Epitaxial growth apparatus
By setting up multiple independent growth chambers and guiding gas flow structures in the epitaxial growth apparatus, the problem of poor epitaxial layer thickness uniformity was solved, the uniformity and cleanliness of the epitaxial layer were improved, and the yield of wafer products was increased.
Patent Information
- Application Number
- CN202520417845.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-11
- Publication Date
- 2026-01-23
- Estimated Expiration
- 2035-03-11
AI Technical Summary
When current epitaxial devices perform epitaxial growth on multiple silicon wafers simultaneously, the thickness uniformity of the epitaxial layer is poor, leading to a decrease in wafer product yield.
Design an epitaxial growth apparatus comprising multiple independent growth chambers, each chamber having a base. The grooved sidewall of the base has an obtuse angle with the bottom surface to reduce the contact area between the wafer and the sidewall. The flow of reactive gas is guided by front and rear baffles to ensure uniform distribution.
It improves the thickness consistency of epitaxial layers on multiple silicon wafers and the thickness uniformity of epitaxial layers on a single silicon wafer, thereby increasing the yield of wafer products and simplifying cleaning operations.
Smart Images
Figure CN223823736U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the technical field of semiconductor manufacturing, especially relates to a epitaxial growth device. BACKGROUND
[0002] The semiconductor integrated circuit (IC) industry has experienced exponential growth. The pace of that growth is expected to continue over the next decade. Advances in IC materials and design have produced generations of ICs with feature sizes smaller than those of previous generations. Generally, smaller feature sizes allow more components to be incorporated into a chip. In other words, as the size of the components decreases, more components can be incorporated into a given area of a chip. This increase in the number of components that can be incorporated into a chip has the effect of increasing the functionality of the chip. This is because more components can be incorporated into a chip, which means that more components can be used to perform a given function. This increase in the functionality of the chip is often referred to as an increase in the "density" of the chip. The size of the components, however, is not the only factor that affects the density of the chip. The size of the features that can be produced by the photolithography process also affects the density of the chip. The size of the features that can be produced by the photolithography process is referred to as the "geometry" of the chip. As the geometry of the chip decreases, the density of the chip increases. In other words, as the size of the features that can be produced by the photolithography process decreases, more components can be incorporated into a given area of the chip. This increase in the density of the chip is often referred to as an increase in the "geometry" of the chip.
[0003] With the increasing demand for special device manufacturing, substrates formed by epitaxial process have the advantages of low cost and low defects, and are more and more applied to the manufacturing of special devices. The silicon epitaxial multi-wafer furnace has higher epitaxial yield than the silicon epitaxial single-wafer furnace, and can perform epitaxial growth process on multiple silicon wafers at the same time. However, the current epitaxial device has a large difference in the thickness consistency of the epitaxial layer grown on the multiple silicon wafers when performing epitaxial growth process on the multiple silicon wafers at the same time, and the uniformity of the thickness of the epitaxial layer grown on the single silicon wafer is also poor, thereby reducing the yield of wafer products.
[0004] Therefore, how to improve the consistency of epitaxial layer growth in the epitaxial process of multiple silicon wafers, and improve the thickness consistency of the epitaxial layer grown on the single silicon wafer, thereby improving the epitaxial quality, so as to improve the yield of wafer products, is a technical problem to be solved at present. SUMMARY
[0005] The utility model provides a epitaxial growth device for improving the consistency of epitaxial layer growth in the epitaxial process of multiple silicon wafers, and improving the thickness consistency of the epitaxial layer grown on the single silicon wafer, thereby improving the epitaxial quality, so as to improve the yield of wafer products.
[0006] According to some embodiments, the utility model provides a epitaxial growth device, including:
[0007] The growth structure includes a plurality of independent growth chambers, each of which has a susceptor in the growth chamber, the susceptor includes a susceptor body and a groove in the susceptor body, the groove is used for carrying a wafer, and the included angle between the side wall of the groove and the bottom surface of the groove is greater than 90 degrees.
[0008] In some embodiments, the growth structure further includes a base, and a plurality of growth chambers are located on the base, and the plurality of growth chambers are distributed around the center of the base;
[0009] The epitaxial growth apparatus further includes an inlet pipe for transmitting reactive gases and a front baffle and a rear baffle distributed horizontally on opposite sides of the base, wherein the inlet pipe is located on the side of the front baffle away from the base along the horizontal direction.
[0010] In some embodiments, the front baffle is higher than the rear baffle in the vertical direction.
[0011] In some embodiments, the growth structure further includes a base tray located within the growth chamber and a base support shaft extending vertically through the base tray, the base being connected to the top of the base support shaft;
[0012] The front baffle is flush with the top of the base tray, and the rear baffle is flush with the bottom of the base tray.
[0013] In some embodiments, the base is circular;
[0014] Both the front baffle and the rear baffle are flat plate structures, and the end of the front baffle facing the base is arc-shaped, as is the end of the rear baffle facing the base.
[0015] In some embodiments, the growth structure further includes a top cover located vertically above the base, the top cover being inclined toward the inner surface of the base relative to the top surface of the base toward the top cover, and the vertical distance between the top surface of the base and the inner surface of the top cover gradually decreasing in a horizontal direction along the front baffle toward the rear baffle.
[0016] In some embodiments, the groove includes an inner groove and an outer groove distributed around the upper part of the inner groove and communicating with the inner groove, the inner groove being used to support the wafer;
[0017] The angle between the sidewall of the inner groove and the bottom surface of the inner groove is greater than 90 degrees.
[0018] In some embodiments, the angle between the sidewall of the inner groove and the bottom surface of the inner groove is in the range of 105 degrees to 150 degrees.
[0019] In some embodiments, the angle between the sidewall of the outer groove and the bottom surface of the inner groove is greater than 90 degrees.
[0020] In some embodiments, the angle between the sidewall of the inner groove and the bottom surface of the inner groove is greater than or equal to the angle between the sidewall of the outer groove and the bottom surface of the inner groove.
[0021] The epitaxial growth apparatus provided by this utility model, by setting multiple independent growth chambers in the growth structure, each growth chamber having a base, the base including a base body and a groove located in the base body, by setting the sidewall of the groove to have an angle greater than 90 degrees with the bottom surface of the groove, that is, the angle between the sidewall of the groove and the bottom surface of the groove is an obtuse angle, on the one hand, can reduce the contact area between the wafer and the sidewall of the groove during epitaxial growth, thereby reducing the difference in the thickness of the epitaxial layer grown on the wafer surface in different growth chambers due to the different contact areas between the wafer and the sidewall of the groove in different growth chambers, and improving the consistency of the thickness of the epitaxial layer grown on multiple wafers; on the other hand, by reducing the contact area between the wafer and the sidewall of the groove during epitaxial growth, the accumulation of reactive gas at the edge of the wafer can be reduced, thereby improving the thickness uniformity of the epitaxial layer grown on the wafer surface in a single growth chamber. Meanwhile, since the angle between the sidewall and the bottom surface of the groove is obtuse, the accumulation of reactive gas at the corner between the sidewall and the bottom surface of the groove can be reduced, and the accumulation of particulate matter generated by the chemical reaction of the reactive gas at the corner can be reduced, thereby simplifying the subsequent cleaning operation of the groove and improving the cleanliness of the groove. Attached Figure Description
[0022] Figure 1 This is a structural block diagram of the epitaxial growth apparatus in a specific embodiment of the present invention;
[0023] Figure 2 This is a top view schematic diagram of the epitaxial growth apparatus in a specific embodiment of the present invention;
[0024] Figure 3 This is a top view schematic diagram of the growth structure in a specific embodiment of the present invention;
[0025] Figure 4 This is a cross-sectional schematic diagram of the epitaxial growth apparatus in a specific embodiment of the present invention;
[0026] Figure 5 This is a cross-sectional schematic diagram of the base in a specific embodiment of the present invention. Detailed Implementation
[0027] The specific embodiments of the epitaxial growth apparatus provided by this utility model will be described in detail below with reference to the accompanying drawings.
[0028] This specific embodiment provides an epitaxial growth apparatus. Figure 1 This is a structural block diagram of the epitaxial growth apparatus in a specific embodiment of the present invention. Figure 2This is a top view schematic diagram of the epitaxial growth apparatus in a specific embodiment of the present invention. Figure 3 This is a top view schematic diagram of the growth structure in a specific embodiment of the present invention. Figure 4 This is a cross-sectional schematic diagram of the epitaxial growth apparatus in a specific embodiment of the present invention. Figure 5 This is a cross-sectional schematic diagram of the base in a specific embodiment of the present invention. For example... Figures 1-5 As shown, the epitaxial growth apparatus includes:
[0029] The growth structure 16 includes a plurality of independent growth chambers 23, each of which has a base 30. The base 30 includes a base body 52 and a groove located within the base body 52. The groove is used to support the wafer, and the angle between the sidewall of the groove and the bottom surface of the groove is greater than 90 degrees.
[0030] For example, the epitaxial growth apparatus includes an loading / unloading structure 10, a first wafer mounting stage 11, a second wafer mounting stage 12, a first robotic arm 13, a transition stage 14, a wafer transfer chamber 15, and a second robotic arm, wherein the second robotic arm is located within the wafer transfer chamber 15. During the epitaxial growth process on the wafer surface, the wafer is transferred from the loading / unloading structure 10 to the first wafer mounting stage 11 or the second wafer mounting stage 12, and then transferred by the first robotic arm 13 to the transition stage 14. Next, the second robotic arm transfers the wafer to the wafer transfer chamber 15. After the growth chamber 23 becomes available, the second robotic arm transfers the wafer back to the growth chamber 23 to complete the epitaxial layer growth process within the growth chamber 23.
[0031] This specific embodiment, by setting multiple independent growth chambers 23 in the growth structure, allows multiple wafers to be placed one by one within the multiple growth chambers 23, facilitating the simultaneous epitaxial layer growth process on multiple wafers and increasing the yield of the epitaxial growth apparatus. In this specific embodiment, "multiple" refers to two or more. The angle between the sidewall and bottom surface of the groove is greater than 90 degrees, i.e., the angle between the sidewall and bottom surface of the groove is an obtuse angle. On one hand, this reduces the contact area between the wafer and the sidewall of the groove during epitaxial growth, thereby reducing the difference in epitaxial layer thickness on the wafer surface in different growth chambers due to varying contact areas, improving the consistency of epitaxial layer thickness on multiple wafers. On the other hand, by reducing the contact area between the wafer and the sidewall of the groove during epitaxial growth, the accumulation of reactive gases at the edges of the wafer is reduced, thereby improving the uniformity of epitaxial layer thickness on the wafer surface within a single growth chamber. Meanwhile, since the angle between the sidewall and the bottom surface of the groove is obtuse, the accumulation of reactive gas at the corner between the sidewall and the bottom surface of the groove can be reduced, and the accumulation of particulate matter generated by the chemical reaction of the reactive gas at the corner can be reduced, thereby simplifying the subsequent cleaning operation of the groove and improving the cleanliness of the groove.
[0032] In some embodiments, the growth structure further includes a base 22, and a plurality of growth chambers 23 are located on the base 22, and the plurality of growth chambers 23 are distributed around the center of the base 22;
[0033] The epitaxial growth apparatus further includes an inlet pipe for transmitting reactive gases and a front baffle 20 and a rear baffle 21 distributed horizontally on opposite sides of the base 22. The inlet pipe is located on the side of the front baffle 20 away from the base along the horizontal direction.
[0034] In some embodiments, the front baffle 20 is higher than the rear baffle 21 in the vertical direction.
[0035] In some embodiments, the growth structure further includes a base tray 33 located within the growth chamber 23 and a base support shaft 32 extending vertically through the base tray 33, wherein the base 30 is connected to the top of the base support shaft 32;
[0036] The front baffle 20 is flush with the top of the base tray 33, and the rear baffle 21 is flush with the bottom of the base tray 33.
[0037] Specifically, such as Figure 2 andFigure 4 As shown, the epitaxial growth apparatus also includes the base 22, on which all the growth chambers 23 are disposed, and the plurality of growth chambers 23 are arranged at intervals along the horizontal direction on the base 22. The epitaxial growth apparatus also includes an inlet pipe for transmitting reactive gases and a front baffle 20 and a rear baffle 21 distributed horizontally on opposite sides of the base 22. The inlet pipe is located along the horizontal direction on the side of the front baffle 20 facing away from the base, so that the reactive gases enter the growth chambers 23 from above the front baffle 20, and unreacted reactive gases are discharged from above the rear baffle 21. The reactive gases undergo a chemical reaction to form the epitaxial layer covering the surface of the wafer. By providing the front baffle 20 and the rear baffle 21 on opposite sides of the base 22 along the horizontal direction, the front baffle 20 and the rear baffle 21 guide the direction of the reactive gas entering the growth chamber 23 and the flow direction of residual gas (including unreacted reactive gas and by-product gas generated during the generation of the epitaxial layer). That is, the front baffle 20 and the rear baffle 21 guide the flow of gas in the growth chamber 23, reducing the amount of reactive gas flowing below the base 30, so that the reactive gas can flow evenly through multiple growth chambers 23, thereby further improving the consistency of the thickness of the epitaxial layer grown on multiple wafers. Figure 2 The arrows in the diagram indicate the direction of flow of the reactant gas.
[0038] The growth chamber 23 is further provided with a base tray 33 surrounding the sidewalls and bottom surface of the base 30, and a base support shaft 32 connected to the base 30 and penetrating the base tray 33 vertically. The base support shaft 32 can drive the base 30 to rotate, thereby further improving the thickness uniformity of the epitaxial layer grown on the wafer surface on the base 30. In one example, the surface of the base support shaft 32 is also covered with a protective shell 31 to protect the base support shaft 32 from the influence of the external environment. By setting the base tray 33, the accumulation of reactive gases under the base 30 can be further reduced, thereby further improving the thickness uniformity of the epitaxial layer grown on the wafer surface. The front baffle 20 is flush with the top of the base tray 33, and the rear baffle 21 is flush with the bottom of the base tray 33. This can better guide the reactive gas to the top of the base 30, further reducing the reactive gas flowing to the bottom of the base 30, and also reducing the accumulation of residual gas below the base 30.
[0039] In order to further equalize the distribution of the reactive gases in the multiple growth chambers 23, in some embodiments, the base 22 is circular;
[0040] Both the front baffle 20 and the rear baffle 21 are flat plate structures, and the end of the front baffle 20 facing the base 22 is arc-shaped, as is the end of the rear baffle 21 facing the base 22.
[0041] In some embodiments, the growth structure 16 further includes a top cover 34 located vertically above the base 30, the top cover 34 being inclined relative to the top surface of the base 30 facing the top surface of the top cover 34, and the vertical distance between the top surface of the base 30 and the inner surface of the top cover 34 gradually decreasing in the horizontal direction along the front baffle 20 toward the rear baffle 21.
[0042] For example, such as Figure 4 As shown, the top cover 34 is located above the base 30, and a quartz plate 35 is also covered on the inner surface of the top cover 34 facing the base 30. The inner surfaces of the top cover 34 and the quartz plate 35 facing the base 30 are both inclined relative to the top surface of the base 30 facing the top cover 34, which can better disperse the reactive gas in each of the growth chambers 23.
[0043] In some embodiments, such as Figure 5 As shown, the groove includes an inner groove 50 and an outer groove 51 distributed around the upper part of the inner groove 50 and communicating with the inner groove 50. The inner groove 50 is used to support the wafer.
[0044] The angle between the sidewall of the inner groove 50 and the bottom surface 301 of the inner groove 50 is greater than 90 degrees.
[0045] In some embodiments, the angle between the sidewall of the inner groove 50 and the bottom surface 301 of the inner groove 50 is in the range of 105 degrees to 150 degrees.
[0046] In some embodiments, the angle between the sidewall of the outer groove 51 and the bottom surface 301 of the inner groove 50 is greater than 90 degrees.
[0047] In some embodiments, the angle between the sidewall of the inner groove 50 and the bottom surface 301 of the inner groove 50 is greater than or equal to the angle between the sidewall of the outer groove 51 and the bottom surface 301 of the inner groove 50.
[0048] For example, such as Figure 5As shown, the angle between the sidewall of the inner groove 50 and the bottom surface 301 of the inner groove 50 is the first included angle α, and the angle between the sidewall of the outer groove 51 and the bottom surface 301 of the inner groove 50 is the second included angle β. The sidewall of the groove has a stepped structure, thereby dividing the groove into the inner groove 50 and the outer groove 51, which is distributed around the upper part of the inner groove 50 and communicates with the inner groove 50. By keeping the angle (i.e., the first included angle α) between the sidewall of the inner groove 50 and the bottom surface 301 of the inner groove 50 in the range of 105 degrees to 150 degrees, it is possible to reduce the contact area between the wafer and the sidewall of the inner groove 50 while reducing the accumulation of reactive gas at the corner of the bottom of the inner groove 50. By making the angle (i.e., the second angle β) between the sidewall of the outer tank 51 and the bottom surface 301 of the inner tank 50 greater than 90 degrees (e.g., between 105 and 150 degrees), the accumulation of the reactive gas at the corner of the bottom of the outer tank 51 can be reduced, thereby making the distribution of the reactive gas on the wafer surface more uniform. In one example, both the first angle α and the second angle β are 135 degrees.
[0049] The epitaxial growth apparatus provided in this specific embodiment, by setting multiple independent growth chambers in the growth structure, each growth chamber having a base, the base including a base body and a groove located in the base body, by setting the sidewall of the groove to have an angle greater than 90 degrees with the bottom surface of the groove, that is, the angle between the sidewall of the groove and the bottom surface of the groove is an obtuse angle, on the one hand, can reduce the contact area between the wafer and the sidewall of the groove during epitaxial growth, thereby reducing the difference in the thickness of the epitaxial layer grown on the wafer surface in different growth chambers due to the different contact areas between the wafer and the sidewall of the groove in different growth chambers, and improving the consistency of the thickness of the epitaxial layer grown on multiple wafers; on the other hand, by reducing the contact area between the wafer and the sidewall of the groove during epitaxial growth, the accumulation of reactive gas at the edge of the wafer can be reduced, thereby improving the thickness uniformity of the epitaxial layer grown on the wafer surface in a single growth chamber. Meanwhile, since the angle between the sidewall and the bottom surface of the groove is obtuse, the accumulation of reactive gas at the corner between the sidewall and the bottom surface of the groove can be reduced, and the accumulation of particulate matter generated by the chemical reaction of the reactive gas at the corner can be reduced, thereby simplifying the subsequent cleaning operation of the groove and improving the cleanliness of the groove.
[0050] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.
Claims
1. An epitaxial growth apparatus, characterized in that, include: The growth structure includes multiple independent growth chambers, each of which has a base. The base includes a base body and a groove located within the base body. The groove is used to support a wafer, and the angle between the sidewall of the groove and the bottom surface of the groove is greater than 90 degrees.
2. The epitaxial growth apparatus according to claim 1, characterized in that, The growth structure also includes a base, and the plurality of growth chambers are located on the base and are distributed around the center of the base; The epitaxial growth apparatus further includes an inlet pipe for transmitting reactive gases and a front baffle and a rear baffle distributed horizontally on opposite sides of the base, wherein the inlet pipe is located on the side of the front baffle away from the base along the horizontal direction.
3. The epitaxial growth apparatus according to claim 2, characterized in that, In the vertical direction, the front baffle is higher than the rear baffle.
4. The epitaxial growth apparatus according to claim 2, characterized in that, The growth structure also includes a base tray located within the growth chamber and a base support shaft extending vertically through the base tray, the base being connected to the top of the base support shaft; The front baffle is flush with the top of the base tray, and the rear baffle is flush with the bottom of the base tray.
5. The epitaxial growth apparatus according to claim 4, characterized in that, The base is circular; Both the front baffle and the rear baffle are flat plate structures, and the end of the front baffle facing the base is arc-shaped, as is the end of the rear baffle facing the base.
6. The epitaxial growth apparatus according to claim 4, characterized in that, The growth structure also includes a top cover located vertically above the base, the top cover being inclined relative to the top surface of the base facing the top cover, and the vertical distance between the top surface of the base and the inner surface of the top cover gradually decreasing in the horizontal direction from the front baffle to the rear baffle.
7. The epitaxial growth apparatus according to claim 1, characterized in that, The groove includes an inner groove and an outer groove distributed around the upper part of the inner groove and communicating with the inner groove, the inner groove being used to support the wafer; The angle between the sidewall of the inner groove and the bottom surface of the inner groove is greater than 90 degrees.
8. The epitaxial growth apparatus according to claim 7, characterized in that, The angle between the sidewall of the inner groove and the bottom surface of the inner groove is in the range of 105 degrees to 150 degrees.
9. The epitaxial growth apparatus according to claim 7, characterized in that, The angle between the sidewall of the outer groove and the bottom surface of the inner groove is greater than 90 degrees.
10. The epitaxial growth apparatus according to claim 9, characterized in that, The angle between the sidewall of the inner groove and the bottom surface of the inner groove is greater than or equal to the angle between the sidewall of the outer groove and the bottom surface of the inner groove.