2. For example, the gas injection unit2may be a showerhead. In some embodiments, the gas injection unit2may be connected to a radio frequency (RF) plasma generator to perform a plasma atomic layer deposition process. In other embodiments, the gas injection unit2may function as a plasma electrode.

Exhaust pumps may include the DCS exhaust pump3and the NH3exhaust pump4. Source gases used in a process are toxic, corrosive, and inflammable and are thus collected using a scrubber before being discharged to the outside air. In the embodiment, scrubbers are connected to rear ends of the exhaust pumps such that gases discharged through the pumps after a process may be filtered by the scrubbers and may then be discharged to the outside air in a purified state. That is, as illustrated inFIG. 6, the DCS scrubber11and the NH3scrubber12may respectively be connected to the DCS exhaust pump3and the NH3exhaust pump4. The DCS exhaust pump3and the DCS scrubber11may process a DCS source gas, and the NH3exhaust pump4and the NH3scrubber12may process NH3gas.

After passing through the reactor1, source/reaction gases may be discharged through the exhaust apparatus C. The exhaust apparatus C may include the main exhaust line5and the two sub-exhaust lines6and7. The main exhaust line5may branch into the two sub-exhaust lines6and7at a branching point13. The two sub-exhaust lines6and7are a DCS sub-exhaust line and an NH3sub-exhaust line, respectively.

The substrate processing apparatus may further include bypass lines. For example, the substrate processing apparatus being configured as an atomic layer deposition apparatus in the current embodiment may include the DCS bypass line8and the NH3bypass line9. In this case, DCS and NH3may be alternately supplied to the reactor1during an atomic layer deposition process. When DCS is supplied to the reactor1, NH3may be discharged to the NH3exhaust pump4through the NH3bypass line9, and when NH3is supplied to the reactor1, DCS may be discharged to the DCS exhaust pump3through the DCS bypass line8. That is, a continuous flow may be maintained while source/reaction gases are alternately supplied to the reactor1and the bypass lines8and9in a switching manner, and thus the inside pressure of gas lines and the reactor1may be constantly maintained, thereby ensuring process stability.

In the embodiment illustrated inFIG. 6, the substrate processing apparatus may further include the purge argon line10. The purge argon line10may be connected to the DCS sub-exhaust line6and the NH3sub-exhaust line7, and thus purge argon Ar2may be supplied to the DCS sub-exhaust line6and the NH3sub-exhaust line7through the purge argon line10.

For example, the purge argon line10may be connected to the DCS sub-exhaust line6at a front end15of a connection part14between the DCS bypass line8and the DCS sub-exhaust line6and may be connected to the NH3sub-exhaust line7at a front end17of a connection part16between the NH3bypass line9and the NH3sub-exhaust line7. In some embodiments, check valves may be respectively provided in the connection parts and ends14,15,16, and17to prevent gases from flowing backward from the sub-exhaust lines6and7to the bypass lines8and9or the purge argon line10.

FIG. 7is a schematic view illustrating an exhaust apparatus according to another embodiment. The exhaust apparatus of the current embodiment may be a modification of the exhaust apparatuses of the previous embodiments. Thus, the same description as that presented in the previous embodiments will not be presented here.

Referring toFIG. 7, a purge argon line10may branch into a DCS sub-exhaust line6and an NH3sub-exhaust line7. Devices allowing gas to flow only in one direction such as check valves v14and v12may be provided in connection parts15and17between the purge argon line10and the sub-exhaust lines6and7.

In some embodiments, as illustrated inFIG. 7, orifices v15and v13may be further provided between the purge argon line10and the sub-exhaust lines6and7. Each of the orifices v15and v13may be configured to maintain the flow rate of gas at a constant level. Therefore, owing to the orifices v15and v13, purge argon may always flow in the purge argon line10and the sub-exhaust lines6and7regardless of whether a DCS purge argon valve v9and an NH3purge argon valve v11are closed or opened.

For example, when the DCS purge argon valve v9is in a closed state, a certain amount of argon gas may be filled in a gas exhaust line between the check valve v14and the DCS purge argon valve v9so as to prevent a backflow of gas in the DCS sub-exhaust line6. The flow rate of purge argon at the orifices v15and v13may be set to be about 10% to about 15% of the flow rate of purge argon supplied to the purge argon line10.

FIGS. 8 to 13are schematic views illustrating an exhaust apparatus according to another embodiment. The exhaust apparatus of the current embodiment may be a modification of the exhaust apparatuses of the previous embodiments. Thus, the same description as that presented in the previous embodiments will not be presented here.

Referring toFIGS. 8 and 9, the exhaust apparatus may include an exhaust unit body21, a main exhaust line22, a DCS sub-exhaust line23, an NH3sub-exhaust line24, a DCS purge argon line25, an NH3purge argon line26, a DCS bypass line27, an NH3bypass line28, connection parts29and30, and cartridge heater holes33and34.

The main exhaust line22, the DCS sub-exhaust line23, the NH3sub-exhaust line24, the DCS bypass line27, and the NH3bypass line28of the exhaust apparatus illustrated inFIGS. 8 and 9may respectively correspond to the main exhaust line5, the DCS sub-exhaust line6, the NH3sub-exhaust line7, the DCS bypass line8, and the NH3bypass line9of the substrate processing apparatus illustrated inFIG. 6.

In addition, the DCS purge argon line25and the NH3purge argon line26of the exhaust apparatus illustrating inFIG. 8may branch off from the purge argon line10illustrated inFIG. 6. Therefore, argon gas may be supplied to the DCS purge argon line25and the NH3purge argon line26in an alternating manner by switching operations of the valves v9and v11(refer toFIG. 6). Similarly, DCS gas and NH3gas may be respectively supplied to the DCS bypass line27and the NH3bypass line28in an alternating manner by switching operations of valves v2and v5(refer toFIG. 6).

The connection parts29and30of the exhaust apparatus may be connected to gas analysis units (not shown). For example, the connection parts29and30may be connected to pressure gauges, and thus the pressures of the DCS sub-exhaust line23and the NH3sub-exhaust line24may be measured. In some embodiments, the connection parts29and30may be connected to exhaust gas component analyzers, and thus the compositions of exhaust gases may be analyzed to determine the amounts and compositions of remaining gases and gas supply conditions such as flow rates and supply times.

In addition, as described above, the DCS purge argon line25, the NH3purge argon line26, the DCS bypass line27, and the NH3bypass line28may include anti-backflow devices. The anti-backflow devices may be check valves and/or orifices allowing only unidirectional flows.

FIG. 9is a top view of the exhaust apparatus depicted inFIG. 8. The DCS bypass line27may be connected to the DCS sub-exhaust line23at a lateral side of the exhaust unit body21, and the NH3bypass line28may be connected to the NH3sub-exhaust line24at a rear side of the exhaust unit body21.

In some embodiments, cartridge heaters may be inserted into the cartridge heater holes33and34to heat the exhaust unit body21. If the exhaust unit body21is heated, reaction byproducts may not be deposited on internal exhaust lines or may not float in the exhaust unit body21.

FIGS. 10 and 11are cross-sectional views taken along lines A-A′ and B-B′ ofFIG. 8. Referring to the cross-sectional view of an exhaust unit inFIG. 10, a DCS exhaust path49and an NH3exhaust path50branching off from the main exhaust line22may be formed inside the exhaust unit body21, and the DCS exhaust path49and the NH3exhaust path50may be respectively connected to the DCS sub-exhaust line23and the NH3sub-exhaust line24.

The exhaust apparatus may further include a DCS gas supply ring31and an NH3gas supply ring32. The DCS gas supply ring31may be located between the DCS exhaust path49and the DCS sub-exhaust line23, and the NH3gas supply ring32may be located between the NH3exhaust path50and the NH3sub-exhaust line24.

The DCS gas supply ring31and the NH3gas supply ring32may be connected to the DCS bypass line27, the NH3bypass line28, the DCS purge argon line25, and the NH3purge argon line26. Therefore, Bypassed DCS and DCS purge argon may be discharged through the DCS gas supply ring31, the DCS sub-exhaust line23, the DCS exhaust pump3, and the DCS scrubber11, and bypassed NH3and NH3purge argon may be discharged through the NH3gas supply ring32, the NH3sub-exhaust line24, the NH3exhaust pump4, and the NH3scrubber12.

As illustrated inFIG. 10, the DCS bypass line27may be connected to the DCS gas supply ring31through a DCS bypass gas supply path48formed in a lateral side of the exhaust unit body21. Similarly, the NH3bypass line28may be connected to the NH3gas supply ring32through an NH3bypass gas supply path (not shown) formed in a rear side of the exhaust unit body21.

As illustrated inFIG. 11, the DCS purge argon line25and the NH3purge argon line26may respectively be connected to the DCS gas supply ring31and the NH3gas supply ring32through pipes penetrating an upper portion of the exhaust unit body21.

Purge gas (argon) may be discharged to the DCS exhaust pump3and the NH3exhaust pump4through the DCS purge argon line25, the NH3purge argon line26, purge gas supply paths formed in the exhaust unit body21, the DCS gas supply ring31, the NH3gas supply ring32, the DCS sub-exhaust line23, and the NH3sub-exhaust line24.

Similarly, bypassed DCS may be discharged to the DCS exhaust pump3through the DCS bypass line27, the DCS bypass gas supply path48, the DCS gas supply ring31, and the DCS sub-exhaust line23. In addition, bypassed NH3may be discharged to the NH3exhaust pump4through the NH3bypass line28, the NH3bypass gas supply path (not shown), the NH3gas supply ring32, and the NH3sub-exhaust line24.

FIG. 12is an exploded perspective view illustrating the exhaust apparatus depicted inFIG. 8, andFIG. 13is a cross-sectional view illustrating the exhaust unit body21. Referring toFIG. 12, the exhaust unit may include an upper plate35, the exhaust unit body21, the DCS gas supply ring31, and the NH3gas supply ring32, and a lower plate36.

The upper plate35is connected to the main exhaust line22, and as described above, the exhaust unit body21may include the DCS exhaust path49and the NH3exhaust path50that branch off from the main exhaust line22in the exhaust unit body21. A sealing measure37may be inserted between the exhaust unit body21and the upper plate35, and thus when the exhaust unit body21and the upper plate35are coupled to each other, sealing (isolation) may be provided. In the embodiment, the sealing measure may be an O-ring.

In addition, the purge gas supply paths may be formed in the exhaust unit body21. For example, a DCS purge argon supply path39and an NH3purge argon supply path40may be formed in the exhaust unit body21as the purge gas supply paths. The DCS purge argon supply path39may be connected between the DCS purge argon line25and the DCS gas supply ring31. The NH3purge argon supply path40may be connected between the NH3purge argon line26and the NH3gas supply ring32.

As illustrated inFIGS. 12 and 13, the DCS gas supply ring31and the NH3gas supply ring32are inserted into the exhaust unit body21. Each of the DCS gas supply ring31and the NH3gas supply ring32may include gas supply holes. Bypassed DCS gas and NH3gas, DCS purge argon, and NH3purge argon may be discharged through the gas supply holes. The DCS gas supply ring31and the NH3gas supply ring32will be further described hereinafter.

Referring toFIG. 13, exhaust paths may be continuously formed in the exhaust unit body21. In other words, paths may be bored through upper and lower portions of the exhaust unit body21so that exhaust paths connected to each other may be formed. Purge argon supplied to the exhaust unit body21through the DCS purge argon supply path39may be supplied to the DCS gas supply ring31through a gas supply hole46. In addition, bypassed NH3gas supplied to the exhaust unit body21through the NH3bypass line28and the NH3bypass gas supply path (not shown) may be supplied to the NH3gas supply ring32through a gas supply hole47. The positions, sizes, and shapes of holes illustrated in the drawings are examples.

An upper portion of the lower plate36may be connected to the DCS gas supply ring31and the NH3gas supply ring32, and a lower portion of the lower plate36may be connected to the DCS sub-exhaust line23and the NH3sub-exhaust line24. A sealing measure38may be inserted between the lower plate36and the gas supply rings31and32. Thus, when the lower plate36is coupled to the gas supply rings31and32, outside air may not permeate. In the embodiment, the sealing measure may be an O-ring.

FIG. 14is a schematic view illustrating a gas supply ring31or32according to an embodiment.FIGS. 15 to 17are cross-sectional views illustrating modifications of the gas supply ring illustrated inFIG. 14. The gas supply ring of the current embodiment may be applied to the exhaust apparatuses of the previous embodiments.

Referring toFIG. 14, the gas supply ring31or32may be inserted into the exhaust unit body21and may be connected to the DCS sub-exhaust line23or the NH3sub-exhaust line24. The gas supply ring31or32may include upper holes41, lower holes42, and sealing measure insertion portions43and44.

The upper holes41provide paths through which DCS and NH3purge argon are discharged, and the lower holes42provide paths through which bypassed DCS and NH3are discharged. That is, the upper holes41may be arranged between the lower holes42and the main exhaust line22including a first region. A gas curtain may be formed in an exhaust path by supplying purge argon to the upper holes41arranged as described above. In addition, the upper holes41through which purge argon is discharged are located between the lower holes42of the gas supply ring31or32and the first region through which DCS and NH3are respectively discharged (or NH3and DCS are respectively discharged), thereby preventing DCS and NH3from meeting each other and the formation of reaction byproducts in an exhaust unit.

O-rings may be inserted in the sealing measure insertion portions43and44. Thus, gas discharged through the upper holes41(or the lower holes42) may not leak to the lower holes42(or the upper holes41). In addition, gas leakage between the gas supply ring31or32and the exhaust unit body21may be prevented. That is, owing to the sealing measures (the O-rings), gases passing through the upper holes41and the lower holes42may be not mixed with each other and isolated from the outside.

Referring toFIG. 14, an upper portion45of the gas supply ring31or32and an exhaust path formed inside the exhaust unit body21may be brought into tight contact with each other and thus be sealed via face sealing. In other embodiments, however, a sealing measure such as an O-ring may be provided on the upper portion45of the gas supply ring31or32.

As described above, a purge argon gas curtain may be uniformly formed in an exhaust line owing to the upper holes41and the lower holes42, and thus bypassed DCS gas or NH3gas may be uniformly discharged.

In addition, as illustrated inFIGS. 15 to 17, a plurality of holes may be symmetrically arranged along a lateral side of the gas supply ring31or32. For example, four holes may be symmetrically arranged as illustrated inFIG. 15, eight holes may be symmetrically arranged as illustrated inFIG. 16, or sixteen holes may be symmetrically arranged as illustrated inFIG. 17.

The diameter and number of such symmetric holes may be determined to minimize adiabatic expansion of DCS gas and NH3gas (and a resulting increase in gas flow velocity and a temperature decrease) during a bypass process. Both DCS and NH3are gases that may be liquefied, and thus if the temperature of DCS or NH3is rapidly decreased, solid byproducts may be formed on the exhaust apparatus (for example, on an exhaust line, a pump, or a scrubber). Therefore, the diameter and number of such symmetric holes may be adjusted to previously prevent clogging of the exhaust apparatus.

In other words, according to the embodiment, as illustrated inFIGS. 15 to 17, the amount of source gas or reaction gas passing through a unit hole (a single hole) per unit time may be reduced by forming a plurality of holes. Therefore, the temperature of bypassed source gas (DCS) or reaction gas (NH3) passing through the lower holes42may not be decreased by adiabatic expansion.

Alternatively, the amount of source gas or reaction gas passing through a unit hole (a single hole) per unit time may be reduced by forming small holes, so as to prevent a decrease in the temperature of the source gas or reaction gas (NH3) caused by adiabatic expansion. The diameter of the lower holes42may be within the range of about 2 mm to about 3 mm. For example, the diameter of the lower holes42may be 2 mm.

FIG. 18is a schematic view illustrating a thin film fabricating method according to an embodiment. The thin film fabricating method of the current embodiment may be performed using the exhaust apparatuses or the substrate processing apparatuses of the previous embodiments. Thus, the same description as that presented in the previous embodiments will not be presented here.

Referring toFIG. 18, the thin film forming method may include a first step t1 in which a source gas is supplied, a second step t2 in which the source gas is purged, a third step t3 in which a reaction gas is supplied, and a fourth step t4 in which plasma is supplied. The source gas, the reaction gas, and the plasma may be sequentially supplied, and while the source gas, the reaction gas, and the plasma are supplied, a first purge gas and a second purge gas may be continuously supplied to a reaction space.

In addition, a fifth step t5 may be performed to purge remaining gases after the first to fourth steps t1 to t4. In addition, a cycle of the first to fourth steps t1 to t4 (or the first to fifth steps t1 to t5) may be repeated several times.

During the second step t2, the source gas and the first purge gas from a reactor may be discharged through a first path (for example, a first sub-exhaust line) of an exhaust unit. At the same time, the second purge gas may be supplied to a second path (for example, a second sub-exhaust line) of the exhaust unit. The second purge gas may form a gas curtain in the second path of the exhaust unit.

Meanwhile, when one of the source gas and the reaction gas is supplied to the reactor, the other gas may be bypassed to the exhaust unit. While the source gas is supplied in the first step t1, the reaction gas may flow to the exhaust unit through a bypass line. This exhaust flow through the bypass line may maintain continuous flows of gases, and thus the inside pressures of gas lines and the reactor may be constantly maintained.

A path through which bypassed gas is discharged is different from a path through which gas discharged from the reactor is discharged. For example, during the third step t3, the reaction gas and the first purge gas may be supplied to the reactor, and during the fourth step t4, the reaction gas and the first purge gas may be discharged from the reactor. In this case, the reaction gas and the first purge gas may be discharged through the second path (for example, the second sub-exhaust line), and bypassed gas (the source gas) may be discharged through the first path (for example, the first sub-exhaust line).

FIG. 19is a schematic view illustrating a thin film forming method according to another embodiment. The thin film forming method of the current embodiment may be a modification of the thin film forming method of the previous embodiment. Thus, the same description as that presented in the previous embodiment will not be presented here.

The thin film forming method may be a method of depositing silicon nitride through an atomic layer deposition process. That is, DCS gas and NH3gas may be sequentially supplied as a source gas and a reaction gas, and plasma may be supplied in synchronization with the supply of NH3gas. NH3gas may be activated by the plasma and react with DCS molecules adsorbed on a substrate, and thus a SixNy layer may be formed on the substrate. These steps may be repeated to increase the thickness of the SixNy layer to a target thickness.

Referring toFIG. 19, a basic cycle including DCS supply (first step step t1), purge (second step t2), NH3pre-flow (third step t3), NH3plasma (fourth step t4), and purge (fifth step t5) may be repeated several times until a thin film having a desired thickness is deposited. In third step t3, NH3may be supplied before plasma is applied. Owing to this NH3pre-flow, NH3may be uniformly distributed in a reaction space, and in the next NH3excitation operation (fourth step t4), NH3plasma may be uniformly distributed in the reaction space.

During steps t1 to t5, process argon Ar1may be continuously supplied to the reaction space. The process argon Ar1may uniformize the inside pressure of the reaction space and may have a function of purging DCS or NH3gas from the reaction space during steps t2 or t5.

In addition, the flow rate of process argon Ar1may be adjusted in each step by taking into consideration a total gas flow rate including the flow rate of DCS and the flow rate of NH3. That is, the sum of the flow rate of process argon Ar1and the flow rate of DCS supplied to the reaction space in step t1 may be set to be equal to the flow rate of process argon Ar1supplied to the reaction space in step t2. In other words, the flow rate of process argon Ar1in step t1 may be lower than the flow rate of process argon Ar1in step t2.

Similarly, since NH3and process argon Ar1are supplied to the reaction space in steps t3 and t4, the flow rate of process argon Ar1supplied to the reaction space during steps t3 and t4 may be lower than the flow rate of process argon Ar1supplied to the reaction space in step t2 or t5. In this manner, the total flow rate of gases supplied to the reaction space may be constantly maintained throughout steps t1 to t5. Thus, the inside pressure of the reaction space may be constantly maintained during steps t1 to t5, and process stability may be improved.

Referring toFIG. 19, purge argon Ar2may be continuously supplied during steps t1 to t5. However, unlike the process argon Ar1, the purge argon Ar2may not be supplied to the reaction space but may be supplied to the DCS sub-exhaust line6or the NH3sub-exhaust line7through the purge argon line10. In the current embodiment, the purge argon Ar2may flow to the NH3sub-exhaust line7during steps t1 to t2 and to the DCS sub-exhaust line6during steps t3 to t5.

Gas flows during steps t1 to t5 will now be specifically described with reference toFIG. 19.

1) Step 1 (t1): DCS is supplied (DCS feeding step). In step 1 (t1), DCS source gas is supplied to a reactor and adsorbed in a substrate loaded in the reactor.

Referring toFIG. 6, a DCS supply valve V1of the DCS line19is opened to supply DCS to the reactor1. At the same time, process argon Ar1is supplied to the reactor1through the process argon line18, a second process argon supply valve v6, and the NH3line20. At this time, an exhaust valve v7of the main exhaust line5is in an opened state, and DCS and process argon Ar1remaining in the reactor1is directed to the DCS sub-exhaust line6and the DCS exhaust pump3and is discharged to the outside after being purified by the DCS scrubber11. At this time, an NH3supply valve v4is in a closed state, and thus NH3is discharged to the outside through a first NH3bypass valve v5, the NH3bypass line9, a second NH3bypass valve v10, the NH3exhaust pump4, and the NH3scrubber12.

Meanwhile, purge argon Ar2may be supplied to the NH3sub-exhaust line7through the purge argon line10and an NH3purge argon valve v11and may then be discharged to the outside through the NH3exhaust pump4and the NH3scrubber12. The purge argon Ar2supplied to the NH3sub-exhaust line7may form a gas curtain between the NH3sub-exhaust line7and the DCS sub-exhaust line6. Therefore, DCS source gas discharged to the DCS sub-exhaust line6may not flow back to the NH3sub-exhaust line7, and thus solid byproducts may not be formed on the NH3sub-exhaust line7by preventing a reaction between the DCS source gas and NH3.

In this step, a first DCS bypass valve v2, a second DCS bypass valve v8, and a DCS purge argon valve v9are in a closed state. In this case, an anti-backflow device such as a check valve (not shown) may be placed in the connection part16between the NH3bypass line9and the NH3sub-exhaust line7. Therefore, purge argon Ar2and NH3discharged to the NH3sub-exhaust line7may not flow back to the NH3bypass line9. In some embodiments, during step 1, the first NH3bypass valve v5may be closed to prevent NH3from flowing to the NH3bypass line9. In this case, the consumption of NH3may be reduced.

2) Step 2 (t2): DCS is purged (DCS purge step). In step 2, the supply of DCS is stopped, and DCS source gas having not undergone a reaction and remaining in the reactor1and on a substrate is purged from the reactor1. In this step, the DCS supply valve v1and the second process argon supply valve v6are closed, and a first process argon supply valve v3is opened, so as to supply process argon Ar1to the reactor1through the DCS line19. Therefore, DCS gas remaining in the DCS line19, the gas injection unit2, and the reactor1may be purged to the main exhaust line5.

During step 2, DCS may be discharged to the outside through the first DCS bypass valve v2, the DCS bypass line8, the second DCS bypass valve v8, the DCS exhaust pump3, and the DCS scrubber11.

An anti-backflow device such as a check valve (not shown) may be placed in the connection part14between the DCS bypass line8and the DCS sub-exhaust line6so as to prevent gas flowing from the reactor1to the DCS sub-exhaust line6and DCS source gas discharged from the DCS bypass line8from flowing back along the DCS bypass line8. In some embodiments, during step 2, however, the first DCS bypass valve v2may be closed to prevent DCS gas from flowing to the DCS bypass line8. In this case, the consumption of DCS source gas may be reduced.

During step 2, like in step 1, NH3may be discharged to the outside through the NH3bypass line9, the NH3sub-exhaust line7, the NH3exhaust pump4, and the NH3scrubber12. In addition, purge argon Ar2may flow to the NH3sub-exhaust line7through the purge argon line10and the NH3purge argon valve v11, and thus a gas curtain may be formed between the DCS sub-exhaust line6and the NH3sub-exhaust line7.

3) Step 3 (t3): NH3previously flows (NH3pre-flow operation). In this step, NH3is supplied to the reactor1as a reaction gas. As NH3is supplied to the reactor1, the distribution of NH3in the reactor1becomes uniform, and when the NH3is activated by plasma in the next step 4, the concentration of NH3radicals in a reactor1may become uniform.

Referring toFIG. 6, the NH3supply valve v4of the NH3line20is opened to supply NH3to the reactor1. At the same time, process argon Ar1is supplied to the reactor1through the process argon line18, the first process argon supply valve v3, and the DCS line19. At this time, the exhaust valve v7of the main exhaust line5may be in an opened state, and NH3and process argon Ar1remaining in the reactor1may be discharged to the outside through the NH3sub-exhaust line7, the NH3exhaust pump4, and the NH3scrubber12after being purified. During step 3, the first NH3bypass valve v5, the second NH3bypass valve v10, and the NH3purge argon valve v11are in a closed state.

The DCS supply valve v1is in a closed state, and thus DCS gas may be discharged to the outside through the first DCS bypass valve v2, the DCS bypass line8, the second DCS bypass valve v8, the DCS sub-exhaust line6, the DCS exhaust pump3, and the DCS scrubber11.

Meanwhile, purge argon Ar2may be supplied to the DCS sub-exhaust line6through the purge argon line10and the DCS purge argon valve v9and may then be discharged to the outside through the DCS exhaust pump3and the DCS scrubber11. The purge argon Ar2supplied to the DCS sub-exhaust line6may form a gas curtain between the DCS sub-exhaust line6and the NH3sub-exhaust line7. Therefore, discharged NH3reaction gas may not flow back to the DCS sub-exhaust line6, and thus solid byproducts may not be formed on the DCS sub-exhaust line6by preventing a reaction between the NH3reaction gas and DCS gas.

An anti-backflow device such as a check valve (not shown) may be placed in the connection part14between the DCS bypass line10and the DCS sub-exhaust line6. Therefore, DCS source gas and purge argon Ar2flowing in the DCS sub-exhaust line6may be prevented from flowing back to the DCS bypass line8. In step 3, however, the first DCS bypass valve v2may be closed to prevent DCS gas from flowing to the DCS bypass line8. In this case, the consumption of DCS source gas may be reduced.

4) Step 4 (t4): NH3is activated by plasma (plasma excitation step). In this step, NH3supplied to the reactor1in step 3 is activated by plasma. In this step, NH3is continuously supplied, and each valve and each gas are operated and directed in the same manner as in step 3. As illustrated inFIG. 6, plasma may be generated above a substrate placed inside the reactor1by an in-situ plasma method. Alternatively, plasma may be generated outside the reactor1and may be supplied to a reaction space of the reactor1by a remote plasma method. NH3may be activated using an ultraviolet (UV) generator instead of using an RF generator.

5) Step5 5 (t5): NH3is purged (NH3purge operation). In step 5 (t5), the supply of NH3is stopped, and NH3reaction gas having not undergone a reaction and remaining in the reactor1and on a substrate is discharged from the reactor1. In step 5, the NH3supply valve v4and the first process argon supply valve v3are closed, and the second process argon supply valve v6is opened, so as to supply process argon Ar1to the reactor1through the NH3line20. Therefore, NH3gas remaining in the NH3line20, the gas injection unit2, and the reactor1is purged to the main exhaust line5. At this time, NH3is discharged to the outside through the first NH3bypass valve v5, the NH3bypass line9, the second NH3bypass valve v10, the NH3sub-exhaust line7, the NH3exhaust pump4, and the NH3scrubber12.

An anti-backflow device such as a check valve (not shown) may be placed in the connection part16between the NH3bypass line9and the NH3sub-exhaust line7so as to prevent purge argon Ar2and NH3discharged to the NH3sub-exhaust line7from flowing back to the NH3bypass line9. However, the first NH3bypass valve v5may be closed to prevent NH3from flowing to the NH3bypass line9. In this case, the consumption of NH3may be reduced.

During step 5, like in steps 3 and 4, DCS gas may be discharged to the outside through the DCS bypass line8, the DCS sub-exhaust line6, the DCS exhaust pump3, and the DCS scrubber11. Purge argon Ar2may flow to the DCS sub-exhaust line6through the purge argon line10and the DCS purge argon valve v9, and thus a gas curtain may be formed between the DCS sub-exhaust line6and the NH3sub-exhaust line7. In this step, however, the first DCS bypass valve v2may be closed to prevent DCS gas from flowing to the DCS bypass line8. In this case, the consumption of DCS source gas may be reduced.

The descriptions of the previous embodiments have been presented based on an atomic layer deposition process or a plasma atomic layer deposition process. However, the embodiments are for illustrative purposes only. The inventive concept is to form a gas curtain in a second region to prevent a first gas from being discharged through the second region when the first gas is supplied and discharged through a first region and a gas curtain in the first region to prevent a second gas from being discharged through the first region when the second gas is supplied and discharged through the second region, and the inventive concept may be applied to not only deposition processes but also chemical vapor deposition (CVD) processes, cleaning processes, and other processes in which fluids are required to be separately discharged.