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. 19, 1995
Filed:
Jan. 31, 1994
Gregory N Burton, Belmont, CA (US);
Chen-Hsi Lin, Cupertino, CA (US);
Chi-Kwan Lau, Saratoga, CA (US);
Other;
Abstract
The present invention provides a buried layer fabrication sequence suitable for bipolar and BiCMOS applications. The buried layer fabrication sequence for forming a buried layer having a first conductivity type includes the steps of: forming a first dielectric layer on a semiconductor substrate, the semiconductor substrate having a second conductivity type; forming a first mask layer having openings on top of the first dielectric layer, wherein the openings in the first mask layer are positioned over the regions where the first buried layer is formed; exposing the semiconductor substrate in the regions where openings in the first mask layer are formed; forming a second dielectric layer; removing the second dielectric layer; and forming a semiconductor layer.