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:
Nov. 25, 2008
Filed:
Jul. 26, 2004
Rajneesh Jaiswal, Tucson, AZ (US);
Eric W. Beach, Tucson, AZ (US);
Barbara M. Barnes, Tucson, AZ (US);
Rajneesh Jaiswal, Tucson, AZ (US);
Eric W. Beach, Tucson, AZ (US);
Barbara M. Barnes, Tucson, AZ (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A method of determining the degree of calibration of an RTP chamber () includes providing a test wafer having a deposited sichrome layer () of sheet resistance Rsi on an oxide layer () formed on a silicon substrate (). The test wafer is annealed in the RTP chamber for a selected duration at a selected anneal temperature which is measured by the a permanent thermocouple or pyrometer (). The sheet resistance of the annealed sichrome is measured, and a sheet resistance change ΔRs=Rsi−Rsf is computed. The 'actual' value of the anneal temperature is determined from predetermined characterizing information relating ΔRs to a range of values of anneal temperature. The RTP chamber is re-calibrated if in accordance with the value of ΔRs if the difference between the 'actual' value of the anneal temperature and the value measured by the permanent thermocouple or pyrometer exceeds an acceptable error. The basic technique can be utilized to determine an anneal time and anneal duration for annealing sichrome resistors to precisely adjust the sheet resistance or TCR thereof.