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JP-7856553-B2 - Manufacturing method for semiconductor devices

JP7856553B2JP 7856553 B2JP7856553 B2JP 7856553B2JP-7856553-B2

Inventors

  • 南雲 裕司
  • 植茶 雅史
  • 奥田 勝

Assignees

  • 株式会社デンソー
  • トヨタ自動車株式会社
  • 株式会社ミライズテクノロジーズ

Dates

Publication Date
20260511
Application Date
20221206

Claims (4)

  1. A method for manufacturing a semiconductor device, A step of forming grooves (G) on the surface of an electrode layer (8) covering the first surface (2a) of a semiconductor substrate (2) by pressing a second scribing wheel (32) against the electrode layer , The process involves pressing a first scribing wheel (33) against the bottom surface of the groove to form a crack (5) in the semiconductor substrate that extends in the thickness direction of the semiconductor substrate, After the step of forming the crack, the semiconductor substrate is divided by pressing the dividing member (35) along the groove against the second surface (2b) of the semiconductor substrate located on the opposite side of the first surface, Equipped with , The first scribing wheel is rotatably supported by the first support member (133a), The second scribing wheel is rotatably supported by the second support member (132a), A manufacturing method wherein the play (C2) of the first scribing wheel relative to the first support in the direction along the axis of rotation of the first scribing wheel is greater than the play (C1) of the second scribing wheel relative to the second support in the direction along the axis of rotation of the second scribing wheel .
  2. The manufacturing method according to claim 1 , wherein the tip angle (A2) of the first scribing wheel is smaller than the angle (A1) defined by two straight lines connecting each of the two upper ends of the groove to the lower end of the groove in a cross section perpendicular to the groove.
  3. The manufacturing method according to claim 1 , wherein the tip angle (A2) of the first scribing wheel is smaller than the tip angle (A1) of the second scribing wheel.
  4. The manufacturing method according to any one of claims 1 to 3 , wherein the semiconductor substrate is made of SiC.

Description

The technology disclosed herein relates to a method for manufacturing semiconductor devices. One step in the manufacturing process of semiconductor devices is to separate a semiconductor substrate, on which multiple element structures are formed, into individual pieces. Patent Document 1 discloses a method called "scribing and breaking." In this method, first, a scribing wheel is pressed against the surface of the semiconductor substrate where the electrode layer is formed, applying a load in the thickness direction (hereinafter simply referred to as the thickness direction) of the semiconductor substrate. This forms a crack in the semiconductor substrate that extends along the thickness direction, along the boundary. Next, a dividing member is pressed along the boundary, dividing the semiconductor substrate into individual pieces, starting from the crack. Japanese Patent Publication No. 2021-193746 This is a plan view of a semiconductor substrate.This is a diagram illustrating the process of attaching the support plate.This is a diagram illustrating the grinding process before cracks are formed.This is a diagram illustrating the electrode formation process.This is a diagram illustrating the groove formation process.This is a diagram illustrating the crack formation process.This is a diagram illustrating how cracks are formed in Example 1.This is a diagram illustrating the process of applying dicing tape.This is a diagram illustrating the support plate removal process.This is a diagram illustrating the protective coating process.This is a diagram illustrating the division process.This is a diagram illustrating the pickup process.This is a diagram illustrating how cracks are formed in Example 2. In one example of a manufacturing method disclosed herein, the tip angle (A2) of the scribing wheel may be smaller than the angle (A1) defined by two straight lines connecting the two upper ends of the groove to the lower end of the groove in a cross-section perpendicular to the groove. This configuration makes it less likely for the scribing wheel to come into contact with the electrode layer, allowing for the formation of cracks that extend more appropriately along the thickness direction. In one example of a manufacturing method disclosed herein, the first scribing wheel is rotatably supported by a first support (133a), and the second scribing wheel is rotatably supported by a second support (132a). The play (C2) of the first scribing wheel relative to the first support in the direction along the axis of rotation may be greater than the play (C1) of the second scribing wheel relative to the second support in the direction along the axis of rotation. This configuration allows the first scribing wheel to easily follow the groove. Therefore, deviations of the first scribing wheel's movement path from the groove can be suppressed. (Example 1) The manufacturing method of Embodiment 1 will be described with reference to the drawings. Figure 1 is a plan view of a semiconductor substrate 2 in which a plurality of element regions 3 are formed in a matrix. In Figure 1, each element region 3 is schematically shown by a solid line. For the sake of explanation, the boundary between adjacent element regions 3, which will become the edge of each element region (semiconductor device) obtained by the division when the semiconductor substrate 2 is later divided into individual element regions 3, is called the planned division line 4. The planned division line 4 is not an actual line drawn on the semiconductor substrate 2, but a virtual line. The planned division line 4 may be an actual line or groove drawn on the semiconductor substrate 2 so as to be visible. A semiconductor element having a function such as a transistor or diode is formed in each element region 3. The semiconductor substrate 2 is made of silicon carbide (SiC). However, the semiconductor substrate 2 may also be made of other semiconductor materials such as silicon (Si) or gallium nitride (GaN). As shown in Figure 2, the semiconductor substrate 2 has a first surface 2a and a second surface 2b located on the back side of the first surface 2a. A main electrode 6 (source electrode, anode electrode, etc.) is formed on the second surface 2b of the semiconductor substrate 2. The manufacturing method in the example includes a support plate attachment step, a metal film formation step, a groove formation step, a crack formation step, a dicing tape attachment step, a support plate peeling step, a protective member coating step, and a division step. (Support plate attachment process) In the support plate attachment process, as shown in Figure 2, the support plate 12 is attached to the second surface 2b of the semiconductor substrate 2. The support plate 12 is attached to the second surface 2b via an adhesive 11. The support plate 12 is made of, for example, glass. The adhesive 11 is, for example, a silicon-based adhesive, and in addition to the function of bonding the semicon