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:
Aug. 16, 1988
Filed:
Jul. 07, 1986
Applicant:
Inventors:
Ronald A Powell, Redwood City, CA (US);
Susan B Felch, Los Altos, CA (US);
Assignee:
Varian Associates, Inc., Palo Alto, CA (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01K / ;
U.S. Cl.
CPC ...
374178 ; 374-7 ;
Abstract
A probe having four spring-loaded tips contacts the backside of a semiconductor wafer in a processing machine. A current is induced across the outer tips and a voltage proportional to the sheet resistance of the wafer is measured across the inner tips. Wafer thickness is used to convert sheet resistance to bulk resistivity. Data on resistivity as a function of temperature is used to determine wafer temperature.