Chemical vapor deposition device for graphite substrate

Abstract

The utility model discloses a chemical vapor deposition device of a graphite substrate, which belongs to the technical field of LED (light-emitting diode) semiconductors, and is characterized in that a concave circular ring is arranged on the back surface of a carrying disc main body, and the temperature of a contact position of an epitaxial wafer and a plurality of bulges is close to the temperature of the middle of the epitaxial wafer by utilizing the principle that the heat conductivity of air is poorer than that of graphite, so that the wavelength uniformity is better. The carrier plate mainly comprises a carrier plate main body, a plurality of substrate placing ports are formed in the carrier plate main body, the substrate placing ports are annularly formed in the carrier plate main body, a plurality of supporting blocks are arranged in the substrate placing ports, and concave circular rings corresponding to the substrate placing ports are arranged on the carrier plate main body on the back faces of the substrate placing ports. The chemical vapor deposition device is mainly used for chemical vapor deposition of the graphite substrate.

Description

Technical Field

[0001] The utility model relates to the technical field of LED semiconductors, and in particular to a chemical vapor deposition device for a graphite substrate. Background Art

[0002] In recent years, the research direction of semiconductor devices based on GaN semiconductor materials has been very mature, and LED light-emitting diodes have formed a stable industrial chain. In order to further reduce costs and increase production capacity, the substrates used for LED epitaxial growth have gradually transitioned from 2 inches to 4 inches and 6 inches. Large-size substrates need to ensure good intra-chip uniformity, which requires higher temperature uniformity for epitaxial growth. The graphite substrate is the heat conduction medium between the substrate and the bottom heater. Therefore, the temperature uniformity and stability of the graphite substrate are of vital importance to the LED epitaxial industry. The epitaxial graphite substrate used to carry the substrate has a plurality of circular grooves distributed at intervals. The substrate is placed in the circular groove for growth, and an epitaxial substrate can be placed in each circular groove. For example, the substrate support device and epitaxial growth equipment with announcement number CN109411401B further reduce the heat conduction loss at the edge of the substrate by filling gas.

[0003] Since the thermal conductivity of the graphite carrier is significantly better than that of air, the temperature of the contact area between the epitaxial wafer and the circular groove is higher than that of other areas of the epitaxial wafer. Since the contact area between the substrate and the circular groove in the current graphite substrate is the edge, it is contacted through multiple protrusions, so that the temperature of the edge area of ​​the epitaxial wafer is relatively high, causing the wavelength of the edge area of ​​the epitaxial wafer to be shorter, and ultimately leading to uneven wavelength distribution of the epitaxial wafer. Summary of the invention

[0004] The purpose of the utility model is to provide a chemical vapor deposition device for a graphite substrate, which, by arranging a recessed circular ring on the back of a carrier body and utilizing the principle that the thermal conductivity of air is poorer than that of graphite, can make the temperature of the contact position between an epitaxial wafer and a plurality of protrusions close to the middle temperature of the epitaxial wafer, thereby improving the wavelength uniformity.

[0005] The utility model is realized by the following technical solutions:

[0006] A chemical vapor deposition device for a graphite substrate comprises a carrier body, on which a plurality of substrate placement openings are arranged in a ring shape on the carrier body, a plurality of support blocks are arranged in the substrate placement openings, and on the carrier body at the back of the plurality of substrate placement openings there are recessed circular rings corresponding to the plurality of substrate placement openings.

[0007] Furthermore, the depth of the same concave circular ring along the centrifugal direction gradually deepens, and the width of the concave circular ring along the centrifugal direction gradually widens.

[0008] Furthermore, the plurality of support blocks are arranged in a ring shape in the substrate placement opening.

[0009] Furthermore, the plurality of support blocks are in the shape of a triangle.

[0010] Furthermore, the width of the near-center circular ring region of the concave circular ring is greater than the width of the far-center circular ring region of the concave circular ring; the depth of the near-center circular ring region of the concave circular ring is greater than the depth of the far-center circular ring region of the concave circular ring.

[0011] Compared with the prior art, the beneficial effects of the utility model are:

[0012] 1. By setting a concave ring on the back of the carrier body and utilizing the principle that the thermal conductivity of air is worse than that of graphite, the temperature of the contact position between the epitaxial wafer and the multiple protrusions can be made close to the middle temperature of the epitaxial wafer, thereby improving the wavelength uniformity.

[0013] 2. By designing the concave ring to gradually deepen and widen along the centrifugal direction, the problem of high edge temperature caused by the contact between the epitaxial wafer and the carrier caused by the centrifugal force can be effectively improved, the problem of short edge wavelength can be solved, and the wavelength uniformity can be improved.

[0014] 3. Only by improving the structure of the carrier body, costs can be saved and production efficiency can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a front view schematic diagram of the utility model;

[0016] Figure 2 It is a rear view schematic diagram of the utility model;

[0017] Figure 3 It is a schematic diagram of the concave ring of the utility model.

[0018] In the figure: 1. substrate placement opening; 2. support block; 3. carrier body; 4. recessed ring; 5. substrate; 41. near-center ring area; 42. far-center ring area. DETAILED DESCRIPTION

[0019] The utility model is further described below in conjunction with the accompanying drawings.

[0020] like Figure 1 – Figure 3 As shown, embodiment 1, a chemical vapor deposition device for a graphite substrate, comprises a carrier body 3, a plurality of substrate placement openings 1 are provided on the carrier body 3, the substrate placement openings 1 are arranged in a ring shape on the carrier body 3, a plurality of support blocks 2 are provided in the substrate placement openings 1, and recessed circular rings 4 corresponding to the plurality of substrate placement openings 1 are provided on the carrier body 3 on the back side of the plurality of substrate placement openings 1.

[0021] Embodiment 2, a chemical vapor deposition device for a graphite substrate, wherein the depth of the same recessed circular ring 4 gradually deepens along the centrifugal direction, and the width of the recessed circular ring 4 gradually widens along the centrifugal direction; the width of the near-center circular ring area 41 of the recessed circular ring 4 is greater than the width of the far-center circular ring area 42 of the recessed circular ring 4; the depth of the near-center circular ring area 41 of the recessed circular ring 4 is greater than the depth of the far-center circular ring area 42 of the recessed circular ring 4; the plurality of support blocks 2 are arranged in a ring shape in the substrate placement port 1; the shape of the plurality of support blocks 2 is triangular, and the rest is the same as Embodiment 1.

[0022] The substrate 5 (epitaxial wafer) is placed on the support block 2. By setting a concave ring 4 on the back of the carrier body 3, the temperature of the contact position between the epitaxial wafer and the plurality of protrusions can be made close to the middle temperature of the epitaxial wafer by utilizing the principle that the thermal conductivity of air is poorer than that of graphite, so that the wavelength uniformity is better. By designing the concave ring 4 to gradually deepen in depth and gradually widen in width along the centrifugal direction, the problem of high edge temperature caused by the contact between the epitaxial wafer and the carrier body 3 due to centrifugal force can be effectively improved, and the problem of short edge wavelength can be solved, so that the wavelength uniformity is better.

Claims

1. A chemical vapor deposition device for a graphite substrate, comprising a carrier plate body (3), the carrier plate body (3) being provided with a plurality of substrate placement openings (1), characterized in that: The substrate placement opening (1) is arranged in a ring shape on a carrier body (3), a plurality of support blocks (2) are arranged in the substrate placement opening (1), and a recessed circular ring (4) corresponding to the plurality of substrate placement openings (1) is arranged on the carrier body (3) on the back side of the plurality of substrate placement openings (1).

2. The chemical vapor deposition device for graphite substrate according to claim 1, characterized in that: The depth of the concave circular ring (4) gradually increases along the centrifugal direction, and the width of the concave circular ring (4) gradually increases along the centrifugal direction.

3. The chemical vapor deposition device for graphite substrate according to claim 1, characterized in that: The plurality of support blocks (2) are arranged in a ring shape in the substrate placement opening (1).

4. The chemical vapor deposition device for graphite substrate according to claim 1, characterized in that: The plurality of support blocks (2) are in the shape of a triangle.

5. The chemical vapor deposition device for graphite substrate according to claim 2, characterized in that: The width of the near-center circular ring region (41) of the recessed circular ring (4) is greater than the width of the far-center circular ring region (42) of the recessed circular ring (4); the depth of the near-center circular ring region (41) of the recessed circular ring (4) is greater than the depth of the far-center circular ring region (42) of the recessed circular ring (4).

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