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:
Jan. 08, 1980
Filed:
Dec. 15, 1977
Applicant:
Inventor:
Robert A Cometta, San Jose, CA (US);
Assignee:
National Semiconductor Corporation, Santa Clara, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B01J / ;
U.S. Cl.
CPC ...
29571 ; 29574 ; 2957 / ; 29584 ;
Abstract
In a monolithic integrated circuit having a combination of bipolar and junction field effect transistors, a pulsed laser is employed to trim the transistors to achieve balanced circuit performance. The laser is applied to individual circuits in wafer form using a step and repeat operation. Each circuit is measured, the transistor to be trimmed determined and a first trim performed. The circuit is remeasured and, if still out of specification, retrimmed. The process is repeated until a desired degree of balance is achieved.