Flow uniformizing plate for improving epitaxial thickness uniformity of single-chip furnace
By designing an optimized uniform plate, by adjusting the distribution and spacing of the first air intake hole and the second air intake hole, the problem of the thickness of the epitaxial layer in the prior art showing a ‘W’ shape along the radial distribution of the silicon wafer is solved, and the uniformity of the epitaxial sheet thickness is achieved.
Patent Information
- Application Number
- CN202422029651.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-21
- Publication Date
- 2025-06-06
- Estimated Expiration
- 2034-08-21
AI Technical Summary
The existing epitaxial furnace uniform plate design cannot effectively control the thickness of the silicon wafer R/2 point, resulting in the thickness of the epitaxial layer being distributed radially along the silicon wafer, affecting the thickness uniformity.
An optimized uniform plate is designed. By setting a first air intake hole and a second air intake hole, the two groups of first air intake holes and the second air intake holes are symmetrically distributed along the central axis of the homogenization plate body. The second air intake hole is located between the first air intake holes, and the spacing of the air intake holes is adjusted to achieve effective control of the thickness R/2 point of the silicon wafer.
By optimizing the through-hole distribution of the uniform flow plate, effective regulation of the thickness of the silicon wafer R/2 point is achieved, and the ‘W’ shape problem of the thickness of the epitaxial layer is solved along the radial distribution of the silicon wafer is significantly improved.
Smart Images
Figure CN222948516U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of silicon epitaxial growth equipment, and in particular designs a flow-distributing plate for improving the uniformity of epitaxial thickness of a single-chip furnace. Background Art
[0002] Epitaxial growth refers to growing one or more single crystal layers on a single crystal substrate with certain requirements and corresponding to the substrate lattice structure. At present, chemical vapor deposition is usually used for epitaxial growth.
[0003] like Figure 1 As shown, the existing epitaxial furnace air intake design is two-way air intake, Inner air path 1' and Outer air path 2', which are then connected to the air flow channel 4' through the flow plate 3' to achieve uniform distribution of the gas entering the reaction chamber. The through-hole spacing corresponding to the Inner and Outer air intakes of the conventional flow plate is the same. Since the base rotates at a certain speed during the epitaxial growth process, it is impossible to effectively control the silicon wafer thickness R / 2 point by only adjusting the ratio of the Inner and Outer air intakes, resulting in a "W"-shaped problem in the radial distribution of the epitaxial layer thickness along the silicon wafer. Utility Model Content
[0004] Purpose of the invention: In view of the above shortcomings, the utility model provides a flow plate for improving the uniformity of epitaxial thickness in a single-wafer furnace.
[0005] Technical solution: To solve the above problems, the utility model adopts a flow plate for improving the uniformity of epitaxial thickness of a single-wafer furnace, comprising a flow plate body, a plurality of first air inlet holes and a plurality of second air inlet holes arranged on the flow plate body, wherein the plurality of first air inlet holes are divided into two groups, and the two groups of first air inlet holes are symmetrically distributed along the central axis of the flow plate body, and the plurality of second air inlet holes are divided into two groups, and the two groups of second air inlet holes are symmetrically distributed along the central axis of the flow plate body, and the two groups of second air inlet holes are located between the two groups of first air inlet holes; the interval between two adjacent first air inlet holes in each group of first air inlet holes is l 1 The distance between two adjacent second air inlet holes in each group of second air inlet holes is l 2 , and l 2 <l 1 .
[0006] Furthermore, the centers of the cross sections of the first air inlet hole and the second air inlet hole are located on the same straight line, and the diameters of the first air inlet hole and the second air inlet hole are equal.
[0007] Furthermore, the flow plate body has a thickness of 14-16 mm, a width of 4-5 mm, and a length of 263-265 mm. The thickness direction is the radial direction of the air inlet hole, and the width direction is the axial direction of the air inlet hole.
[0008] Furthermore, the diameters of the first air inlet hole and the second air inlet hole are 4-6 mm, and the centers of the first air inlet hole and the second air inlet hole are 6-8 mm away from the upper end surface of the flow equalizer body.
[0009] Furthermore, the 1 15-17mm, l 2 The distance between the center of the outermost first air inlet hole and the edge of the flow plate body is 10-12 mm, and the distance between the center of the outermost second air inlet hole and the center of the innermost first air inlet hole is 21-23 mm.
[0010] Furthermore, the main body of the flow equalizer is made of quartz material.
[0011] Furthermore, the first air inlet hole and the second air inlet hole both penetrate the flow equalizer body from front to back.
[0012] Beneficial effect: Compared with the prior art, the significant advantage of the utility model is that it optimizes the distribution of through holes in the uniform flow plate by design, sets different spacings between the inner and outer air inlet holes, and a structure with denser inner air inlet holes, thereby achieving effective regulation of the silicon wafer thickness R / 2 point, solving the "W" shape problem of the radial distribution of the epitaxial layer thickness along the silicon wafer, improving the uniformity of the epitaxial wafer thickness, and providing an effective solution for high-quality epitaxial wafer processing. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 This is a schematic diagram of the air intake structure of an existing epitaxial furnace;
[0014] Figure 2 This is a side view of the flow equalizer of the utility model;
[0015] Figure 3 This is a side cross-sectional view of the flow equalizer of the utility model;
[0016] Figure 4 It is a cross-sectional view of the flow equalizer BB of the utility model. DETAILED DESCRIPTION
[0017] like Figures 2 to 4 As shown, a flow equalizer plate for improving the uniformity of epitaxial thickness of a single-wafer furnace in this embodiment includes a flow equalizer plate body 1, eight first air inlet holes and six second air inlet holes arranged on the flow equalizer plate body 1. The eight first air inlet holes are divided into two groups, and the two groups of first air inlet holes are symmetrically distributed along the central axis of the flow equalizer plate body 1; the six second air inlet holes are also divided into two groups, and the two groups of second air inlet holes are symmetrically distributed along the central axis of the flow equalizer plate body 1. The two groups of second air inlet holes are located between the two groups of first air inlet holes. Taking the left side of the flow equalizer plate as an example, four first air inlet holes (2, 3, 4, 5) distributed at equal intervals are provided on the flow equalizer plate body 1, with a spacing of l 1 There are three second air inlet holes (6, 7, 8) with an interval of l2 ; and l 2 <l 1 .
[0018] The centers of the cross sections of the first air inlet holes (2, 3, 4, 5) and the second air inlet holes (6, 7, 8) are located on the same straight line, and the diameters of the first air inlet holes and the second air inlet holes are equal. The flow equalizer body 1 is also provided with a threaded hole 9, and a bolt is installed in the threaded hole 9 to fix the flow equalizer to the air inlet end device.
[0019] In this embodiment, the thickness of the flow plate body 1 is 16mm, the width is 5mm, and the length is 265mm. The thickness direction is the radial direction of the air inlet hole, and the width direction is the axial direction of the air inlet hole. The diameter of the first air inlet hole and the second air inlet hole is 6mm, and the center of the first air inlet hole and the second air inlet hole is 8mm away from the upper end surface of the flow plate body 1. 1 15mm, l 2 The distance between the center of the first air inlet hole 2 located at the outermost side and the edge of the flow plate body 1 is 12 mm, and the distance between the center of the first air inlet hole 5 and the center of the second air inlet hole 6 is 23 mm.
[0020] The data in Tables 1 and 2 below compare the uniformity data of the existing flow equalizer and the flow equalizer of the utility model.
[0021] Table 1 Thickness uniformity data of different epitaxial layers of conventional flow plate
[0022]
[0023] Table 2 Improvement of the uniformity of thickness of different epitaxial layers of the flow plate
[0024]
[0025] The above data comparison shows that the uniformity of the improved flow plate can reach less than 0.5%, which is significantly improved. The utility model optimizes the through-hole distribution of the flow plate by designing and setting different spacings between the inner and outer air inlet holes and a more dense structure of the inner air inlet holes, thereby achieving effective control of the silicon wafer thickness R / 2 point, solving the "W" shape problem of the epitaxial layer thickness along the radial distribution of the silicon wafer, improving the uniformity of the epitaxial wafer thickness, and providing an effective solution for high-quality epitaxial wafer processing.
Claims
1. A flow plate for improving the uniformity of epitaxial thickness in a single-wafer furnace, characterized in that: The invention comprises a flow homogenizing plate body (1), a plurality of first air inlet holes and a plurality of second air inlet holes arranged on the flow homogenizing plate body (1), wherein the plurality of first air inlet holes are divided into two groups, and the two groups of first air inlet holes are symmetrically distributed along the central axis of the flow homogenizing plate body (1), and the plurality of second air inlet holes are divided into two groups, and the two groups of second air inlet holes are symmetrically distributed along the central axis of the flow homogenizing plate body (1), and the two groups of second air inlet holes are located between the two groups of first air inlet holes; the interval between two adjacent first air inlet holes in each group of first air inlet holes is l1, the interval between two adjacent second air inlet holes in each group of second air inlet holes is l2, and l2<l1.
2. The flow equalizer according to claim 1, characterized in that: The centers of the cross sections of the first air inlet hole and the second air inlet hole are located on the same straight line, and the diameters of the first air inlet hole and the second air inlet hole are equal.
3. The flow equalizer according to claim 2, characterized in that: The flow equalizer body (1) has a thickness of 14-16 mm, a width of 4-5 mm, and a length of 263-265 mm. The thickness direction is the radial direction of the air inlet hole, and the width direction is the axial direction of the air inlet hole.
4. The flow equalizer according to claim 3, characterized in that: The diameters of the first air inlet hole and the second air inlet hole are 4-6 mm, and the distance between the center of the first air inlet hole and the second air inlet hole and the upper end surface of the flow equalizing plate body (1) is 6-8 mm.
5. The flow equalizer according to claim 4, characterized in that: The l1 is 15-17 mm, the l2 is 10-12 mm, the distance between the center of the outermost first air inlet hole and the edge of the flow plate body (1) is 10-12 mm, and the distance between the center of the outermost second air inlet hole and the center of the innermost first air inlet hole is 21-23 mm.
6. The flow equalizer according to claim 1, characterized in that: The flow equalizer body (1) is made of quartz material.
7. The flow equalizer according to claim 1, characterized in that: The first air inlet hole and the second air inlet hole both penetrate the flow equalizer plate body (1) from front to back.