Epitaxial growth apparatus and gas supply control module used therein

Abstract

To provide an epitaxial growth apparatus, and a gas supply control module used therefor.SOLUTION: An epitaxial growth apparatus includes: a reaction chamber; a susceptor positioned in the reaction chamber and stably placing a wafer; and a gas supply control module for controlling the flow of gas flowing into the reaction chamber. The gas supply control module includes: an injector (210) including a center port (211) corresponding to the central area of the wafer, a pair of edge ports (213) corresponding to edge areas on both sides of the wafer and a pair of middle ports (215) arranged between the center port (211) and the pair of edge ports (213), respectively; and a flow rate distribution unit (230) constituted so as to independently distribute the flow rate of gas inputted from a source module to the ports (211, 213 and 215).SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to the technical field of epitaxial growth apparatus, and more particularly to an epitaxial growth apparatus and a gas supply regulation module used therein. [Background technology]

[0002] In general, epitaxial growth is the process of stacking new layers in a single crystal growth manner while maintaining the lattice direction on a seed wafer. Epitaxial growth requires a growth device that applies gas to the wafer.

[0003] The gas supply system of an epitaxial growth apparatus is composed of an injector, a baffle, an insert, and a liner, according to the procedure in which gas is injected from a gas tank into a chamber.

[0004] The important thing in gas supply is to form a uniform gas distribution in the chamber. This makes it possible to realize a uniform epitaxial layer thickness on a large area substrate (a substrate having a size of 6 inches or more). The uniformity of the epitaxial layer is preferably 1% or less. The epitaxial growth rate is also preferably 10 μm or more per minute.

[0005] However, the conventional gas supply system does not provide uniform gas distribution at the center and edge of the substrate, which results in thickness non-uniformity of the grown epitaxial layer of over 5%. Summary of the Invention [Problem to be solved by the invention]

[0006] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a gas injection apparatus that can form a uniform gas distribution over the entire area of ​​a substrate to grow a uniform epitaxial layer at a fast speed on a large area substrate. [Means for solving the problem]

[0007] According to one aspect of the present invention, there is provided an epitaxial growth apparatus including a reaction chamber; a susceptor disposed within the reaction chamber and configured to seat a wafer; and a gas supply control module configured to control a flow of gas flowing into the reaction chamber. The gas supply control module includes an injector having a center port corresponding to a central region of the wafer, a pair of edge ports corresponding to both side edge regions of the wafer, and a pair of middle ports disposed between the center port and the pair of edge ports; a single inlet line through which gas is input from a source module, five branch lines branching from the single inlet line and connected to each of the center port, the edge port, and the middle port; and a mass flow controller (MFC) connected to each of the ports. a flow distribution unit configured to distribute the gas independently to the ports and including a flow controller (not shown); and a baffle having through holes through which the gas inputted through the ports passes, the through holes including a first through hole corresponding to the center port, a second through hole corresponding to the middle port, and a third through hole corresponding to the edge port, and the first through hole, the second through hole, and the third through hole may have different shapes.

[0008] Here, the flow rate distribution unit may distribute the flow rates at the pair of edge ports and the pair of middle ports symmetrically with respect to the center port.

[0009] Here, an input end of the first through hole may have a smaller cross-sectional area than an input end of the second through hole, and an output end of the first through hole may have a larger cross-sectional area than an output end of the second through hole.

[0010] Here, an input end of the third through hole may have a smaller cross-sectional area than an input end of the second through hole, and an output end of the third through hole may have a smaller cross-sectional area than an output end of the second through hole.

[0011] Here, the first through hole may have a cross-sectional area of ​​the same size from its input end to its output end.

[0012] Here, the second through hole and the third through hole may have a cross-sectional area that decreases from the input end to the output end.

[0013] According to another aspect of the present invention, there is provided a gas supply control module for an epitaxial growth apparatus, the gas supply control module controlling a flow of a gas introduced into a reaction chamber of the epitaxial growth apparatus, the gas supply control module including: an injector having a center port corresponding to a central region of a wafer disposed in the reaction chamber, a pair of edge ports corresponding to edge regions on both sides of the wafer, and a pair of middle ports respectively disposed between the center port and the pair of edge ports; a flow distribution unit including a single inlet line through which a gas is input from a source module generating the gas, five branch lines branching from the single inlet line and connected to the center port, the edge port, and the middle port, respectively, and a mass flow controller connected to each of the ports, and configured to independently distribute the gas to the ports; and a baffle having passage holes through which the gas input through the ports passes, the passage holes including a first passage hole corresponding to the center port, a second passage hole corresponding to the middle port, and a third passage hole corresponding to the edge port, the first passage hole, the second passage hole, and the third passage hole may have different shapes.

[0014] Here, an input end of the first through hole may have a smaller cross-sectional area than an input end of the second through hole, and an output end of the first through hole may have a larger cross-sectional area than an output end of the second through hole.

[0015] Here, an input end of the third through hole may have a smaller cross-sectional area than an input end of the second through hole, and an output end of the third through hole may have a smaller cross-sectional area than an output end of the second through hole.

[0016] According to another aspect of the present invention, an epitaxial growth apparatus includes a reaction chamber; a susceptor located within the reaction chamber and configured to seat a wafer; and a gas supply control module configured to control a flow of gas flowing into the reaction chamber. The gas supply control module may include an injector having a center port corresponding to a central region of the wafer, a pair of edge ports corresponding to edge regions on both sides of the wafer, and a pair of middle ports respectively disposed between the center port and the pair of edge ports; and a flow rate distribution unit configured to independently distribute a flow rate of gas input from a source module to the ports.

[0017] Here, the flow distribution unit may include a mass flow controller connected to each of the ports, and may distribute the flow rates at the pair of edge ports and the pair of middle ports symmetrically with respect to the center port.

[0018] Here, the gas supply control module may further include a baffle having a passage hole through which the gas inputted through the port passes, the passage hole including a first passage hole corresponding to the center port, a second passage hole corresponding to the middle port, and a third passage hole corresponding to the edge port, and the first passage hole, the second passage hole, and the third passage hole may have different shapes. Effect of the Invention

[0019] According to the epitaxial growth apparatus and gas supply control module used therein constructed as above, the gas supply control module, which supplies gas to a wafer seated on a susceptor in a reaction chamber, distributes gas flow rates independently to each port through an injector having a center port and a pair of edge ports and a middle port disposed on the left and right sides of the center port, thereby forming a uniform gas distribution over the entire area of ​​a large area substrate, thereby enabling an epitaxial layer to grow uniformly at a high speed. [Brief description of the drawings]

[0020] [Figure 1] 1 is a conceptual diagram of an epitaxial growth apparatus according to an embodiment of the present invention; [Diagram 2] FIG. 2 is a perspective view showing a partial configuration of the epitaxial growth apparatus of FIG. [Diagram 3] FIG. 3 is a cross-sectional view showing the configuration related to the injector shown in FIG. 2. [Figure 4] FIG. 3 is a front view of the baffle and injector of FIG. 2. [Diagram 5] 5 is a cross-sectional view showing the shapes of the first through third passing holes in FIG. 4. FIG. [Figure 6] FIG. 2 is an image diagram showing the uniform gas flow achieved by the epitaxial growth apparatus of FIG. 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, an epitaxial growth apparatus and a gas supply control module used therein according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. In this specification, the same or similar reference numerals are used to refer to the same or similar components even in different embodiments, and the description thereof supersedes the first description.

[0022] FIG. 1 is a conceptual diagram of an epitaxial growth apparatus according to an embodiment of the present invention, and FIG. 2 is a perspective view showing a partial configuration of the epitaxial growth apparatus of FIG.

[0023] Referring to this figure, an epitaxial growth apparatus 100 includes a reaction chamber 110 , a susceptor 150 , a gas supply regulation module 200 , and a source module 300 .

[0024] The reaction chamber 110 has a reaction space where an epitaxial reaction takes place. The reaction space is simply represented by a rectangular box in the drawing, and specifically, a lower housing (not shown) and an upper housing (not shown) are stacked. The upper housing and the lower housing may be made of a transparent material such as quartz glass. Gas may be supplied to the left side of the reaction space by a gas supply control module 200, and gas may be discharged to the right side of the reaction space.

[0025] The susceptor 150 is located in the reaction space and is a target on which the wafer W is fixed. The susceptor 150 may have a flat disk shape. The susceptor 150 may be made of carbon graphite or a material in which carbon graphite is coated with silicon carbide. The wafer W is classified as a large area wafer since it has a size of 6 inches or 8 inches or more.

[0026] The gas supply regulation module 200 is configured to provide gases and regulate the flow of the gases into the reaction chamber 110. The gas supply regulation module 200 may include an injector 210, a flow rate distribution unit 230, a baffle 250, an insert 270, and a liner 290.

[0027] The injector 210 is configured to discharge the gas input from the source module 300 in a direction toward the reaction chamber 110. The injector 210 may be configured to discharge different amounts of gas depending on the region of the wafer W. A specific configuration for this purpose will be described with reference to FIG.

[0028] The flow rate distribution unit 230 distributes the gas flow rate input to the injector 210 to different regions of the injector 210. The gas flow rates for the different regions may be different, which will also be described in detail with reference to FIG.

[0029] The baffle 250 has through holes 251, 253, and 255 through which the gas inputted through the injector 210 passes. The through holes 251, 253, and 255 may have different shapes depending on the region of the injector 210. This will be described in more detail with reference to FIGS.

[0030] The insert 270 is disposed between the baffle 250 and the liner 290 and has a configuration that guides gas that has passed through the baffle 250 to the liner 290. The insert 270 may have multiple sections that allow gas to pass through.

[0031] The liner 290 has a configuration that surrounds the susceptor 150 and guides the gas to flow to the wafer W. To this end, the liner 290 may have a generally ring-like shape. One side of the liner 290 may be formed with a portion that discharges gas toward the wafer W, and the other side may be formed with a portion that discharges gas away from the wafer W.

[0032] The source module 300 may be a gas tank that stores the gas that must be supplied to the reaction chamber 110 or an intermediate distributor connected thereto.

[0033] The injector 210 and the flow rate distribution unit 230 will be described below with reference to Fig. 3. Fig. 3 is a cross-sectional view showing the injector-related configuration of Fig. 2.

[0034] With additional reference to this figure, the injector 210 has a center port 211, an edge port 213, and a middle port 215 as regions through which gas flows.

[0035] The center port 211 is located corresponding to a central region of the wafer W. The edge ports 213 may be provided in pairs corresponding to edge regions on both sides of the wafer W. The middle port 215 may be located between the center port 211 and the edge port 213. The middle ports 215 may also be provided in pairs located on both left and right sides of the center port 211. The left and right parts of the center port 211, the pair of edge ports 213, and the pair of middle ports 215 may be symmetrical with respect to an imaginary line L passing through the center of the center port 211. The ports 211, 213, and 215 may have the same volume as each other. Specifically, the ports 211, 213, and 215 may have the same width, depth, and height as each other.

[0036] The flow rate distribution unit 230 has an inlet line 231 and a branch line 235. The inlet line 231 is a line that communicates with the source module 300 and through which gas is input. Meanwhile, the branch lines 235 branch off from one (single) inlet line 231 and are connected to the ports 211, 213, and 215. Therefore, five branch lines 235 may be provided.

[0037] The flow rate distribution unit 230 has a mass flow controller (not shown) connected to each of the ports 211, 213, and 215. Five mass flow controllers are provided and installed in each branch line 235. The gas input amount to each port 211, 213, and 215 can be independently distributed according to the settings of each of the mass flow controllers. For example, the gas input amount to the center port 211 can be the lowest, and the gas input amount to the pair of edge ports 213 can be the highest. The gas input amount to the pair of middle ports 215 can be at an intermediate level therebetween. The flow rate distribution unit 230 may also distribute gas such that the input amounts to the pair of edge ports 213 and the pair of middle ports 215 are symmetrical to each other with respect to the center port 211.

[0038] Next, the baffle 250 that passes the gas flowing through the injector 210 in five regions toward the reaction chamber 110 will be described with reference to Figures 4 and 5. Figure 4 is a front view of the baffle and injector of Figure 2, and Figure 5 is a cross-sectional view showing the shapes of the first through third passing holes of Figure 4.

[0039] Referring to this figure, gas entering the baffle 250 through each port 211, 213, 215 passes through through holes 251, 253, 255.

[0040] The through holes 251 , 253 , and 255 include a first through hole 251 , a second through hole 253 , and a third through hole 255 .

[0041] The first through hole 251 is formed corresponding to the center port 211. The second through hole 253 is formed corresponding to the middle port 215. The third through hole 255 is formed corresponding to the edge port 213.

[0042] The first through hole 251 to the third through hole 255 may have different shapes. Specifically, the first through hole 251 has a cylindrical cross section that has the same cross section from the input end 251a to the output end 251b, whereas the second through hole 253 and the third through hole 255 may have a cone-shaped cross section. The cross sections of the second through hole 253 and the third through hole 255 are formed to become smaller in size from the injector 210 toward the insert 270.

[0043] Comparing the first through hole 251 and the second through hole 253, the input end 251a of the first through hole 251 may have a smaller cross-sectional area than the input end 253a of the second through hole 253. In contrast, the output end 251b of the first through hole 251 may have a larger cross-sectional area than the output end 253b of the second through hole 253. This configuration allows the speed of gas passing through the second through hole 253 to be higher than the speed of gas passing through the first through hole 251.

[0044] The input end 255a of the third through hole 255 may have a cross-sectional area smaller than or equal to the input end 253a of the second through hole 253, while the output end 255b may have a cross-sectional area smaller than the output end 253b of the second through hole 253. This configuration allows the velocity of gas passing through the third through hole 255 to be higher than the velocity of gas passing through the second through hole 253.

[0045] The gas flow in the reaction chamber 110 configured as above is as shown in Fig. 6. Fig. 6 is an image diagram showing the uniform gas flow achieved by the epitaxial growth apparatus of Fig. 1.

[0046] With additional reference to this figure, it can be seen in the computer simulation that the flow of gas relative to the wafer W is uniform over the entire area of ​​the wafer W. Specifically, the flow of gas is uniform over the center area, edge area, and areas therebetween of the wafer W.

[0047] This effect is achieved by, when supplying gas to a large-area wafer W, injecting gas differently from each of the five ports 211, 213, and 215 from the injector 210 corresponding to the wafer W, and by controlling the gas flow rate in the baffle 250 to be different for the ports 211, 213, and 215. In addition, by concentrating the gas flow on the surface of the wafer W, the concentration of the gas acting on the wafer W can be maximized.

[0048] The above gas flow rate distribution can solve the problem that the amount of gas decreases minutely and the gas velocity decreases from the center region to the edge region of the wafer W. This is particularly important for uniform gas distribution on substrates of 8 inches or more.

[0049] Also, the gas velocity can be maintained at 100 to 250 cm / sec depending on the shape of the through holes 251, 253, and 255. This allows a uniform gas flow to be obtained over the large area wafer W.

[0050] The epitaxial growth apparatus and the gas supply control module used therein are not limited to the configurations and operation methods of the above-mentioned embodiments, and the above-mentioned embodiments may be configured to be variously modified by selectively combining all or part of each embodiment. [Explanation of symbols]

[0051] 100 Epitaxial growth equipment 110 Reaction Chamber 150 Susceptor 200 Gas Supply Regulation Module 210 Injector 230 Flow Distribution Unit 250 Baffle 270 Insert 290 Liner

Claims

1. A reaction chamber; a susceptor positioned within the reaction chamber and configured to seat a wafer; and a gas supply regulating module configured to regulate the flow of gas into the reaction chamber; Including, The gas supply regulation module includes: an injector including a center port corresponding to a central region of the wafer, a pair of edge ports corresponding to edge regions on both sides of the wafer, and a pair of middle ports respectively disposed between the center port and the pair of edge ports; a flow distribution unit including a single inlet line through which gas is input from a source module, five branch lines branched from the single inlet line and connected to each of the center port, the edge port, and the middle port, and a mass flow controller connected to each of the ports, and configured to distribute the gas independently to the ports; and a baffle having through holes through which gas input via said port passes; Including, The passage hole is a first passage hole corresponding to the center port, a second passage hole corresponding to the middle port, and a third passage hole corresponding to the edge port; The first through hole, the second through hole, and the third through hole are They have different forms, The input end of the first through hole is The second through hole has a smaller cross-sectional area than the input end thereof, The output end of the first through hole is The second through hole has a cross-sectional area larger than the output end thereof. Epitaxial growth equipment.

2. The flow rate distribution unit includes:

2. The epitaxial growth apparatus according to claim 1, wherein the flow rates at the pair of edge ports and the pair of middle ports are distributed symmetrically with respect to the center port.

3. A reaction chamber; a susceptor positioned within the reaction chamber and configured to seat a wafer; and a gas supply regulating module configured to regulate the flow of gas into the reaction chamber; Including, The gas supply regulation module includes: an injector including a center port corresponding to a central region of the wafer, a pair of edge ports corresponding to edge regions on both sides of the wafer, and a pair of middle ports respectively disposed between the center port and the pair of edge ports; a flow distribution unit including a single inlet line through which gas is input from a source module, five branch lines branched from the single inlet line and connected to each of the center port, the edge port, and the middle port, and a mass flow controller connected to each of the ports, and configured to distribute the gas independently to the ports; and a baffle having through holes through which gas input via said port passes; Including, The passage hole is a first passage hole corresponding to the center port, a second passage hole corresponding to the middle port, and a third passage hole corresponding to the edge port; The first through hole, the second through hole, and the third through hole are They have different forms, The input end of the third through hole is The second through hole has a smaller cross-sectional area than the input end thereof, The output end of the third through hole is an epitaxial growth device having a cross-sectional area smaller than the output end of the second via hole;

4. The first passage hole is 2. The epitaxial growth apparatus of claim 1 having a cross-sectional area of ​​the same size from its input end to its output end.

5. A reaction chamber; a susceptor positioned within the reaction chamber and configured to seat a wafer; and a gas supply regulating module configured to regulate the flow of gas into the reaction chamber; Including, The gas supply regulation module includes: an injector including a center port corresponding to a central region of the wafer, a pair of edge ports corresponding to edge regions on both sides of the wafer, and a pair of middle ports respectively disposed between the center port and the pair of edge ports; a flow distribution unit including a single inlet line through which gas is input from a source module, five branch lines branched from the single inlet line and connected to each of the center port, the edge port, and the middle port, and a mass flow controller connected to each of the ports, and configured to distribute the gas independently to the ports; and a baffle having through holes through which gas input via said port passes; Including, The passage hole is a first passage hole corresponding to the center port, a second passage hole corresponding to the middle port, and a third passage hole corresponding to the edge port; The first through hole, the second through hole, and the third through hole are They have different forms, The second passage hole and the third passage hole are An epitaxial growth apparatus having a cross-sectional area that decreases from its respective input end to its output end.

6. A gas supply adjustment module for adjusting the flow of gases input into a reaction chamber of an epitaxial growth apparatus, an injector including a center port corresponding to a central region of a wafer disposed in the reaction chamber, a pair of edge ports corresponding to edge regions on both sides of the wafer, and a pair of middle ports respectively disposed between the center port and the pair of edge ports; a flow distribution unit including a single inlet line through which gas is input from a source module that generates the gas; five branch lines branched from the single inlet line and connected to each of the center port, the edge port, and the middle port; and a mass flow controller connected to each of the ports, the mass flow distribution unit being configured to independently distribute the gas to the ports; and a baffle having through holes through which gas input via said port passes; Including, The passage hole is a first passage hole corresponding to the center port, a second passage hole corresponding to the middle port, and a third passage hole corresponding to the edge port; The first through hole, the second through hole, and the third through hole are They have different forms, The input end of the first through hole is The second through hole has a smaller cross-sectional area than the input end thereof, The output end of the first through hole is a gas supply adjusting module for an epitaxial growth apparatus, the module having a cross-sectional area larger than the output end of the second passage hole; 7. A gas supply regulation module for regulating the flow of gases introduced into a reaction chamber of an epitaxial growth apparatus, comprising: an injector including a center port corresponding to a central region of a wafer disposed in the reaction chamber, a pair of edge ports corresponding to edge regions on both sides of the wafer, and a pair of middle ports respectively disposed between the center port and the pair of edge ports; a flow distribution unit including a single inlet line through which gas is input from a source module that generates the gas; five branch lines branched from the single inlet line and connected to each of the center port, the edge port, and the middle port; and a mass flow controller connected to each of the ports, the mass flow distribution unit being configured to independently distribute the gas to the ports; and a baffle having through holes through which gas input via said port passes; Including, The passage hole is a first passage hole corresponding to the center port, a second passage hole corresponding to the middle port, and a third passage hole corresponding to the edge port; The first through hole, the second through hole, and the third through hole are They have different forms, The input end of the third through hole is The second through hole has a smaller cross-sectional area than the input end thereof, The output end of the third through hole is a gas supply adjusting module for an epitaxial growth apparatus, the module having a cross-sectional area smaller than the output end of the second passage hole;

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