Apparatus and method of treating a substrate

Provided are an apparatus and a method of treating a substrate using process gas. The apparatus may include a chamber configured to provide a treatment space, in which a process of treating a substrate is performed, a detection unit configured to detect an amount of reaction by-products attached on an inner surface of the chamber. The detection unit may include a window member provided on the inner surface of the chamber, and a light source member configured to emit and receive light through the window member.

CROSS-REFERENCE TO RELATED APPLICATIONS

This U.S. non-provisional patent application claims priority under 35 U.S.C. § 119 to Korean Patent Application No. 10-2014-0011181, filed on Jan. 29, 2014, in the Korean Intellectual Property Office, the entire contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

Exemplary embodiments of the inventive concept relate to an apparatus and a method of treating a substrate, and in particular, to an apparatus and a method of treating a substrate using process gas.

A semiconductor device is fabricated through several processes, such as photolithography, etching, thin-film deposition, ion implantation, and cleaning processes. Here, a substrate treating apparatus using plasma may be used to perform the etching, thin-film deposition, and cleaning processes.

Normally, a plasma treatment process may include steps of supplying process gas into a chamber and of treating a substrate using plasma generated from the process gas. However, in such a plasma treatment process, a fraction of the plasma may be attached on an inner surface of the chamber, thereby serving as a particle source. Accordingly, a cleaning process may be performed to preserve a desired clean level of an internal space of the chamber, before and/or after the plasma process.

The cleaning process may include steps of supplying cleaning gas into the chamber and of measuring a state of plasma generated in the chamber.FIGS. 1 and 2are sectional views illustrating a substrate treating apparatus according to a conventional technology. Referring toFIGS. 1 and 2, a transparent window2may be provided through a sidewall of a chamber, and a sensor3may be provided near the transparent window2to measure a plasma state in the chamber state and monitor a corresponding cleaning state. Alternatively, a sensor4may be used to examine the composition of process by-products, which may be produced in the chamber, when the process by-products are exhausted. The cleaning state of the chamber may be determined based on the examined composition.

However, in the case where the cleaning state of the chamber is examined using the afore-described methods, it is difficult to properly monitor the actual cleaning state of the inner surface of the chamber.

RELEVANT PUBLISHED DOCUMENTS

SUMMARY

Example embodiments of the inventive concept provide an apparatus and a method capable of examining a state of an inner surface of a chamber with higher accuracy.

Other example embodiments of the inventive concept provide an apparatus and a method capable of cleaning an inner surface of a chamber and preserving a state of the inner surface of the chamber to a pre-determined condition.

According to example embodiments of the inventive concept, a substrate treating apparatus may include a chamber configured to provide a treatment space, in which a process of treating a substrate is performed, a detection unit configured to detect an amount of reaction by-products attached on an inner surface of the chamber. The detection unit may include a window member provided on the inner surface of the chamber, and a light source member configured to emit and receive light through the window member.

In example embodiments, the window member may include a coating layer coated on an inner side surface thereof and formed of the same material as that of an inner surface of the chamber. An inner side surface of the coating layer may be substantially coplanar with the inner surface of the chamber. The window member may include a first view port including a first transparent window provided on a sidewall of the chamber and a second view port including a second transparent window provided on the sidewall of the chamber to face the first view port. The light source member may include a light-emitting device provided outside the first transparent window and configured to emit light, and a light-receiving device provided outside the second transparent window and configured to receive light emitted from the light-emitting device.

In other embodiments, the window member may include a transparent window provided on a sidewall of the chamber. The light source member may include a light-emitting device provided outside the transparent window and configured to emit light, and a light-receiving device provided outside the transparent window and configured to receive light reflected from the transparent window.

In example embodiments, the substrate treating apparatus may further include a gas-supplying unit including a gas-supplying line, which is configured to supply cleaning gas to the treatment space, and a valve, which is configured to open and close the gas-supplying line, and a plasma source configured to generate plasma from the cleaning gas to be supplied into the treatment space. The detection unit may include a controller controlling the light source member and the gas-supplying unit, and the controller may be configured to control a cleaning process, which is performed to clean the treatment space before and/or after the process of treating the substrate, until detection information obtained by the light-receiving device may be coincident with a pre-determined condition. Here, the pre-determined condition may include information on an inner surface state of the chamber.

According to example embodiments of the inventive concept, a method of treating a substrate may include emitting and receiving light through a window member provided on an inner surface of a chamber, in which a plasma treatment process may be performed, to detect an amount of reaction by-products attached on the inner surface.

In example embodiments, the window member may include a coating layer coated on an inner side surface thereof and formed of the same material as that of the inner surface. An inner side surface of the coating layer may be substantially coplanar with the inner surface. The method may further include comparing the detection information on an amount of reaction by-products with a pre-determined condition, supplying cleaning gas into the chamber to perform a cleaning treatment on an internal space of the chamber, if the detection information is not coincident with the pre-determined condition, and terminating the supplying of the cleaning gas, if the detection information is coincident with the pre-determined condition.

According to example embodiments of the inventive concept, a method of treating a substrate may include a cleaning treatment step of cleaning an internal space of a chamber, in which a treatment process may be performed, a substrate treatment step of supplying process gas into the chamber to treat a substrate. The cleaning treatment step may include a cleaning gas supplying step of supplying cleaning gas into the chamber, a detecting step of emitting and receiving light through a window member provided on an inner surface of the chamber and detecting an amount of reaction by-products attached on the inner surface.

In example embodiments, the cleaning treatment step may further include comparing information on an amount of reaction by-products with a pre-determined condition, supplying cleaning gas into the chamber to clean an internal space of the chamber, if the detection information is not coincident with the pre-determined condition, and terminating the supplying of the cleaning gas, if the detection information is coincident with the pre-determined condition. The cleaning treatment step and the substrate treatment step may be alternatingly performed.

DETAILED DESCRIPTION

Hereinafter, an apparatus and a method of treating a substrate using process gas will be described. However, example embodiments of the inventive concept may not be limited thereto. For example, the inventive concept can be applied to any process and apparatus using plasma.

Hereinafter, exemplary embodiments of the inventive concept will be described with reference toFIGS. 3 through 7.

FIG. 3is a sectional view illustrating a substrate treating apparatus, according to exemplary embodiments of the inventive concept. Referring toFIG. 3, a substrate treating apparatus10may include a chamber100, a substrate-supporting unit200, a gas-supplying unit300, a plasma source400, a baffle500, and a detection unit600.

The chamber100may be configured to provide a treatment space, in which a substrate W is treated. The chamber100may be provided in the form of a cylinder. The chamber100may be formed of or include a metal-based material. For example, the chamber100may be formed of an aluminum-based material. An exhaust hole150may be formed in a bottom surface of the chamber100. The exhaust hole150may be connected to a pressure-reducing member160through an exhausting line. The pressure-reducing member160may be configured to provide a vacuum pressure to the exhaust hole150through the exhausting line. The vacuum pressure may allow process by-products and/or plasma remaining in the chamber100to be exhausted to the outside of the chamber100.

The substrate-supporting unit200may be disposed in the treatment space to support the substrate W loaded therein. The substrate-supporting unit200may support the substrate W using an electrostatic force. In other words, the substrate-supporting unit200may serve as an electrostatic chuck200. In certain embodiments, the substrate-supporting unit200may be configured to support the substrate W using other means (e.g., with a mechanical clamp).

The electrostatic chuck200may include a dielectric plate210, a focus ring250, and a base230. The substrate W may be directly loaded on a top surface of the dielectric plate210. The dielectric plate210may be provided in the form of a circular disk. The dielectric plate210may have a radius smaller than that of the substrate W. A lower electrode212may be equipped in the dielectric plate210. The lower electrode212may be connected to a power supply (not shown) and may be supplied with an electric power provided from the power supply (not shown). The lower electrode212may produce an electrostatic force from the supplied electric power (not shown), and the electrostatic force may be used to electrically attach the substrate W onto the dielectric plate210. In example embodiments, the lower electrode212may be provided in the form of a monopolar electrode. A heater214may be provided in the dielectric plate210to heat the substrate W. The heater214may be disposed below the lower electrode212. The heater214may be provided in the form of a spiral coil. The dielectric plate210may be formed of or include, for example, a ceramics-based material.

The base230may support the dielectric plate210. The base230may be provided below the dielectric plate210and may be fastened and coupled to the dielectric plate210. The base230may be provided in such a way that a top surface thereof is higher at a central region than at an edge region. For example, the base230may be provided to have a staircase structure. Further, the base230may be configured in such a way that the top surface at the central region has substantially the same area as that of a bottom surface of the dielectric plate210. A coolant flow passage232may be provided in the base230to circulate coolant therethrough. In the base230, the coolant flow passage232may be provided to have a spiral shape. The base230may be coupled to a radio frequency (RF) power (not shown) located at the outside of the chamber100. The RF power may apply an electric power to the base230. The electric power applied to the base230may be used to guide plasma produced in the chamber100toward the base230. The base230may be formed of or include a metal-based material.

The focus ring250may focus or concentrate plasma on the substrate W. The focus ring250may include an inner ring252and an outer ring254. The inner ring252may be provided in the form of a circular ring enclosing the dielectric plate210. The inner ring252may be provided on the edge region of the base230. The inner ring252may have a top surface substantially coplanar with that of the dielectric plate210. The top surface of the inner ring252may include an inner side portion supporting an edge region of the bottom surface of the substrate W. For example, the inner ring252may be formed of or include a conductive material. The outer ring254may be provided in the form of a circular ring enclosing the inner ring252. The outer ring254may be provided on the edge region of the base230and adjacent to the inner ring252. The outer ring254may be provided in such a way that a top surface thereof is located at a higher level than that of the inner ring252. The outer ring254may be formed of or include an insulating material.

The gas-supplying unit300may be configured to supply process gas and cleaning gas onto the substrate W supported by the substrate-supporting unit200. The gas-supplying unit300may include a process gas storage350, a gas-supplying line330, and a gas in-flow port310. The process gas storage350may include a first gas storage351and a second gas storage352. First gas may be contained or stored in the first gas storage351, and second gas may be contained or stored in the second gas storage352. The first and second gases may be of different kinds. The gas-supplying line330may connect the first gas storage351and the second gas storage352to the gas in-flow port310. The first and second gases, which are contained in the first and second gas storages351and352, respectively, may be supplied to the gas in-flow port310through the gas-supplying line330. A first valve351aand a second valve352amay be equipped on the gas-supplying line330. The first valve351amay be configured to open and close a pathway for supplying the first gas, and the second valve352amay be configured to open and close a pathway for supplying the second gas. In example embodiments, the first gas may be used as a substrate treating gas. For example, the first gas may be used as an etching gas. The second gas may be used as a cleaning gas.

The plasma source400may be configured to cause the process gas in the chamber100to be excited into a plasma state. In example embodiments, an inductively-coupled plasma (ICP) source may be used as the plasma source400. The plasma source400may include an antenna410and an external power430. The antenna410may be disposed outside or on the chamber100. The antenna410may be provided to have a spiral structure with a plurality of windings and may be coupled to the external power430. The antenna410may be supplied with an electric power provided from the external power430. In the case where the electric power is applied to the antenna410, a discharge space may be formed in the treatment space of the chamber100. The process gas positioned in the discharge space may be excited into a plasma state.

The baffle500may allow the plasma to be uniformly generated in the treatment space.FIG. 4is a plan view illustrating the baffle ofFIG. 3. The baffle500may be provided in the treatment space and between an inner sidewall of the chamber100and the supporting unit400. The baffle500may be provided in the form of a circular ring. The baffle500may have a plurality of through holes502. The through holes502may be formed to penetrate the baffle500in a vertical direction. The through holes502may be provided spaced apart from each other in a circumference direction of the baffle500. Each of the through holes502may be shaped like a slit. The through hole502may has a shape elongated in a radial direction of the baffle500.

The detection unit600may be configured to detect an amount of reaction by-products to be attached on the inner surface of the chamber100. For example, the detection unit600may measure a physical state of the inner surface of the chamber100using light.FIG. 5is a sectional view illustrating the detection unit600ofFIG. 3. Referring toFIG. 5, the detection unit600may include a window member610, a light source member630, and a controller650. The window member610may include a first view port610aand a second view port610b. In example embodiments, the first view port610aand the second view port610bmay be provided to have the same shape. The first view port610amay be provided on a sidewall of the chamber100. The first view port610amay be configured to be equipped to or be removed from a first detection hole, which is formed on a sidewall of the chamber100. The first view port610amay be provided at a level higher than that of the electrostatic chuck. The first view port610amay include a first frame612and a first transparent window614. The first frame612may be provided in the form of a ring enclosing a circumference of the first transparent window614. The first frame612and the first transparent window614may be coupled to each other in a fastened manner. An inner side surface of the first frame612and the first transparent window614may be coated with a coating layer616. In example embodiments, the coating layer616may be formed of or include the same material as the inner surface of the chamber100. As an example, an inner side surface of the coating layer616may be positioned on the same plane as the inner surface of the chamber100, and for this, the coating layer616may be coated on, for example, the first transparent window614. The coating of the coating layer616may be performed by one of various coating apparatuses (e.g., an atomic layer deposition (ALD) system, a sputter, a spray, and an evaporator).

The second view port610bmay be provided on a sidewall of the chamber100positioned opposite to the first view port610a. The second view port610bmay include a second frame and a second transparent window. The second frame and the second transparent window may be configured to have the same configuration as the first frame612and the first transparent window614, respectively, and thus, a detail description thereof will be omitted.

The light source member630may be configured to emit and receive light through the window member610. The light source member630may include a light-emitting device632and a light-receiving device634. The light-emitting device632and the light-receiving device634may be arranged, outside the first view port610aand the second view port610b, respectively. The light-emitting device632may be provided adjacent to the first view port610a, and the light-receiving device634may be provided adjacent to the second view port610b. The light-emitting device632and the light-receiving device634may be provided to face each other. In the case where light is emitted from the light-emitting device632, the light may pass through the first view port610aand the second view port610band then may be incident into the light-receiving device634.

The controller650may control the light-receiving device634and the second valve352a. The controller650may control the second valve352a, based on detection information obtained by the light-receiving device634. The second valve352amay be controlled by the controller650to obtain the detection information coincident with a pre-determined condition. As an example, in the case where the detection information is not coincident with the pre-determined condition, the controller650may open the second valve352a, whereas in the case where the detection information is coincident with the pre-determined condition, the controller650may close the second valve352a.

Next, a method of cleaning the treatment space of the chamber100using the substrate treating apparatus will be exemplarily described.FIG. 6is a block diagram exemplarily illustrating a process of treating a substrate using the substrate treating apparatus ofFIG. 3. Referring toFIG. 6, the light-emitting device632may be configured to emit light toward the first view port610a, and the light-receiving device634may be configured to receive the light through the second view port610b. The second valve352amay be opened to supply cleaning gas into the treatment space. The cleaning gas may contain a material capable of cleaning an inner surface of the chamber100. If the inner surface of the chamber100is treated with the cleaning gas, an amount of light to be incident into the light-receiving device634may be changed. The controller650may determine whether the detection information is coincident with the pre-determined condition, based on the detection information obtained by the light-receiving device634. If the detection information is coincident with the pre-determined condition, the controller650may close the second valve352aand the cleaning process may be terminated.

As described above, the detection unit600may include a plurality of view ports610, but example embodiments of the inventive concepts may not be limited thereto. For example, as shown inFIG. 7, the view port610may be singly provided. The view port may be provided on a sidewall of the chamber100, and the light-emitting device632and the light-receiving device634may be provided adjacent to the view port610. The light-emitting device632may be configured to emit light through the view port610, and the, a fraction of the emitted light may be reflected by reaction by-products deposited on a transparent window. The light-receiving device634may be configured to receive the reflected light, and the controller650may compare detection information obtained by the light-receiving device634with a pre-determined condition.

According to example embodiments of the inventive concept, a window member may be equipped on an inner surface of a chamber, and light may be emitted and received through the window member to measure an internal state of the chamber. Accordingly, it is possible to measure a state of the inner surface of the chamber with higher accuracy.

According to example embodiments of the inventive concept, a coating layer may be coated on an inner side surface of the window member. Here, the coating layer may be formed of the same material as that of the inner surface of the chamber. Accordingly, the inner side surface of the window member can be preserved to be the same state as that of the inner surface of the chamber, and this makes it possible to measure the state of the inner surface of the chamber with higher accuracy.

According to example embodiments of the inventive concept, an amount of reaction by-products attached on the inner surface of the chamber may be determined, based on information on light emitted and received through the window member, and a cleaning process may be performed in such a way that the information on light emitted and received is coincident with a pre-determined condition. Accordingly, the inner surface of the chamber can be maintained to the same state, even when the cleaning process is repeatedly performed.