A quartz diffusion furnace for semiconductor silicon wafers

Abstract

The application belongs to the technical field of silicon wafer diffusion, and discloses a quartz diffusion furnace for semiconductor silicon wafers, which comprises a furnace body, a gas chamber arranged above the inner cavity of the furnace body, a plurality of uniformly distributed gas outlets and a plurality of gas outlet pipes in sliding connection with the gas chamber, a collision prevention mechanism arranged in the gas chamber and comprising a round rod symmetrically arranged on the outer wall of the gas outlet pipe and an extrusion block abutting against the outer wall of the round rod, and an adjusting mechanism arranged in the furnace body and comprising a supporting plate, a third double-wedge rod in linkage with the supporting plate through an inclined surface, a second double-wedge rod in meshing connection with the third double-wedge rod, and a first double-wedge rod in linkage with the second double-wedge rod and horizontally movable. The round rod is fixedly provided with a limiting block at the end thereof, and the first double-wedge rod extends to below the limiting block. When the semiconductor silicon wafer is placed on the supporting plate, the extrusion assembly extrudes the limiting block according to the weight of the silicon wafer so that the gas outlet pipes are at different heights. The application solves the problem that the existing equipment affects diffusion uniformity and yield after the size of the silicon wafer is adjusted.

Description

Technical Field

[0001] This invention relates to the field of silicon wafer diffusion technology, specifically to a quartz diffusion furnace for semiconductor silicon wafers. Background Technology

[0002] Diffusion furnaces are one of the important process equipment in the front-end of semiconductor production lines. They are used for diffusion, oxidation, annealing, alloying and sintering processes in industries such as large-scale integrated circuits, discrete devices, power electronics, optoelectronic devices and optical fibers.

[0003] Chinese patent application number 202123005186.4 discloses a "vertical diffusion furnace with uniform diffusion of reaction gas", which includes a vertical diffusion furnace body and a wafer body. A distribution box is provided on the left side of the vertical diffusion furnace body. The air inlet of the distribution box is connected to an air inlet pipe, and an air pump is provided on the air inlet pipe. A guide block is provided on the right side of the inner cavity of the distribution box. Air holes are opened at both the upper and lower ends of the distribution box. The two sets of air holes are connected to the upper and lower ends of the inner cavity of the vertical diffusion furnace body through a connecting pipe. The bottom ends of the two sets of connecting pipes are connected to a connecting pipe. The bottom ends of the two sets of connecting pipes are provided with an inner furnace tube. Several sets of air outlets are opened on one side of the inner furnace tube. The air outlet of the vertical diffusion furnace body is connected to an air outlet pipe.

[0004] Existing diffusion furnaces typically design their gas outlets according to the current size of semiconductor silicon wafers. The distance between the gas outlet and the semiconductor silicon wafer is moderate, allowing the gas to act evenly on the surface of the semiconductor silicon wafer and form a certain flow field distribution inside the furnace to achieve a uniform diffusion effect.

[0005] However, with the diversification of semiconductor silicon wafer sizes (such as the transition from 8 inches to 12 inches), the original balance is broken when the wafer size changes, which will affect diffusion uniformity and yield. Summary of the Invention

[0006] The purpose of this invention is to provide a quartz diffusion furnace for semiconductor silicon wafers. This invention solves the problem that existing equipment affects diffusion uniformity and yield after silicon wafer size adjustment.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a quartz diffusion furnace for semiconductor silicon wafers, comprising:

[0008] Furnace body;

[0009] The gas chamber is located above the inner cavity of the furnace body and includes several evenly distributed gas outlets and several gas outlet pipes that are slidably connected to the gas chamber.

[0010] The anti-collision mechanism is located inside the air chamber and includes round rods symmetrically arranged on the outer wall of the air outlet pipe and a pressing block abutting against the outer wall of the round rods.

[0011] The adjustment mechanism is located inside the furnace body and includes a support plate, a third double wedge rod that is linked to the support plate via an inclined surface, a second double wedge rod that meshes with the third double wedge rod, and a first double wedge rod that is linked to the second double wedge rod and can move horizontally.

[0012] A limiting block is fixedly installed at the end of the round rod, and the end of the first double wedge rod extends to the bottom of the limiting block; when the semiconductor silicon wafer is placed on the support plate, the extrusion assembly extrudes the limiting block according to the weight of the silicon wafer, so that the vent pipe is at different heights.

[0013] Preferably, a furnace door is slidably installed on the outer wall of the furnace body, and a capacitive sensor is installed on the outer wall of the furnace body.

[0014] Preferably, an air inlet pipe is installed on the upper surface of the furnace body, and the air inlet pipe is connected to the air chamber.

[0015] Preferably, the furnace body has a groove inside that matches the support plate, and a plurality of first springs are evenly installed on the outer wall of the groove, and the first springs are fixedly connected to the support plate.

[0016] Preferably, a hydraulic rod is fixedly installed on the outer wall of the furnace body, and a sliding plate is fixedly installed through the output shaft of the hydraulic rod through the furnace body. Slide rods are symmetrically installed on the side of the sliding plate away from the hydraulic rod, and the slide rods are fixedly connected to the extrusion block.

[0017] Preferably, a second spring is installed on the upper end face of the limiting block, and the side of the second spring away from the limiting block is installed on the furnace body.

[0018] Preferably, the inclined plane is symmetrically formed on the support plate.

[0019] Preferably, the third double wedge, the second double wedge, and the first double wedge are all slidably connected to the furnace body.

[0020] Preferably, the limiting block is slidably connected to the furnace body.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] 1. The present invention is provided with an adjustment mechanism. When the size of the semiconductor silicon wafer changes, the weight will change accordingly. The support plate will squeeze the first spring, causing it to deform. The inclined surface of the support plate will start to squeeze the third double wedge rod to move horizontally. The third double wedge rod squeezes the first double wedge rod to move horizontally through the second double wedge rod.

[0023] If the outer dimensions of the semiconductor silicon wafer increase and its weight increases, the first double wedge extends further, and the space for the limiting block to descend decreases, thus shortening the length of the vent pipe extending out of the gas chamber. Conversely, if the outer dimensions of the semiconductor silicon wafer decrease and its weight decreases, the first double wedge extends shorter, and the space for the limiting block to descend increases, thus lengthening the length of the vent pipe extending out of the gas chamber. This ensures that the vent pipe maintains an appropriate distance from the semiconductor silicon wafer, guaranteeing uniform gas distribution on the wafer surface and improving diffusion uniformity and yield.

[0024] Second, the present invention is equipped with an anti-collision mechanism. When the hydraulic rod extends, it pushes the slide plate to move in the air chamber. The slide plate drives the slide rod to move, and the slide rod drives the extrusion block to move. The extrusion block will extrude the round rod. The round rod drives the limiting block and the air outlet pipe to move upward. At this time, the limiting block extrudes the second spring, and the air outlet pipe retracts into the air chamber to prevent the quartz boat from colliding with the air outlet pipe when it is placed in, thus preventing damage. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0026] Figure 2 for Figure 1 Another perspective illustration;

[0027] Figure 3 This is a cross-sectional view of the present invention;

[0028] Figure 4 This is a schematic diagram of the internal structure of the furnace body of the present invention;

[0029] Figure 5 for Figure 4 Enlarged view of point A in the middle;

[0030] Figure 6 for Figure 4 Another perspective illustration;

[0031] Figure 7 This is a schematic diagram of the third double wedge rod, the second double wedge rod, and the first double wedge rod of the present invention.

[0032] In the diagram: 1. Furnace body; 2. Hydraulic rod; 3. Inlet pipe; 4. Furnace door; 5. Capacitive sensor; 6. Gas chamber; 7. Slide plate; 8. Outlet pipe; 9. Outlet; 10. Support plate; 11. First spring; 12. First double wedge rod; 13. Second double wedge rod; 14. Slide rod; 15. Extrusion block; 16. Round rod; 17. Second spring; 18. Limiting block; 19. Third double wedge rod; 20. Inclined surface. Detailed Implementation

[0033] To better understand the purpose, technical solution, and advantages of this application, the application is described and explained below in conjunction with the accompanying drawings and embodiments.

[0034] Please see Figures 1 to 7 The present invention provides a technical solution: a quartz diffusion furnace for semiconductor silicon wafers, comprising:

[0035] Furnace body 1;

[0036] The gas chamber 6 is located above the inner cavity of the furnace body 1, and includes several evenly distributed gas outlets 9 and several gas outlet pipes 8 that are slidably connected to the gas chamber 6.

[0037] The anti-collision mechanism is installed inside the air chamber 6 and includes round rods 16 symmetrically arranged on the outer wall of the air outlet pipe 8 and a pressing block 15 abutting against the outer wall of the round rods 16.

[0038] The adjustment mechanism is located inside the furnace body 1 and includes a support plate 10, a third double wedge rod 19 that is linked to the support plate 10 via an inclined surface 20, a second double wedge rod 13 that meshes with the third double wedge rod 19, and a first double wedge rod 12 that is linked to the second double wedge rod 13 and can move horizontally.

[0039] The end of the round rod 16 is fixedly installed with a limiting block 18, and the end of the first double wedge rod 12 extends to the bottom of the limiting block 18. When the semiconductor silicon wafer is placed on the support plate 10, the extrusion assembly extrudes the limiting block 18 according to the weight of the silicon wafer, so that the vent pipe 8 is at different heights.

[0040] Furthermore, such as Figure 2 As shown, a furnace door 4 is slidably installed on the outer wall of the furnace body 1, and a capacitive sensor 5 is installed on the outer wall of the furnace body 1.

[0041] In this embodiment, a pushing device is installed above the furnace door 4, which is existing technology. Its working principle is to realize the opening and closing action of the furnace door 4 through [brief principles, such as hydraulic drive, electric drive, etc.], so as to meet the needs of the diffusion furnace to open and close the furnace door 4 during operation.

[0042] Furthermore, such as Figure 2 As shown, an air inlet pipe 3 is installed on the upper surface of the furnace body 1. The air inlet pipe 3 is connected to the air chamber 6. A solenoid valve (not shown in the figure) is installed inside the air inlet pipe 3.

[0043] The air inlet pipe 3 is connected to the gas source equipment. After the solenoid valve is opened, the gas enters the gas chamber 6 from both sides, so that the output of the reaction gas is uniform.

[0044] Furthermore, such as Figure 3 and Figure 7 As shown, the furnace body 1 has a groove inside that is adapted to the support plate 10, and a plurality of first springs 11 are evenly installed on the outer wall of the groove. The first springs 11 are fixedly connected to the support plate 10.

[0045] The first spring 11 is used to reset the support plate 10. After the support plate 10 is reset, the second double wedge rod 13 descends and presses the third double wedge rod 19 back to the initial position. The limiting block 18 will press the first double wedge rod 12 back to the initial position.

[0046] Furthermore, such as Figure 3 and Figure 5 As shown, a hydraulic rod 2 is fixedly installed on the outer wall of the furnace body 1. The output shaft of the hydraulic rod 2 passes through the furnace body 1 and a sliding plate 7 is fixedly installed thereon. A sliding rod 14 is symmetrically installed on the side of the sliding plate 7 away from the hydraulic rod 2. The sliding rod 14 is fixedly connected to the extrusion block 15. A second spring 17 is installed on the upper end face of the limiting block 18. The side of the second spring 17 away from the limiting block 18 is installed on the furnace body 1.

[0047] When the hydraulic rod 2 is working, it drives the slide plate 7 to move, the slide plate 7 drives the slide rod 14 to move, the slide rod 14 drives the extrusion block 15 to move, and the extrusion block 15 extrudes or moves away from the round rod 16. At this time, the second spring 17 keeps the round rod 16 in contact with the extrusion block 15 through the limiting block 18.

[0048] Furthermore, such as Figure 6 As shown, the inclined plane 20 is symmetrically opened on the support plate 10, pressing the third double wedge rod 19.

[0049] Furthermore, such as Figure 7 As shown, the third double wedge rod 19, the second double wedge rod 13 and the first double wedge rod 12 are all slidably connected to the furnace body 1, and the limiting block 18 is slidably connected to the furnace body 1;

[0050] When the third double wedge rod 19 is squeezed, it moves horizontally and simultaneously squeezes the second double wedge rod 13. The second double wedge rod 13 moves vertically and squeezes the first double wedge rod 12, causing it to move horizontally. At this time, the end of the first double wedge rod 12 is below the limiting block 18, which will prevent the limiting block 18 from falling.

[0051] Working principle: Step 1: After connecting the external power supply and controller, first open the furnace door 4. At this time, the furnace door 4 is away from the capacitive sensor 5. After the capacitive sensor 5 feeds back to the controller, the hydraulic rod 2 extends and pushes the slide plate 7 to move in the air chamber 6. The slide plate 7 drives the slide rod 14 to move, and the slide rod 14 drives the extrusion block 15 to move. The extrusion block 15 will extrude the round rod 16. The round rod 16 drives the limit block 18 and the air outlet pipe 8 to move upward. At this time, the limit block 18 extrudes the second spring 17, and the air outlet pipe 8 retracts into the air chamber 6 to prevent the quartz boat from colliding with the air outlet pipe 8 and causing damage when it is placed in.

[0052] Step 2: Place the quartz boat containing the semiconductor silicon wafer onto the support plate 10. The support plate 10 compresses the first spring 11, and the inclined surface 20 of the support plate 10 will press the third double wedge rod 19. The third double wedge rod 19 presses the second double wedge rod 13, and the second double wedge rod 13 presses the first double wedge rod 12. At this time, the first double wedge rod 12 extends out below the limiting block 18.

[0053] Step 3: After the quartz boat is placed in, the furnace door 4 is closed. When the furnace door 4 comes into contact with the capacitive sensor 5, the capacitive sensor 5 feeds back to the controller. At this time, the hydraulic rod 2 retracts, causing the slide plate 7 to retract in the gas chamber 6. The slide plate 7 moves the slide rod 14, which in turn moves the extrusion block 15. The extrusion block 15 no longer extrudes the round rod 16. At this time, the second spring 17 extends, causing the limit block 18 and the gas outlet pipe 8 to move downwards. The limit block 18 stops when it comes into contact with the first double wedge rod 12. Then the furnace body 1 starts heating. When the required reaction gas needs to be introduced, the gas is introduced into the gas chamber 6 through the gas inlet pipe 3 connected to an external gas source. The gas is discharged into the furnace body 1 through the gas outlet pipe 8 and the gas outlet 9. Since the gas outlet pipe 8 and the gas outlet 9 are arranged in a rectangular shape above the furnace body 1, the gas will diffuse evenly in the furnace body 1, and the processing is finally completed.

[0054] Step 4: During reprocessing, if the external dimensions of the semiconductor silicon wafer change, the weight will change accordingly. The support plate 10 compresses the first spring 11, causing different deformations in the first spring 11. The support plate 10, through the inclined plane 20, compresses the third double wedge rod 19, which moves a certain distance. The third double wedge rod 19, through the second double wedge rod 13, compresses the first double wedge rod 12, which moves a certain distance, causing the end of the first double wedge rod 12 to extend below the limiting block 18. When the limiting block 18 descends, it abuts against the first double wedge rod 12. The round rod 16 drives the vent pipe 8 to extend a certain distance. At this time, the vent pipe 8 maintains an appropriate distance from the semiconductor silicon wafer, so that the gas acts uniformly on the surface of the semiconductor silicon wafer, improving diffusion uniformity and yield.

[0055] In this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, without necessarily requiring or implying any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0056] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A quartz diffusion furnace for semiconductor silicon wafers, characterized by comprising: Include: Furnace body (1); Gas chamber (6), provided above the inner cavity of the furnace body (1), comprising a plurality of uniformly distributed gas outlets (9) and a plurality of gas outlets (8) slidingly connected with the gas chamber (6); Anti-collision mechanism, provided inside the gas chamber (6), including a round rod (16) symmetrically arranged on the outer wall of the gas outlet pipe (8), and an extrusion block (15) abutting on the outer wall of the round rod (16); Adjusting mechanism, provided inside the furnace body (1), including a support plate (10), a third double wedge rod (19) linked with the support plate (10) through a slope (20), a second double wedge rod (13) meshing with the third double wedge rod (19), and a first double wedge rod (12) linked with the second double wedge rod (13) and horizontally movable; The end of the round rod (16) is fixedly installed with a limiting block (18), and the end of the first double wedge rod (12) extends below the limiting block (18); when the semiconductor silicon wafer is placed on the support plate (10), the extrusion assembly extrudes the limiting block (18) according to the weight of the silicon wafer, so that the gas outlet pipe (8) is at different heights.

2. A quartz diffusion furnace for semiconductor silicon wafers as claimed in claim 1, characterized in that: The outer wall of the furnace body (1) is slidingly installed with a furnace door (4), and the outer wall of the furnace body (1) is installed with a capacitive sensor (5).

3. The quartz diffusion furnace for semiconductor silicon wafers according to claim 1, characterized in that: The upper end surface of the furnace body (1) is installed with an air inlet pipe (3), and the air inlet pipe (3) is in communication with the gas chamber (6).

4. The quartz diffusion furnace for semiconductor silicon wafers according to claim 1, characterized in that: The inner part of the furnace body (1) is provided with a groove matched with the support plate (10), and the outer wall of the groove is uniformly installed with a plurality of first springs (11), and the first springs (11) are fixedly connected with the support plate (10).

5. The quartz diffusion furnace for semiconductor silicon wafers according to claim 1, characterized in that: The outer wall of the furnace body (1) is fixedly installed with a hydraulic rod (2), the output shaft of the hydraulic rod (2) penetrates the furnace body (1) and is fixedly installed with a sliding plate (7), the side away from the hydraulic rod (2) of the sliding plate (7) is symmetrically installed with a sliding rod (14), and the sliding rod (14) is fixedly connected with the extrusion block (15).

6. A quartz diffusion furnace for semiconductor silicon wafers as claimed in claim 1, wherein: The upper end surface of the limiting block (18) is installed with a second spring (17), and the side away from the limiting block (18) of the second spring (17) is installed on the furnace body (1).

7. The quartz diffusion furnace for semiconductor silicon wafers of claim 1 wherein: The slope (20) is symmetrically provided on the support plate (10).

8. The quartz diffusion furnace for semiconductor silicon wafers of claim 1 wherein: The third double wedge rod (19), the second double wedge rod (13) and the first double wedge rod (12) are all slidingly connected with the furnace body (1).

9. A quartz diffusion furnace for semiconductor silicon wafers as claimed in claim 8, characterized in that: The limiting block (18) is slidingly connected with the furnace body (1).

Images