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:
Jul. 11, 1989
Filed:
Aug. 05, 1988
Bor-Yuan Hwang, Chandler, AZ (US);
Carroll M Casteel, Mesa, AZ (US);
Sal T Mastroianni, Tempe, AZ (US);
Motorola Inc., Schaumburg, IL (US);
Abstract
An improved means and method for forming an optical sensor within an integrated circuit structure is described. An epi-coated semiconductor wafer is masked and a cavity etched through the epi-layer to the underlying substrate. A dielectric sidewall is formed on the cavity sidewall and a substantially intrinsic semiconductor region, preferably grown by selective epitaxy, to refill the cavity. The upper surface of the intrinsic region is then heavily doped and contacted by a low resistance polysilicon layer which is substantially transparent to incoming light. The method forms a high sensitivity PIN photo-sensor having a thick space-charge region for efficient capture of the hole-electron pairs produced by the incoming light. The fabrication techniques are compatible with the processing requirements for other integrated circuit devices formed on the same chip and to which the PIN device is coupled without wire bonds, tabs, bumps or the like.