The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 06, 2016
Filed:
Sep. 26, 2013
Shin-etsu Handotai Co., Ltd., Tokyo, JP;
Takeshi Arai, Fukushima, JP;
Satoshi Inada, Fukushima, JP;
SHIN-ETSU HANDOTAI CO., LTD., Tokyo, JP;
Abstract
Carry out a vapor etching step of cleaning an inside of a chamber of a vapor phase growth apparatus by vapor etching using HCl gas (S). Carry out an annealing step of sequentially annealing a predetermined number of silicon wafers, one by one, in a non-oxidizing atmosphere (S, S). Repeat the vapor etching step and the annealing step a prescribed number of times. After having carried out the vapor etching step and the annealing step the prescribed number of times (S: Yes), collect contaminants on the surface of each of the wafers, and measure the Mo concentration using ICP-MS (S). Evaluate the cleanliness of the vapor phase growth apparatus on the basis of each Mo concentration value and the relationship between the Mo concentrations (S). Thus, provided is a method with which it is possible to measure, with high sensitivity, the contamination amount of a vapor phase growth apparatus.