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:
Jun. 09, 2020
Filed:
Apr. 06, 2018
Jx Nippon Mining & Metals Corporation, Tokyo, JP;
Taku Yoshida, Ibaraki, JP;
Hideki Kurita, Ibaraki, JP;
JX Nippon Mining & Metals Corporation, Tokyo, JP;
Abstract
The present invention provides: an InP wafer optimized from the viewpoint of small edge roll-off (ERO) and sufficiently high flatness even in the vicinity of a wafer edge; and a method for effectively producing the InP wafer. The InP wafer having a roll-off value (ROA) of from −1.0 μm to 1.0 μm is obtained by using a method including: performing a first stage polishing under a processing pressure of from 10 to 200 g/cmfor a processing time of from 0.1 to 5 minutes, while supplying a polishing solution containing bromine to at least one side of an InP single crystal substrate that will form the InP wafer; and performing a second stage polishing under a processing pressure of from 200 to 500 g/cmfor a processing time of from 0.5 to 10 minutes, provided that the processing pressure is higher than that of the first stage polishing by 50 g/cmor higher.