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:
Sep. 28, 2004
Filed:
Feb. 21, 2003
Newport Fab, LLC, Newport Beach, CA (US);
Abstract
According to one exemplary embodiment, a method for fabricating a bipolar transistor in a BiCMOS process comprises a step of forming an emitter window stack by sequentially depositing a base oxide layer and an antireflective coating layer on a top surface of a base, where the emitter window stack does not comprise a polysilicon layer. The method further comprises etching an emitter window opening in the emitter window stack. The method further comprises depositing an emitter layer in the emitter window opening and over the antireflective coating layer and etching the emitter layer to form an emitter. The method further comprises etching a first portion of the base oxide layer not covered by the emitter using a first etchant, thereby causing the first portion of the base oxide layer to have a thickness less than a thickness of a second portion of the base oxide layer covered by the emitter.