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:
Apr. 18, 2006
Filed:
May. 13, 2003
Philbert Francis Marsh, Andover, MA (US);
Colin Steven Whelan, Wakefield, MA (US);
Philbert Francis Marsh, Andover, MA (US);
Colin Steven Whelan, Wakefield, MA (US);
Raytheon Company, Waltham, MA (US);
Abstract
A method for passivating a photodiode so as to reduce dark current, I, due to the exposed semiconductor material on the sidewall of the device. The method includes etching away sidewall surface damage using a succinic acid-hydrogen peroxide based sidewall etch. This is followed by a subsequent hydrochloric acid (HCl)-based surface treatment which completes the surface treatment and reduces the dark current I. Finally, a polymer coating of benzocyclobutene (BCB) is applied after the surface treatment to stabilize the surface and prevent oxidation and contamination which would otherwise raise the dark current were the diodes left with no coating. The BCB is then etched away from the contact pad areas to allow wirebonding and other forms of electrical contact to the diodes. Such method effectively stabilizes the etched surfaces of photodiodes resulting in significantly reduced and stable dark current.