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:
Dec. 14, 1999
Filed:
Oct. 04, 1996
Katsunari Hanaoka, Ono, JP;
Ikuo Shiota, Hyogo-ken, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A method for forming ohmic contact has the steps of a) a process for forming an insulating film having a predetermined thickness on a diffusive layer formed on a semiconductor substrate; b) a process for forming a mask on the insulating film; the mask having a small selective ratio with respect to the insulating film and having an opening portion for a contact hole; c) a process for implanting ions into the diffusive layer through the opening portion; d) a process for taking heat treatment to electrically activate the implanted ions; e) a process for completely removing the mask and forming the contact hole by simultaneously etching the mask and the insulating film exposed through the opening portion of the mask; and f) a process for making an electrode come in ohmic contact with the semiconductor substrate exposed from the formed contact hole. In this method, the ohmic contact is formed with high accuracy with respect to a fine contact hole.