Substrate Processing Apparatus and Substrate Processing Method

Abstract

To provide a substrate processing apparatus capable of reducing a process time when an ALD window uses different precursors without overlapping and having the uniform thickness scattering of a thin film, and a substrate processing method using the same.SOLUTION: A substrate processing apparatus includes: a process chamber having a reaction space formed in the inside; a substrate support part including a susceptor plate, a plurality of vacuum holes formed on the upper surface of the susceptor plate and a vacuum line connected to a pump included in the outside through the plurality of vacuum holes and placed in the reaction space so as to support a plurality of substrates; a gas injection part facing the substrate support part so as to inject process gas into the reaction space and including a plurality of gas injection units radially arranged; and a control part for controlling the fixing force (chucking force) of the substrate according to the kind of gas supplied through the gas injection part.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to an apparatus and a method for processing a substrate, and more particularly, to a substrate processing apparatus and a substrate processing method using the same.

Background Art

[0002] Generally, in order to manufacture semiconductor elements, display elements, or solar cells, various processes are performed using a substrate processing apparatus including a process chamber in a vacuum atmosphere. For example, a substrate may be loaded into the process chamber, and processes such as depositing a thin film on the substrate or etching the thin film may be performed. The substrate is supported by a substrate support assembly installed in the process chamber, and process gas can be injected onto the substrate through a gas injection unit installed to face the substrate support assembly.

[0003] In such a substrate processing apparatus, when using different precursors whose ALD windows do not overlap, a thin film is deposited using one process temperature. When using a precursor that does not satisfy the ALD window under the condition of one process temperature, a part is deposited in the CVD (Chemical Vapor Deposition) region, and the thickness dispersion of the thin film with respect to the precursor is poor. In order to make the thickness dispersion of the thin film constant, a technique of changing the heater setting temperature during the progress of the ALD thin film deposition process is applied.

[0004] However, when changing the heater setting temperature during the process, due to the heat capacity depending on the size of the chamber, it takes about one hour or more to stabilize after changing the heater setting temperature, so there is a problem that the process time becomes very long when the process satisfying the ALD window progresses.

Summary of the Invention

Problems to be Solved by the Invention

[0005] The present invention is for solving various problems including the above-mentioned problems. When using different precursors where the ALD windows do not overlap, the process time can be shortened, and an object is to provide a substrate processing apparatus in which the thickness distribution of a thin film is uniform and a substrate processing method using the same. However, such problems are exemplary and do not limit the scope of the present invention thereby.

Means for Solving the Problems

[0006] A substrate processing apparatus according to an embodiment of the present invention for solving the above problems includes: a process chamber in which a reaction space is formed; a susceptor plate, a plurality of vacuum holes formed on the upper surface of the susceptor plate, and a vacuum line connected to a pump provided outside through the plurality of vacuum holes, the substrate support portion installed in the reaction space to support a plurality of substrates; a gas injection unit including a plurality of gas injection units arranged radially opposite to the substrate support portion so as to inject process gas into the reaction space; and a control unit for adjusting a chucking force of the substrate according to the type of gas supplied through the gas injection unit.

[0007] According to the substrate processing apparatus, in the control unit, by operating a valve for adjusting the degree of vacuum of the susceptor plate to an on or off state to control the chucking force of the substrate according to the type of gas supplied through the gas injection unit, the temperature of the substrate can be adjusted.

[0008] According to the substrate processing apparatus, in the control unit, before supplying the first gas through the gas injection unit, the valve for adjusting the degree of vacuum of the susceptor plate can be operated to an on state.

[0009] According to the substrate processing apparatus, in the control unit, before supplying the second gas through the gas injection unit, the valve for adjusting the degree of vacuum of the susceptor plate can be operated to an off state.

[0010] According to the substrate processing apparatus, in the control unit, by operating the gas supply valve of the gas injection unit to adjust the amount of gas injected into the process chamber and controlling the fixing force of the substrate, the temperature of the substrate can be adjusted.

[0011] According to the substrate processing apparatus, the susceptor plate can further include a plurality of gas supply holes.

[0012] According to the substrate processing apparatus, in the control unit, by supplying a purge gas through the plurality of gas supply holes and controlling the fixing force of the substrate, the temperature of the substrate can be adjusted.

[0013] A substrate processing method according to another aspect of the present invention for solving the above problems includes a process chamber in which a reaction space is formed; a susceptor plate, a plurality of vacuum holes formed on the upper surface of the susceptor plate, and a vacuum line connected to a pump provided outside through the plurality of vacuum holes, a substrate support portion installed in the reaction space to support a plurality of substrates; a gas injection unit including a plurality of gas injection units arranged radially opposite to the substrate support portion so as to inject a process gas into the reaction space; and a control unit that adjusts a chucking force of the substrate according to the type of gas supplied through the gas injection unit. A substrate processing method using a substrate processing apparatus, comprising loading the substrate into the process chamber and placing it on the substrate support portion; and forming a thin film on the substrate while controlling the fixing force of the substrate according to the type of gas injected into the reaction space.

[0014] According to the substrate processing method, in the step of forming the thin film, before supplying a first gas through the gas injection unit, while supplying a purge gas, by operating a valve for adjusting the degree of vacuum of the susceptor plate to an on state and controlling the fixing force of the substrate, the temperature of the substrate can be adjusted.

[0015] According to the substrate processing method, in the step of forming the thin film, before supplying the second gas through the gas injection unit, while supplying the purge gas, by operating the valve for adjusting the degree of vacuum of the susceptor plate to the off state to control the fixing force of the substrate, the temperature of the substrate can be adjusted.

[0016] According to the substrate processing method, in the step of forming the thin film, before supplying the third gas through the gas injection unit, while supplying the purge gas, the valve for adjusting the degree of vacuum of the susceptor plate is operated to the on or off state, but by operating the gas supply valve of the gas injection unit to adjust the amount of gas injected into the process chamber to control the fixing force of the substrate, the temperature of the substrate can be adjusted.

[0017] According to the substrate processing method, in the step of forming the thin film, before supplying the third gas through the gas injection unit, while supplying the purge gas, the valve for adjusting the degree of vacuum of the susceptor plate is operated to the on or off state, but by supplying the purge gas through a plurality of gas supply holes provided in the susceptor plate to control the fixing force of the substrate, the temperature of the substrate can be adjusted.

Advantages of the Invention

[0018] According to the substrate processing apparatus and the substrate processing method using the same according to an embodiment of the present invention made as described above, when using different precursors whose ALD windows do not overlap, the process time can be shortened, and a thin film with uniform thickness dispersion can be formed. Of course, the scope of the present invention is not limited by such effects.

Brief Description of the Drawings

[0019]

Figure 1

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BEST MODE FOR CARRYING OUT THE INVENTION

[0020] Hereinafter, with reference to the accompanying drawings, various preferred embodiments of the present invention will be described in detail.

[0021] The embodiments of the present invention are provided to more fully explain the present invention to those having ordinary knowledge in the art. The following embodiments can be modified into various other forms, and the scope of the present invention is not limited to the following embodiments. Rather, these embodiments are provided to further enrich and complete the present disclosure and to fully convey the idea of the present invention to those skilled in the art. Also, in the drawings, the thickness and size of each layer are exaggerated for convenience of explanation and clarity.

[0022] Hereinafter, a substrate processing apparatus 200 according to an embodiment of the present invention can be used as a thin film deposition apparatus for forming a thin film on a substrate S. For example, the substrate processing apparatus 200 may be used in a thin film deposition apparatus using atomic layer deposition (ALD). In some embodiments, the substrate processing apparatus 200 may be used in a thin film deposition apparatus that requires a high-temperature process.

[0023] FIG. 1 is a schematic cross-sectional view showing a substrate processing apparatus 200 according to an embodiment of the present invention, and FIG. 2 is a perspective view schematically showing a substrate support portion 230 disposed in the substrate processing apparatus 200 shown in FIG. 1.

[0024] Referring to FIGS. 1 and 2, a substrate processing apparatus 200 according to an embodiment of the present invention may include a process chamber 210, a gas injection unit 220, a substrate support unit 230, and a control unit 270.

[0025] The process chamber 210 may include a reaction space 212 therein for processing a substrate S. For example, the process chamber 210 is configured to maintain airtightness, and may be connected to a vacuum pump (not shown) via at least one exhaust port 214 so as to discharge the process gas in the reaction space 212 and adjust the degree of vacuum in the reaction space. A valve 216 may be formed in at least a part of the exhaust port 214 to control the degree of vacuum in the process chamber 210. The valve 216 may be formed, for example, in the form of a throttle valve, and can control the degree of vacuum by controlling the amount of air passing through the throttle body.

[0026] The process chamber 210 may be provided in various shapes. For example, it may include a side wall portion that defines the reaction space 212 and a lid portion located at the upper end of the side wall portion. Further, the process chamber 210 may include an openable and closable gate (not shown) in the side wall portion for the movement of the substrate S.

[0027] The gas injection unit 220 may be installed in the process chamber 210 so as to inject a process gas into the reaction space 212. For example, the gas injection unit 220 can inject the process gas supplied from the outside of the process chamber 210 into the reaction space 212. More specifically, the gas injection unit 220 may be installed above the process chamber 210 so as to face the susceptor plate 110 to inject the process gas onto the substrate S placed on the substrate support unit 230.

[0028] In some embodiments, the gas injection unit 220 may include a plurality of gas injection units 222, and may include at least one inlet hole formed in the upper layer or side portion to receive the supply of process gas from the outside, and a plurality of injection holes for injecting the process gas onto the substrate S. For example, the gas injection unit 220 may have various forms such as the form of a shower head or the form of a nozzle.

[0029] More specifically, the gas injection unit 220 is formed in a fan shape so that the substrate S moving in a circular orbit around the rotation axis of the substrate support unit 230 can sequentially pass through a plurality of process gas injection regions, and may include a plurality of gas injection units 222 each injecting any one of source gas, reaction gas, and purge gas.

[0030] For example, the plurality of gas injection units 222 may include a source gas injection unit 222a formed in a fan shape and having a plurality of gas injection holes formed in the gas injection surface for injecting source gas, and a reaction gas injection unit 222b formed in a fan shape and having a plurality of gas injection holes formed in the gas injection surface for injecting reaction gas. Further, a purge gas injection unit (not shown) for injecting purge gas may be included between the source gas injection unit 222a and the reaction gas injection unit 222b.

[0031] The substrate support unit 230 may be installed in the process chamber 210 to face the gas injection unit 220 so as to support the substrate S. For example, the substrate support unit 230 may be installed in the process chamber 210 to be movable up and down and / or rotatable. The substrate support unit 230 may include a susceptor plate 110 and a shaft 160. The substrate support unit 230 may also be referred to as a substrate support assembly.

[0032] In some embodiments, the substrate support unit 230 may be coupled to the process chamber 210 using a bellows structure (not shown) so that the airtightness of the process chamber 210 can be maintained when the shaft 160 moves up and down and / or rotates.

[0033] The susceptor plate 110 can include at least one placement groove 120 for placing the substrate S. For example, the placement groove 120 may be provided in the shape of a pocket groove in the susceptor plate 110. A plurality of placement grooves 120 may be formed in the susceptor plate 110. For example, the placement grooves 120 may be formed in an appropriate number in consideration of the size and processing speed of the susceptor plate 110, and are not limited to the number shown in FIG. 1, and may be provided in an appropriate number.

[0034] The substrate support portion 230 may be, for example, a vacuum chuck, and includes a plurality of vacuum holes 112 formed on the upper surface of the susceptor plate 110 and a vacuum line 162 connected to a pump 280 provided outside through the vacuum holes 112. For example, the substrate S may be placed on the susceptor plate 110 and fixed by the degree of vacuum adjusted by the plurality of vacuum holes 112. Generally, the degree of vacuum is constantly maintained during the progress of the process. However, in the present invention, when using two different precursors whose ALD windows do not overlap, the degree of vacuum can be controlled according to the type of process gas to adjust the process temperature of the substrate S. Hereinafter, with reference to FIGS. 3 to 6, a method for adjusting the process temperature of the substrate S will be specifically described later.

[0035] In some embodiments, in order to stably fix the substrate S, a vacuum line 162 connected to the upper surface and the placement groove 120 of the susceptor plate 110 is formed on the susceptor plate 110, and discharge ports (a plurality of vacuum holes 112) connected to such a vacuum line 162 may be formed in the placement groove 120 on the upper surface of the susceptor plate 110.

[0036] The shaft 160 can be coupled to the susceptor plate 110. For example, the shaft 160 may be coupled to the bottom surface or the center of the susceptor plate 110 and extend downward. Further, the shaft 160 can rotate so that the substrate S can revolve, and can be raised and lowered so that the substrate S can be moved up and down. For example, a driving device (not shown) can be coupled to the shaft 160, and by this driving device, the shaft 160 can rotate or move up and down. When the shaft 160 rotates or moves up and down, the susceptor plate 110 can also rotate or move up and down.

[0037] A plurality of lift pins 148 can be connected through the susceptor plate 110. For example, the lower end of the lift pin 148 is supported, and by the lift pin 148, when the susceptor plate 110 rises or falls, the position of the susceptor plate 110 can be adjusted.

[0038] Under the susceptor plate 110 in the process chamber 210, a heater 255 for heating the substrate S can be arranged. For example, the heater 255 can include various heating sources such as heating heating wires and cartridge heaters, and a plurality of them may be arranged. Further, under the susceptor plate 110 in the process chamber 210, a housing body 251 surrounding the side portion of the heater 255 and a quartz plate 253 supported on the housing body 251 can be arranged. For example, the housing body 251 can have a donut shape with a central portion being empty so that the shaft 160 passes through the central portion. Further, the housing body 251 can be supported on the bottom surface of the process chamber 210.

[0039] Although not shown, when the susceptor plate 110 descends due to the descent of the shaft 160, the lift pin 148 can be supported on the quartz plate 253. The substrate S can rise onto the susceptor plate 110 while being placed on the lift pin 148. Thereafter, the substrate S can be detached from the lift pin 148 by a transfer robot (not shown).

[0040] Conversely, when loading the substrate S into the process chamber 210, with the lift pins 148 raised above the susceptor plate 110, the substrate S can be placed on the lift pins 148 by a transfer robot (not shown). Thereafter, the susceptor plate 110 rises, and the substrate S can be placed on the susceptor plate 110.

[0041] A vacuum line 162 formed in the susceptor plate 110 can be formed in the shaft 160. By forming a valve 164 in at least a part of the vacuum line 162 formed along the shaft 160, during the progress of the process, the chucking force of the substrate S can be easily controlled only by controlling the valve 164. The valve 164 is formed, for example, in the form of a throttle valve and can control the degree of vacuum by controlling the amount of air passing through the throttle body. Alternatively, a separate throttle valve (not shown) can be connected between the vacuum line 162 and the valve 164 to control the chucking force of the substrate S.

[0042] Also, the substrate processing apparatus 200 includes a control unit 270. The control unit 270 can adjust the chucking force of the substrate S according to the type of gas supplied through the gas injection unit 220. Hereinafter, the operation of the control unit 270 and the substrate processing method thereby will be described with reference to FIGS. 3 to 8.

[0043] FIGS. 3 and 4 are schematic diagrams showing a substrate processing method according to an embodiment of the present invention, FIGS. 5 and 6 are schematic diagrams showing a substrate processing method according to a comparative example of the present invention, FIG. 7 is a graph showing the temperature change of a substrate using the substrate processing method according to an embodiment of the present invention, and FIG. 8 is a graph showing the temperature change of a substrate using the substrate processing method according to a comparative example of the present invention.

[0044] Referring to FIGS. 1 and 3, the control unit 270 of the present invention can control the fixing force of the substrate S by operating the valve 164 for adjusting the degree of vacuum of the substrate support unit 230 to an on or off state according to the type of process gas supplied through the gas injection unit 220. Specifically, before supplying the first precursor gas having the first ALD window through the gas injection unit 220, that is, when the substrate S is placed on the substrate support unit 230, after operating the valve 164 for adjusting the degree of vacuum of the susceptor plate 110 to the on state, the first thin film can be deposited on the substrate S.

[0045] Before supplying the second precursor gas having the second ALD window, which is different from the first precursor gas, after operating the valve 164 for adjusting the degree of vacuum of the susceptor plate 110 to the off state and when the stabilization is completed, the second thin film can be deposited on the substrate S on which the first thin film has been deposited. When controlling the valve 164 for adjusting the degree of vacuum of the susceptor plate 110 to the off state, a purge gas can be supplied into the process chamber 210 through the gas injection unit 220.

[0046] As described above, by controlling the valve 164 for adjusting the degree of vacuum of the vacuum chuck according to the types of process gases having different ALD windows, the effect of temperature control of the substrate S can be easily obtained.

[0047] Referring to FIGS. 1, 4(a) and 4(b), after the second thin film is deposited and before supplying the first precursor gas again without controlling the setting temperature of the heater 255 to be different, after operating the valve 164 for adjusting the degree of vacuum of the susceptor plate 110 to the on state, the first thin film can be deposited on the second thin film. When controlling the valve 164 for adjusting the degree of vacuum of the susceptor plate 110 to the on state, a purge gas can be supplied into the process chamber 210 through the gas injection unit 220.

[0048] Referring to the reverse side and FIG. 5, when not controlling the chucking force of the substrate S, depending on the type of process gas, the setting temperature of the heater 255 must be appropriately adjusted to control the temperature of the substrate S to fall within the ALD window region. In this case, as shown in FIGS. 6(a) and 6(b), in order to deposit the first precursor thin film and the second precursor thin film respectively, the stabilization time of the setting temperature of the heater 255 takes more than 1 hour each.

[0049] For example, referring to FIGS. 7 and 8, when supplying different types of process gases where the ALD windows do not overlap, simply by controlling the degree of vacuum of the vacuum chuck, the setting temperature of the heater 255 can be maintained constant. Thus, compared with the prior art, the stabilization time can be relatively shortened even further (shortened from more than 1 hour in the prior art to within 3 minutes). For example, due to the plurality of vacuum holes 112 formed on the susceptor plate 110, the heat transferred from the heater 255 to the substrate S is not evenly transferred. When the setting temperature of the heater 255 changes, the temperature stabilization time of the substrate S takes a long time. At this time, even by only controlling the degree of vacuum of the susceptor plate 110, the purge gas can move into the separation space between the lower surface of the substrate S and the susceptor plate 110, so the temperature stabilization time of the substrate S due to the convection phenomenon is shortened.

[0050] As another example, together with controlling the degree of vacuum of the susceptor plate 110, by operating the gas supply valve (not shown) of the gas injection unit 220 to control the amount of purge gas injected into the process chamber 210, the chucking force of the substrate S can be controlled. The purge gas can be supplied through the gas injection unit 220, but for the purpose of stabilizing the substrate temperature due to the convection phenomenon between the lower surface of the substrate S and the upper surface of the susceptor plate 110, the purge gas can also be supplied through a plurality of gas supply holes (not shown) separately formed on the upper surface of the susceptor plate 110. In this case, it is connected in a bypass form with the vacuum line 162, and the amount of purge gas can be appropriately controlled for the purpose of controlling the chucking force of the substrate S.

[0051] In addition to controlling the degree of vacuum of the susceptor plate 110, if the amount of purge gas supplied onto the lower surface or the upper surface of the substrate S is controlled, it is applicable also to a deposition method using three or more precursor gases having different ALD windows from each other. The amount of purge gas can be controlled using a gas control unit 270 connected to the gas injection unit 220, for example, a separate gas control device such as an MFC.

[0052] For example, after sequentially depositing a first thin film and a second thin film on the substrate S using a first precursor gas and a second precursor gas, before supplying a third gas through the gas injection unit 220, while supplying a purge gas, the valve 164 for adjusting the degree of vacuum of the susceptor plate 110 can be operated to an on or off state. At this time, by controlling the amount of purge gas, the fixing force of the substrate S can be controlled, and after the temperature of the substrate S is stabilized, a third thin film can be deposited on the second thin film while supplying a third precursor gas. Utilizing the method described above, in the control unit 270, according to the types of precursor gases having different ALD window regions from each other, the fixing force of the substrate S can be adjusted by combining various methods.

[0053] The present invention has been described with reference to the embodiments shown in the drawings, but these are merely exemplary, and it will be understood by those having ordinary knowledge in the relevant technical field that various modifications and equivalent other embodiments will be possible hereinafter. Therefore, the true technical protection scope of the present invention must be determined by the technical idea of the appended claims.

Explanation of Reference Numerals

[0054] 110 Susceptor plate 120 Mounting groove 160 Shaft 200 Substrate processing apparatus 210 Process chamber 220 Gas injection unit 230 Substrate support unit 270 Control unit 280 Pump

Claims

1. A process chamber having a reaction space formed therein, a susceptor plate, a plurality of vacuum holes formed on the upper surface of the susceptor plate, and a vacuum line connected to a pump provided outside through the plurality of vacuum holes, and a substrate support portion installed in the reaction space to support a plurality of substrates, a heater disposed under the susceptor plate in the process chamber to heat the substrate, a gas injection unit including a plurality of gas injection units disposed radially opposite to the substrate support portion to inject process gas into the reaction space, a control unit for adjusting the chucking force of the substrate, The control unit, when depositing different thin films using different precursor gases whose ALD windows do not overlap, adjusts the vacuum degree of the susceptor plate to be in an on or off state before supplying the precursor gas to control the chucking force of the substrate differently so as to adjust the temperature of the substrate differently according to the type of the precursor gas corresponding to the thin film while maintaining the set temperature of the heater constant. A substrate processing apparatus.

2. The control unit, operates a valve for adjusting the vacuum degree of the susceptor plate to an on state to maintain the temperature of the substrate within a first ALD window before supplying a first precursor gas through the gas injection unit to deposit a first thin film. The substrate processing apparatus according to claim 1.

3. The control unit, operates a valve for adjusting the vacuum degree of the susceptor plate to an off state to maintain the temperature of the substrate within a second ALD window that does not overlap with the first ALD window before supplying a second precursor gas through the gas injection unit to deposit a second thin film. The substrate processing apparatus according to claim 2.

4. The control unit, when operating a valve for adjusting the vacuum degree of the susceptor plate to an on or off state, operates a gas supply valve of the gas injection unit to adjust the amount of purge gas injected into the process chamber. The substrate processing apparatus according to claim 1.

5. The susceptor plate further includes a plurality of gas supply holes. The substrate processing apparatus according to claim 1.

6. The control unit, The substrate processing apparatus according to claim 5, wherein when operating a valve for adjusting the degree of vacuum of the susceptor plate to an on or off state, purge gas is supplied through the plurality of gas supply holes.

7. A process chamber having a reaction space formed therein, a susceptor plate, a plurality of vacuum holes formed on the upper surface of the susceptor plate, and a vacuum line connected to a pump provided outside through the plurality of vacuum holes, and a substrate support portion installed in the reaction space to support a plurality of substrates, a heater disposed under the susceptor plate in the process chamber to heat the substrate, a gas injection unit including a plurality of gas injection units disposed radially opposite to the substrate support portion to inject process gas into the reaction space, a control unit for adjusting the chucking force of the substrate, A substrate processing method using a substrate processing apparatus including: loading the substrate into the process chamber and placing it on the substrate support portion; forming different thin films using different precursor gases that do not overlap in the ALD window while controlling the fixing force of the substrate. In the step of forming the thin film, in order to adjust the temperature of the substrate differently according to the type of the precursor gas corresponding to the thin film while maintaining the set temperature of the heater constant, before supplying the precursor gas, a valve for adjusting the degree of vacuum of the susceptor plate is operated to an on or off state to control the fixing force of the substrate differently.

8. The step of forming the thin film includes: operating a valve for adjusting the degree of vacuum of the susceptor plate to an on state to maintain the temperature of the substrate within a first ALD window before supplying a first precursor gas through the gas injection unit to deposit a first thin film; operating a valve for adjusting the degree of vacuum of the susceptor plate to an off state to maintain the temperature of the substrate within a second ALD window that does not overlap with the first ALD window before supplying a second precursor gas through the gas injection unit to deposit a second thin film. The substrate processing method according to claim 7.

9. In the step of forming the thin film, The substrate processing method according to claim 7, wherein when operating a valve for adjusting the degree of vacuum of the susceptor plate to an on or off state, a purge gas is supplied through the gas injection unit.

10. In the step of forming the thin film, The substrate processing method according to claim 7, wherein when operating a valve for adjusting the degree of vacuum of the susceptor plate to an on or off state, the gas supply valve of the gas injection unit is operated to adjust the amount of purge gas injected into the process chamber.

11. In the step of forming the thin film, The substrate processing method according to claim 7, wherein when operating a valve for adjusting the degree of vacuum of the susceptor plate to an on or off state, a purge gas is supplied through a plurality of gas supply holes provided in the susceptor plate.

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