Method of manufacturing semiconductor element

Patent metadata

Field	Value
Publication number	US-2024258170-A1
Application number	US-202418422925-A
Country	US
Kind code	A1
Filing date	Jan 25, 2024
Priority date	Jan 27, 2023
Publication date	Aug 1, 2024
Grant date	—

Abstract

A method of manufacturing a semiconductor element includes irradiating a laser beam on a wafer, which includes a sapphire substrate having a first face and a second face opposite the first face and a semiconductor structure disposed on the first face, from a second face side. The laser beam irradiated along a first direction parallel to the second face of the sapphire substrate is focused inside the sapphire substrate to thereby create a modified portion in the sapphire substrate along the first direction. The wafer is severed and separated into a number of semiconductor elements following the formation of a modified portion. In the step of forming a modified portion, the laser beam is focused closer to the second face than to the first face in a thickness direction of the sapphire substrate.

First claim

What is claimed is:

1 . A method of manufacturing a semiconductor element, the method comprising:
a step of forming a modified portion inside a wafer comprising a sapphire substrate having a first face and a second face opposite the first face and a semiconductor structure disposed on the first face, the modified portion being formed inside the sapphire substrate along a first direction parallel to the second face by scanning a laser beam from a second face side along the first direction and focusing the laser beam inside the sapphire substrate; and subsequent to the step of forming the modified portion, a step of severing and separating the wafer into a plurality of semiconductor elements; wherein: in the step of forming the modified portion, the laser beam is focused to a position in a thickness direction of the sapphire substrate that is closer to the second face than to the first face; the sapphire substrate has a crystal structure that includes a plurality of crystal planes along (10-14) or (10-11) planes; an intensity distribution of the laser beam has an intensity peak in the first face of the sapphire substrate that is shifted from a center of the intensity distribution of the laser beam in a second direction intersecting the first direction, the second direction being, a direction, in a plan view, from (i) a given first point on a first intersecting line where the first face meets a third face along one of the plurality of crystal planes that is closest to being in parallel with the first direction towards (ii) a given second point on a second intersecting line where the third face meets the second face.

2 . The method of manufacturing a semiconductor element according to claim 1 wherein the intensity distribution of the laser beam is adjusted by generating comatic aberration.

3 . The method of manufacturing a semiconductor element according to claim 2 wherein the comatic aberration is controlled by the angle formed by the optical axis of a focusing lens and the incident-side laser beam rays.

4 . The method of manufacturing a semiconductor element according to claim 1 wherein the second direction is orthogonal to the first direction.

5 . The method of manufacturing a semiconductor element according to claim 2 wherein the second direction is orthogonal to the first direction.

6 . The method of manufacturing a semiconductor element according to claim 3 wherein the second direction is orthogonal to the first direction.

7 . The method of manufacturing a semiconductor element according to claim 1 wherein the second direction is orthogonal to the first intersecting line.

8 . The method of manufacturing a semiconductor element according to claim 2 wherein the second direction is orthogonal to the first intersecting line.

9 . The method of manufacturing a semiconductor element according to claim 3 wherein the second direction is orthogonal to the first intersecting line.

10 . The method of manufacturing a semiconductor element according to claim 1 wherein the first direction is parallel to an a-axis of the sapphire substrate.

11 . The method of manufacturing a semiconductor element according to claim 2 wherein the first direction is parallel to an a-axis of the sapphire substrate.

12 . The method of manufacturing a semiconductor element according to claim 3 wherein the first direction is parallel to an a-axis of the sapphire substrate.

13 . The method of manufacturing a semiconductor element according to claim 1 wherein the first direction is 45° oblique to an a-axis of the sapphire substrate.

14 . The method of manufacturing a semiconductor element according to claim 2 wherein the first direction is 45° oblique to an a-axis of the sapphire substrate.

15 . The method of manufacturing a semiconductor element according to claim 3 wherein the first direction is 45° oblique to an a-axis of the sapphire substrate.

Assignees

• Nichia Corp

Inventors

• Yamamoto Minoru
• Inoue Naoto
• Ibaraki Masayuki
• Tamemoto Hiroaki

Classifications

• H10P34/42

  with electromagnetic radiation, e.g. laser annealing (laser cutting H10P54/20) · CPC title

• H10P54/00 Primary

  Cutting or separating of wafers, substrates or parts of devices · CPC title

• H01L21/428

  Electricity · mapped topic

• H01L21/78 Primary

  Electricity · mapped topic