Method of manufacturing semiconductor device

Patent metadata

Field	Value
Publication number	US-10453687-B2
Application number	US-201816001159-A
Country	US
Kind code	B2
Filing date	Jun 6, 2018
Priority date	Jul 12, 2017
Publication date	Oct 22, 2019
Grant date	Oct 22, 2019

Abstract

A method of manufacturing a semiconductor device includes: forming, on a surface of an n-type semiconductor layer, an impurity source film containing both aluminum and beryllium; and forming a p-type impurity-doped layer in the n-type semiconductor layer by irradiating the impurity source film with first laser light to simultaneously introduce the aluminum and the beryllium into the n-type semiconductor layer.

First claim

What is claimed is:

1. A method of manufacturing a semiconductor device, comprising:
forming, on a surface of an n-type semiconductor layer, an impurity source film containing both aluminum and beryllium; and
forming a p-type impurity-doped layer in the n-type semiconductor layer by irradiating the impurity source film with first laser light to simultaneously introduce the aluminum and the beryllium into the n-type semiconductor layer.

2. The method of manufacturing a semiconductor device according to claim 1 , wherein the impurity source film is a single-layer film.

3. The method of manufacturing a semiconductor device according to claim 2 , wherein the impurity source film contains 0.1 atomic percent to 5 atomic percent of the beryllium.

4. The method of manufacturing a semiconductor device according to claim 2 , wherein the impurity source film has a thickness of 30 nm to 1 μm.

5. The method of manufacturing a semiconductor device according to claim 1 , wherein the impurity source film is a multilayer film in which an aluminum layer and a beryllium layer are laminated together.

6. The method of manufacturing a semiconductor device according to claim 5 , wherein the multilayer film is a two-layer film in which the beryllium layer and the aluminum layer are laminated in that order on the surface of the n-type semiconductor layer.

7. The method of manufacturing a semiconductor device according to claim 1 , wherein the irradiation with the first laser light is performed in a vacuum or in an inert gas.

8. The method of manufacturing a semiconductor device according to claim 1 , further comprising:
forming a metal film on a bottom surface of a supporting layer that is formed beneath the n-type semiconductor layer; and
irradiating the formed metal film with second laser light to promote silicidation between the metal film and the supporting layer.

9. The method of manufacturing a semiconductor device according to claim 1 , further comprising:
before forming the impurity source film, forming, on an upper surface of the n-type semiconductor layer, a mask for defining a region where the p-type impurity-doped layer is to be formed, wherein in the subsequent step of forming the impurity source film, the impurity source film is formed on the mask;
after irradiating with the first laser light, removing the mask to remove a residue of the impurity source film from the upper surface of the n-type semiconductor layer; and
forming a contact electrode on the upper surface of the n-type semiconductor layer from which the residue of the impurity source film has been removed.

10. The method of manufacturing a semiconductor device according to claim 1 , further comprising:
forming a metal film on a bottom surface of a supporting layer formed beneath the n-type semiconductor layer; and
forming a Schottky contact electrode by heating the formed metal film and the supporting layer.

11. The method of manufacturing a semiconductor device according to claim 1 , wherein the p-type impurity-doped layer formed in the n-type semiconductor layer has a ring shape as seen in a plan view.

12. The method of manufacturing a semiconductor device according to claim 1 , wherein the p-type impurity-doped layer formed in the n-type semiconductor layer has a plurality of line-shaped regions arranged parallel to one another with gaps therebetween in a plan view.

13. The method of manufacturing a semiconductor device according to claim 1 , wherein the n-type semiconductor layer is made of a silicon carbide semiconductor.

14. The method of manufacturing a semiconductor device according to claim 13 , wherein the silicon carbide semiconductor has any one of a 4H, 6H, or 3C monocrystalline structure or a polycrystalline structure.

15. The method of manufacturing a semiconductor device according to claim 1 , wherein the first laser light has a wavelength of greater than or equal to 190 nm.

16. The method of manufacturing a semiconductor device according to claim 1 , wherein a pulse width of the first laser light is 50 nanoseconds to 1 microsecond.

Assignees

• Fuji Electric Co Ltd

Inventors

• Iguchi Kenichi
• Nakazawa Haruo

Classifications

• H10P34/42

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

• H10P32/172

  being crystalline silicon carbide · CPC title

• H10P30/2042

  into crystalline silicon carbide · CPC title

• H10P30/21

  of electrically active species · CPC title

• H10D64/0123

  to silicon carbide · CPC title