Silicon carbide substrate with optimized surface layer

Abstract

The utility model discloses a silicon carbide substrate with an optimized surface layer, the silicon carbide substrate comprises a substrate body and at least one optimized surface layer, the substrate body is provided with at least one flaw surface, each optimized surface layer is integrally formed on each flaw surface of the substrate body, each optimized surface layer is made of silicon carbide, and each optimized surface layer is made of silicon carbide. Each optimized surface layer is formed by forming at least one unpolished silicon carbide layer on each flaw surface of the substrate body through a physical vapor deposition technique or a chemical vapor deposition technique, and then performing secondary polishing operation on each unpolished silicon carbide layer to form each optimized surface layer, thereby forming the silicon carbide substrate with the optimized surface layer. The problem of manufacturing end profit loss caused by an existing silicon carbide substrate with flaws on the surface is effectively solved, and the profit of the manufacturing end can be improved.

Description

Technical Field

[0001] The utility model relates to a silicon carbide substrate, in particular to a silicon carbide substrate with an optimized surface layer. Background Art

[0002] In the current semiconductor wafer manufacturing process, a silicon carbide substrate is generally formed by dividing a silicon carbide ingot through a splitting process and then grinding each ingot. The silicon carbide substrate is then subjected to subsequent epitaxial growth processes and device fabrication.

[0003] However, before SiC substrates are provided for subsequent epitaxial wafer processing and device fabrication, they undergo inspection to screen out those with surface defects. These defective SiC substrates are then relegated to lower-priced, inferior products. When these substrates are sold at the price of inferior products, the resulting profit loss for the manufacturing end can reach as high as approximately 70% of the original SiC substrate price, significantly impacting manufacturing profitability.

[0004] Therefore, a silicon carbide substrate with an optimized surface layer and a forming method thereof that can solve the problem of profit loss at the manufacturing end caused by silicon carbide substrates with surface defects are urgently awaited by the relevant industries. Utility Model Content

[0005] The main purpose of the present invention is to provide a silicon carbide substrate with an optimized surface layer, the silicon carbide substrate comprising a substrate body and at least one optimized surface layer, the substrate body having at least one defective surface, each of the optimized surface layers being integrally formed on each of the defective surfaces of the substrate body, each of the optimized surface layers being composed of silicon carbide, each of the optimized surface layers being formed by first forming at least one unpolished silicon carbide layer on each of the defective surfaces of the substrate body using a physical vapor deposition technique or a chemical vapor deposition technique, and then each of the unpolished silicon carbide layers being subjected to a second polishing operation to form each of the optimized surface layers, thereby forming a silicon carbide substrate with an optimized surface layer, effectively solving the problem of profit loss at the manufacturing end caused by existing silicon carbide substrates having surface defects.

[0006] To achieve the above objectives, the present invention provides a silicon carbide substrate with an optimized surface layer, characterized by comprising:

[0007] a substrate body, the substrate body being composed of silicon carbide and having at least one defective surface; wherein the substrate body is formed by dividing a silicon carbide ingot through a dividing operation and then undergoing a first grinding operation; and

[0008] At least one optimized surface layer, each optimized surface layer is composed of silicon carbide, and each optimized surface layer is integrally formed on each defective surface of the substrate body; wherein each optimized surface layer is formed on each defective surface of the substrate body by physical vapor deposition technology or chemical vapor deposition technology to form at least one unpolished silicon carbide layer, and each unpolished silicon carbide layer is subjected to a second polishing operation to form each optimized surface layer.

[0009] The utility model is beneficial to strengthening the strength of the structure and improving the yield rate of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic plan view of a side cross-section of the silicon carbide substrate of the present invention.

[0011] Figure 2 for Figure 1 A partial enlarged schematic diagram.

[0012] Figure 3 This is a three-dimensional schematic diagram of a substrate body of the present invention formed by cutting a silicon carbide ingot.

[0013] Figure 4 It is a schematic plan view of a side cross-section of the unground silicon carbide layer of the present invention after a second grinding operation to form an optimized surface layer.

[0014] Figure 5 This is a schematic flow chart of the method for forming a silicon carbide substrate of the present invention.

[0015] Explanation of reference numerals: 1-silicon carbide substrate; 1a-silicon carbide ingot; 10-substrate body; 11-defective surface; 20-optimized surface layer; 20a-unpolished silicon carbide layer. DETAILED DESCRIPTION

[0016] The structure and technical features of the present invention are described in detail below with reference to the accompanying drawings. The drawings are only used to illustrate the structural relationship and related functions of the present invention. Therefore, the sizes of the components in the drawings are not drawn according to the actual scale and are not intended to limit the present invention.

[0017] Please refer to Figure 1 and Figure 2 The present invention provides a silicon carbide substrate 1 with an optimized surface layer. The silicon carbide substrate 1 includes a substrate body 10 and at least one optimized surface layer 20 .

[0018] The substrate body 10 is made of silicon carbide (SiC) and has at least one defective surface 11 (e.g. Figure 1 and Figure 2wherein the substrate body 10 is formed by a silicon carbide ingot (Ingot) 1a which is divided by a splitting operation and then subjected to a first grinding operation (as shown); Figure 3 As shown), and after the first grinding operation, each of the defective surfaces 11 of the substrate body 10 is further subjected to a detection operation and is determined to have defects (such as Figure 5 The silicon carbide ingot 1a, also called a crystal rod, is formed in a crystal growth furnace. Since the silicon carbide ingot is a common technology, it will not be described in detail here.

[0019] Each of the optimized surface layers 20 is made of silicon carbide and is integrally formed on each of the defective surfaces 11 of the substrate body 10 (e.g. Figure 1 and Figure 2 ); wherein each optimized surface layer 20 is formed by first forming at least one unpolished silicon carbide layer 20a on each defective surface 11 of the substrate body 10 by physical vapor deposition (PCD) technology or chemical vapor deposition (CVD) technology, and then each unpolished silicon carbide layer 20a is subjected to a second polishing operation to form each optimized surface layer 20 (as shown); Figure 4 The physical vapor deposition technique or chemical vapor deposition technique is a technique for forming a thin film. Since both are common existing technologies, they will not be described in detail here.

[0020] Please refer to Figure 5 The forming method of the silicon carbide substrate 1 comprises the following steps:

[0021] Step S1: Provide a substrate body 10 (e.g., Figure 5 wherein the substrate body 10 is formed by a silicon carbide ingot 1a and is divided by a splitting operation (eg Figure 3 As shown) and then undergo a first grinding operation to form (as shown Figure 5 shown).

[0022] Step S2: At least one unpolished silicon carbide layer 20a (e.g., Figure 4 and Figure 5 shown).

[0023] Step S3: Perform a second grinding operation on each of the unpolished silicon carbide layers 20a, so that each of the unpolished silicon carbide layers 20a is ground and formed into at least one optimized surface layer 20 on each of the defective surfaces 11 of each of the substrate bodies 10 by the second grinding operation, thereby forming a silicon carbide substrate 1 with an optimized surface layer (such as Figure 4 and Figure 5 shown).

[0024] Compared with conventional silicon carbide substrates, the silicon carbide substrate 1 of the present invention has each optimized surface layer 20 integrally formed on each defective surface 11 of the substrate body 10. Each optimized surface layer 20 is composed of silicon carbide. Each optimized surface layer 20 is formed by first forming each unpolished silicon carbide layer 20a on each defective surface 11 of the substrate body 10 using a physical vapor deposition technique or a chemical vapor deposition technique. Each unpolished silicon carbide layer 20a is then subjected to a second polishing operation to form each optimized surface layer 20. This forms the silicon carbide substrate 1 having the optimized surface layer, resulting in the following advantages of the silicon carbide substrate 1 of the present invention:

[0025] (1) The silicon carbide substrate 1 of the present invention has the optimized surface layer 20, which effectively solves the problem of profit loss at the manufacturing end caused by existing silicon carbide substrates with surface defects, thereby helping to increase profits at the manufacturing end.

[0026] (2) Each of the optimized surface layers 20 of the present invention is integrally formed on each of the defective surfaces 11 of the substrate body 10 to optimize each of the defective surfaces 11 that were originally determined to be defects by the inspection operation, which is beneficial to strengthening the strength of the structure and improving the yield of the product, and helps to increase the market competitiveness of the product at the manufacturing end.

[0027] The above description is only a preferred embodiment of the present invention, which is merely illustrative and not restrictive of the present invention. A person skilled in the art will understand that many changes, modifications, and even equivalent changes may be made thereto within the spirit and scope defined by the claims of the present invention, but all of these changes will fall within the scope of protection of the present invention.

Claims

1. A silicon carbide substrate with an optimized surface layer, characterized in that: Include: a substrate body, the substrate body being composed of silicon carbide and having at least one defective surface; wherein the substrate body is formed by dividing a silicon carbide ingot through a dividing operation and then undergoing a first grinding operation; and At least one optimized surface layer, each optimized surface layer is composed of silicon carbide, and each optimized surface layer is integrally formed on each defective surface of the substrate body; wherein each optimized surface layer is formed on each defective surface of the substrate body by physical vapor deposition technology or chemical vapor deposition technology to form at least one unpolished silicon carbide layer, and each unpolished silicon carbide layer is subjected to a second polishing operation to form each optimized surface layer.

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