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. 13, 1987
Filed:
May. 21, 1984
Allan Rosencwaig, Danville, CA (US);
Walter L Smith, Livermore, CA (US);
Therma-Wave, Inc., Fremont, CA (US);
Abstract
An apparatus and method is disclosed for evaluating surface conditions on a sample. The system is particularly suited for detecting thin residues encountered in semiconductor lithographic and etching processes. The system is also capable of measuring ion implanted dopant concentrations prior to annealing. The apparatus includes an intensity modulated laser beam which is focused on the surface of the sample to generate periodic heating. A second light beam is focused onto the periodically heated area of the sample in a manner such that it is reflected to a detector. The intensity changes in the probe beam, resulting from the temperature induced changes of reflectivity at the surface of the sample, are measured and evaluated to determine the absence or presence of residues, or to measure the concentrations of ion implanted dopants.