Etching method for SiC substrate and holding container

Patent metadata

Field	Value
Publication number	US-10388536-B2
Application number	US-201515527622-A
Country	US
Kind code	B2
Filing date	Nov 17, 2015
Priority date	Nov 18, 2014
Publication date	Aug 20, 2019
Grant date	Aug 20, 2019

Abstract

Provided is a method for controlling the rate of etching of a SiC substrate based on a composition of a storing container. The etching method of the present invention is for etching the SiC substrate by heating the SiC substrate under Si vapor pressure, in a state where the SiC substrate is stored in a crucible. The crucible is formed of a tantalum metal, and has a tantalum carbide layer provided on an internal space side of the tantalum metal, and a tantalum silicide layer provided on the side further toward the internal space side than the tantalum carbide layer. The rate of etching of the SiC substrate is controlled based on difference in a composition of the tantalum silicide layer.

First claim

The invention claimed is:

1. An etching method for etching a SiC substrate that is stored in a storing container, by heating the SiC substrate under Si vapor pressure, wherein
the storing container is formed of a tantalum metal, and a tantalum carbide layer is provided on an internal space side of the tantalum metal, and a tantalum silicide layer is provided on the side further toward the internal space side than the tantalum carbide layer, and
the rate of etching of the SiC substrate is controlled based on a difference of a ratio of the amount of tantalum substance that is contained in the compound for forming the tantalum silicide layer,
wherein at least two storing containers in which compositions of the tantalum silicide layer are different from each other are used depending on performed processes,
wherein a high rate etching and low rate etching can be performed,
in the high rate etching, a storing container having a higher ratio of tantalum occupied in one molecule of a compound for forming the tantalum silicide layer is used, and
in the low rate etching, a storing container having a lower ratio of tantalum occupied in one molecule of the compound for forming the tantalum silicide layer is used.

2. The etching method of the SiC substrate according to claim 1 , wherein
the tantalum silicide layer includes any one of TaSi 2 , Ta 5 Si 3 , Ta 2 Si, Ta 3 Si, and Ta 5 Si 3 C 0.5 .

Assignees

• Toyo Tanso Co
• Kwansei Gakuin Educational Found

Inventors

• Torimi Satoshi
• Shinohara Masato
• Teramoto Youji
• Yabuki Norihito
• Nogami Satoru
• Kaneko Tadaaki
• Ashida Koji
• Kutsuma Yasunori

Classifications

• H10P72/0418

  for etching · CPC title

• H10P50/00

  Etching of wafers, substrates or parts of devices · CPC title

• H10P50/642 Primary

  Chemical etching · CPC title

• C30B35/002

  Crucibles or containers · CPC title

• C30B33/12

  in gas atmosphere or plasma · CPC title