Semiconductor processing equipment

Abstract

The present invention relates to the field of semiconductor processing, and discloses a semiconductor processing device, including a base, a shell and a wafer boat. The base is provided with a gas injection port, the shell is provided with a gas extraction port, the shell covers the outer side of the wafer boat, and a gas injection disk is provided above each supporting platform of the wafer boat, the gas injection disk includes an upper disk body and a lower disk body rotating at the bottom of the upper disk body, a pressurized airway and an impeller cavity are provided inside the upper disk body, the pressurized airway is communicated with the gas injection port, an impeller fixed to the lower disk body is provided inside the impeller cavity, an air distribution cavity communicated with the impeller cavity is provided inside the lower disk body, and a strip-shaped air distribution port is provided at the bottom of the air distribution cavity. The present invention can solve the problem of the uniformity of the film thickness during the wafer deposition process in the prior art, or adopts a method of gas diffusion contact from the outer periphery to the center of the wafer, or adopts a method of wafer rotating in a large amount of gas environment to contact the gas, all of which have the situation that the thickness of the deposited film edge is greater than the center thickness, and the film thickness still has the problem of unevenness.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor processing, and in particular to a semiconductor processing device. Background Art

[0002] One of the important links in the process of manufacturing semiconductor wafers into chips is deposition, which is to deposit layers of thin films on the wafer, and then carve out circuit networks that realize various functions on the thin films. The deposition method is mainly chemical vapor deposition, referred to as CVD, which mainly converts the coating material into precursor gas and reaction gas. The precursor gas and reaction gas form thin film materials through chemical reactions in the environment and then deposit them on the surface of the wafer. In the current market, the performance and low power consumption of electronic products are increasingly required, which requires more "fine" semiconductors to support them. If smaller and lower energy-consuming semiconductors are used, more functions can be added to electronic products. To achieve the miniaturization of semiconductors, thin film layers deposited from different materials are required, so that different parts inside the chip can perform their respective functions. Whether the thickness of the thin film deposited on the surface of the wafer is uniform has a particularly significant impact on the quality of subsequent chips.

[0003] Among the current technologies for depositing wafers, patent CN113186514B discloses a method in which wafers are stacked on a wafer boat and then placed vertically in a tube structure as a whole. Gas is injected from bottom to top in the tube body. The gas injection is carried out using two arc-shaped gas injection hole groups symmetrically distributed on the outside of the wafer boat. Each gas injection hole group includes multiple gas injection holes. The gas injection holes are distributed at intervals on the gas injection tube, and the angle between the axial direction of the gas injection hole and the flow direction of the gas in the gas injection tube gradually increases or decreases, so that the injected gas is evenly distributed around the outside of the wafer boat, which ensures the uniform gas distribution around the wafer on the wafer boat to a certain extent. However, it is impossible to ensure uniform gas distribution at the edge and center of the wafer. Due to the small gap between the stacked wafers on the wafer boat, there is a small amount of gas distribution between the wafers, and the gas distribution at the edge and the middle is uneven, resulting in the problem that the thickness of the film on the final wafer is uneven, with the thickness at the edge being greater than the thickness at the center. There is also a technology disclosed in patent CN113178374B, which uses a main turntable driven by a planetary gear train, and a plurality of sub-turntables connected to the planetary shafts are rotatably connected on a support plate, and the sub-turntables are used to carry wafers. In this way, multiple wafers are carried on a plane, and a spraying device is arranged above the main turntable. Multiple wafers rotate to receive the gas sprayed above. In this way, the gas distribution will be relatively uniform. However, the wafer is always rotating as a carrier for deposition, and the deposited film still has a situation where the middle thickness is smaller than the edge thickness, and the lateral area occupied is large, so it can only be used as a single-layer structure. If it is necessary to deposit multiple wafers at the same time, the overall structure occupies a large area, and the number of wafers deposited at the same time is limited, which is difficult to meet the needs of semiconductor mass production.

[0004] The existing solutions to the problem of uniform film thickness during wafer deposition include either using gas diffusion from the outside to the center of the wafer or rotating the wafer in a large gas environment to contact the gas. However, the thickness of the deposited film at the edge is greater than the thickness at the center, and the film thickness is still uneven. Summary of the invention

[0005] The present invention is intended to provide a semiconductor processing device to solve the problem of uniform film thickness during wafer deposition in the prior art, which is to use a method of gas diffusion from the outside to the center of the wafer, or a method of rotating the wafer in a large amount of gas environment to contact the gas. In both cases, the thickness of the deposited film edge is greater than the thickness in the center, and the film thickness is still uneven.

[0006] To achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a semiconductor processing equipment, including a base, a shell and a crystal boat, the shell and the crystal boat can be detachably connected to the base, a gas injection port is provided on the base, a gas exhaust port is provided on the shell, the shell covers the outside of the crystal boat, the crystal boat includes several layers of support platforms arranged vertically side by side, a gas injection disk is provided above each layer of support platform, the gas injection disk includes an upper disk body detachably fixedly connected to the crystal boat, and a lower disk body rotatably connected to the bottom of the upper disk body, a pressurized air duct and an impeller cavity are connected inside the upper disk body, the pressurized air duct is connected to the gas injection port, an impeller is coaxially fixed with the lower disk body is provided in the impeller cavity, an air distribution cavity connected to the impeller cavity is provided inside the lower disk body, and a strip air distribution port with a length of 70%-90% of the wafer radius is opened at the bottom of the air distribution cavity.

[0007] The principles and advantages of this solution are: in actual application, the base provides bottom support and positioning for the wafer boat, the shell and the base form a closed space required for deposition, the base is used for gas injection, and the gas enters the gas injection disk through the internal channel of the wafer boat. The gas injection disk evenly spreads the gas on the surface of the wafer, and the waste gas after deposition is completed is extracted from the shell. The gas injection disk converts the gas injection pressure into power to drive the impeller to rotate, driving the lower disk to rotate and distribute gas, and the gas is synchronously and evenly sprayed in the radial direction of the wafer through the strip gas distribution port of a specific size from above the wafer in a rotating manner. The gas distribution in the radial direction of the wafer is more uniform, and the rotation method allows the gas to sweep and cover all areas of the wafer circumference, ensuring that the gas is evenly distributed in the center and outer edge of the wafer, and then it can be deposited on the wafer to form a thin film of uniform thickness.

[0008] Preferably, as an improvement, the crystal boat includes a base and a top plate, a plurality of columns are detachably connected between the base and the top plate, the plurality of columns are evenly distributed in a ring shape, a gas injection interlayer connected to the gas injection port is provided in the base, a gas injection channel connected to the gas injection interlayer is provided in the column, a plurality of gas injection holes are vertically arranged side by side on the column, and the gas injection holes connect the gas injection channel and the pressurized gas channel.

[0009] The detachable connected columns facilitate the installation of the gas injection plate. The gas injection interlayer, gas injection channel, and gas injection holes form a multi-level gas diversion structure, which evenly disperses the gas into each gas injection plate and enters the impeller cavity through the pressurized air channel to drive the impeller to rotate. This uses a hidden gas path and has a neater appearance.

[0010] Preferably, as an improvement, a plurality of slots spaced apart from the support platform are vertically arranged side by side on the column, the side ends of the upper plate body are inserted into the slots, and the gas injection holes are located at the bottom of the slots. The slot connection method makes the installation operation of the gas injection plate simpler and more convenient, and more convenient for batch operation.

[0011] Preferably, as an improvement, a plurality of strip-shaped gas distribution ports are evenly distributed in a ring shape, so that the gas distribution on the wafer is more uniform and efficient.

[0012] Preferably, as an improvement, a mounting groove is provided at the upper end of the base, the gas injection port is located in the middle of the mounting groove, the base is plugged into the mounting groove, and a gas injection port is provided in the middle of the base to connect the gas injection interlayer and the gas injection port. In this way, the gas path can be connected by plugging and positioning the base in the mounting groove, and the operation is convenient and simple.

[0013] Preferably, as an improvement, the impeller cavity is located in the middle of the upper disk body, and a plurality of pressurized air passages are arranged around the impeller cavity, the number of which is the same as the number of the columns, and the pressurized air passages are arranged obliquely along the tangent direction of the impeller shaft. This ensures that the gas is ejected from the pressurized air passage, and the ejected gas can more fully impact the blades to drive the impeller to rotate.

[0014] Preferably, as an improvement, a plurality of pressure relief hole groups are arranged around the impeller shaft at the bottom of the impeller cavity, the pressure relief hole group includes a plurality of pressure relief holes connecting the impeller cavity and the air distribution cavity, a fan-shaped air injection area is arranged between adjacent pressure relief hole groups, and the connecting end of the pressurized air duct and the impeller cavity is located in the air injection area. The gas enters the impeller cavity from the pressurized air duct to drive the blades to rotate, and then enters the air distribution cavity from the pressure relief hole group. The air injection area serves as the air inlet end of the impeller cavity, which is more conducive to improving the conversion of gas kinetic energy into impeller kinetic energy.

[0015] Preferably, as an improvement, the number of blades of the impeller is greater than the number of the pressure relief hole groups, so that at least one blade is present in any gas injection area, thereby ensuring that the gas ejected from the pressurized gas passage can reliably and effectively drive the impeller to rotate.

[0016] Preferably, as an improvement, the opening of the pressurized airway at the outer edge of the upper disk is a bell mouth, so that the gas discharged from the air injection hole can stably and effectively enter the pressurized airway, and the gas can be ejected from the bell mouth after entering the pressurized airway to more effectively impact drive the blade.

[0017] Preferably, as an improvement, an exhaust interlayer connected to the exhaust port is provided inside the shell, and a plurality of exhaust holes connected to the exhaust interlayer are provided on the inner wall of the shell, and the exhaust holes are arranged horizontally toward the wafer boat. In this way, the exhaust gas is discharged from the side, and the exhaust gas can be stably, effectively, quickly and completely exhausted for a plurality of wafers stacked vertically. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a longitudinal cross-sectional view of an embodiment of the present invention.

[0019] Figure 2 for Figure 1 A magnified schematic diagram of center A.

[0020] Figure 3 4 is a cross-sectional view of a gas injection disk in an embodiment of the present invention.

[0021] Figure 4 for Figure 3 Magnified view at B.

[0022] Figure 5 It is a top perspective view of the upper disk body in an embodiment of the present invention.

[0023] Figure 6 It is a bottom view of the lower plate in the embodiment of the present invention. DETAILED DESCRIPTION

[0024] The following is further described in detail through specific implementation methods:

[0025] The figure marks in the drawings of the specification include: base 1, gas injection port 2, base 3, gas injection interlayer 4, gas injection port 5, support bar 6, gas injection channel 8, gas injection hole 9, exhaust port 12, top plate 13, column 14, shell 15, exhaust interlayer 16, exhaust hole 17, gas injection disk 18, upper disk body 19, pressurized air channel 20, lower disk body 21, strip air distribution port 22, impeller 23, impeller shaft 24, blade 25, impeller cavity 26, air distribution cavity 27, pressure relief hole group 28, gas injection area 29, pressure relief hole 30, lubricating copper sleeve 31.

[0026] The embodiment is basically as shown in the attached Figure 1 , Figure 2 As shown: A semiconductor processing device, including a base 1, a shell 15 and a wafer boat, a mounting groove is provided at the upper end of the base 1, the wafer boat is inserted into the mounting groove, a gas injection port 2 is provided at the bottom of the mounting groove, the shell 15 covers the base 1 and the outer side of the wafer boat, and the inner wall of the bottom of the shell 15 is in frictional contact with the outer wall of the base 1. A gas extraction port 12 is provided at the top of the shell 15, and a gas extraction interlayer 16 connected to the gas extraction port 12 is provided inside, and a plurality of gas extraction holes 17 connected to the gas extraction interlayer 16 are provided on the inner wall of the shell 15, and the gas extraction holes 17 are arranged horizontally toward the wafer boat.

[0027] The wafer boat includes a base 3 and a top plate 13. Four columns 14 are bolted between the base 3 and the top plate 13. The four columns 14 are evenly distributed in a ring shape. The base 3 is inserted into the installation groove. A gas injection interlayer 4 is provided in the base 3. A gas injection port 5 connecting the gas injection interlayer 4 and the gas injection port 2 is provided in the middle of the base 3. Twenty slots and support bars 6 arranged at intervals are vertically arranged side by side on the column 14. The top surface of the support bar 6 is a plane. The support bars 6 on the four columns 14 form a support platform for supporting the wafer. A gas injection channel 8 connected to the gas injection interlayer 4 is provided in the column 14. A gas injection hole 9 connected to the gas injection channel 8 is provided at the bottom of each slot. A circular gas injection disk 18 inserted in the slot is provided above each layer of the support platform.

[0028] Combination Figure 3 , Figure 4 , Figure 5 As shown, the gas injection disk 18 includes an upper disk body 19 whose edge can be inserted into the slot, and a lower disk body 21 rotatably connected to the bottom of the upper disk body 19. An impeller cavity 26 is provided inside the upper disk body 19, and four pressurized air channels 20 are provided around the impeller cavity 26. The pressurized air channels 20 are inclined along the tangent direction of the impeller shaft 24. The opening of the pressurized air channel 20 at the outer edge of the upper disk body 19 is a bell mouth, which is aligned with and connected to the gas injection hole 9.

[0029] The impeller chamber 26 is provided with an impeller 23 coaxially fixed to the lower plate 21. Figure 6 As shown, the diameter of the lower plate 21 is smaller than that of the upper plate 19, and an air distribution cavity 27 is provided on the lower plate 21. The impeller shaft 24 is bolted to the middle of the air distribution cavity 27. A lubricating copper sleeve 31 is provided between the impeller shaft 24 and the upper plate 19. A strip air distribution port 22 with a length of 70%-90% of the wafer radius is provided at the bottom of the air distribution cavity 27. There are four strip air distribution ports 22 evenly distributed in a ring shape. Figure 5 As shown, the bottom of the impeller cavity 26 is provided with four pressure relief hole groups 28 around the impeller shaft 24. The pressure relief hole group 28 includes a plurality of pressure relief holes 30 connecting the impeller cavity 26 and the air distribution cavity 27. A fan-shaped gas injection area 29 is provided between adjacent pressure relief hole groups 28. The connecting end of the pressurized air channel 20 and the impeller cavity 26 is located in the gas injection area 29. The number of blades 25 of the impeller 23 is at least five, so that at least one blade 25 is present in any gas injection area 29.

[0030] The specific implementation process is as follows: During the assembly of the wafer boat, first install three columns 14 and then lay them horizontally, then insert several gas injection plates 18 into the slots on the columns 14, adjust the gas injection plates 18 so that the bell mouth of the pressurized air channel 20 is aligned with the gas injection hole 9, then place the wafers one by one between the support bar 6 and the gas injection plate 18, and then assemble the last column 14, and then lift the wafer boat upright through the hanging point on the top plate 13 of the wafer boat. The process should be operated at a low speed to avoid wafer damage. The wafer boat is hoisted into the installation groove on the base 1, the edge of the bottom plate is in contact with the side wall of the installation groove, the gas injection port 5 is aligned and connected with the gas injection port 2, and then the shell 15 is hoisted to the outside of the wafer boat and the base 1 through the top hanging point, the bottom of the shell 15 is in contact with the outer wall of the base 1, and the shell 15 covers the wafer boat and the base 1. When wafer deposition thin film processing is performed, gas enters from the gas injection port 2 of the base 1, enters the gas injection interlayer 4 in the wafer boat base 3 through the gas injection port 5, enters the gas injection channel 8 in the column 14 through the gas injection interlayer 4, and then enters the pressurized gas channel 20 from the gas injection hole 9 through the bell mouth. The gas is discharged from the pressurized gas channel 20 to impact the blades 25 in the impeller cavity 26 to drive the impeller 23 to rotate, and enters the pressure relief hole group 28 after passing through the gas injection area 29, and enters the gas distribution cavity 27 of the lower plate 21 from the pressure relief hole 30. The lower plate 21 rotates with the impeller 23, and the gas entering the gas distribution cavity 27 is evenly distributed to the wafer below from the strip gas distribution port 22. In this way, the wafer boat is improved, gas is injected from the inside of the wafer boat, and a special gas injection plate 18 is installed on the wafer boat without changing the placement of the wafers on the wafer boat. The wafer boat and the gas injection plate 18 provide a gas distribution structure that can rotate and scan above each wafer. The gas distribution can completely cover the wafer, so that the gas distribution in the radial direction of the wafer is uniform, which effectively improves the thickness uniformity of the thin film deposited on the wafer surface. At the same time, it has the function of batch deposition to meet the needs of mass production of semiconductor products.

[0031] The above is only an embodiment of the present invention, and the common knowledge such as the known specific technical solutions and / or characteristics in the solution is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the technical solution of the present invention, several modifications and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A semiconductor processing device, characterized in that: It includes a base, an outer shell and a crystal boat. The outer shell and the crystal boat can be detachably connected to the base. The base is provided with a gas injection port, the outer shell is provided with an exhaust port, and the outer shell covers the outside of the crystal boat. The crystal boat includes several layers of support platforms arranged vertically side by side. A gas injection disk is provided above each layer of support platforms. The gas injection disk includes an upper disk body detachably fixedly connected to the crystal boat, and a lower disk body rotatably connected to the bottom of the upper disk body. A connected pressurized air duct and an impeller cavity are provided inside the upper disk body. The pressurized air duct is connected to the gas injection port. An impeller coaxially fixed with the lower disk body is provided in the impeller cavity. An air distribution cavity connected to the impeller cavity is provided inside the lower disk body. A strip air distribution port with a length of 70%-90% of the wafer radius is provided at the bottom of the air distribution cavity.

2. A semiconductor processing device according to claim 1, characterized in that: The crystal boat includes a base and a top plate, and a plurality of columns are detachably connected between the base and the top plate. The plurality of columns are evenly distributed in a ring shape. A gas injection interlayer connected to the gas injection port is provided in the base, and a gas injection channel connected to the gas injection interlayer is provided in the column. A plurality of gas injection holes are vertically arranged side by side on the column, and the gas injection holes connect the gas injection channel and the pressurized gas channel.

3. A semiconductor processing device according to claim 2, characterized in that: A plurality of slots spaced apart from the support platform are vertically arranged side by side on the upright column, the side ends of the upper plate body are inserted into the slots, and the air injection holes are located at the bottom of the slots.

4. A semiconductor processing device according to claim 3, characterized in that: The strip-shaped air distribution ports are evenly distributed in a ring shape.

5. A semiconductor processing device according to claim 4, characterized in that: The upper end of the base is provided with a mounting groove, the gas injection port is located in the middle of the mounting groove, the base is plugged into the mounting groove, and the middle of the base is provided with a gas injection port connecting the gas injection interlayer and the gas injection port.

6. A semiconductor processing device according to claim 5, characterized in that: The impeller cavity is located in the middle of the upper disk body, and a plurality of pressurized air ducts are arranged around the impeller cavity. The number of pressurized air ducts is the same as the number of columns, and the pressurized air ducts are arranged obliquely along the tangent direction of the impeller shaft.

7. A semiconductor processing device according to claim 6, characterized in that: A plurality of pressure relief hole groups are arranged around the impeller shaft at the bottom of the impeller cavity, the pressure relief hole group includes a plurality of pressure relief holes connecting the impeller cavity and the air distribution cavity, a fan-shaped air injection area is arranged between adjacent pressure relief hole groups, and the connecting end between the pressurized air duct and the impeller cavity is located in the air injection area.

8. A semiconductor processing device according to claim 7, characterized in that: The number of blades of the impeller is greater than the number of the pressure relief hole groups, so that there is at least one blade in any gas injection area.

9. A semiconductor processing device according to claim 8, characterized in that: The opening of the pressurized airway located at the outer edge of the upper plate is a bell mouth.

10. The semiconductor processing equipment according to claim 1, characterized in that: An air extraction interlayer connected to the air extraction port is arranged inside the shell, and a plurality of air extraction holes connected to the air extraction interlayer are opened on the inner wall of the shell, and the air extraction holes are arranged horizontally toward the crystal boat.

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