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:
Nov. 23, 2004
Filed:
Aug. 26, 2003
Takato Handa, Shiga, JP;
Hiroyuki Umimoto, Hyogo, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A hard mask which has an opening for exposing a p-type region defined in a silicon substrate and is made of, for example, a BPSG film is formed. Then, the hard mask is subjected to isotropic etching using argon gas, to have its edge rounded off, thereby forming an implantation hard mask having a tapered edge. Subsequently, large-angle-tilt ion implantation of an n-type impurity is performed using the implantation hard mask as a mask, thereby forming an n layer having an LDD structure. Thereafter, the implantation hard mask is removed. In this manner, it is possible to perform large-angle-tilt ion implantation using an implantation mask thinner than a conventional implantation mask.