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. 30, 2005
Filed:
Nov. 26, 2002
Dirk Wollstein, Dresden, DE;
Stefan Lingel, Dresden, DE;
Jan Räbiger, Dresden, DE;
Advanced Micro Devices, Inc., Austin, TX (US);
Abstract
An improved CMP controller allows the calculation of the polish time required for removing a patterned layer stack to a desired final thickness, wherein the initial layer thickness of each layer contained in the layer stack is employed. Moreover, a topography factor characterizing the surface structure of the layer stack and a selectivity characterizing the ratio of removal rates between adjacent material layers are used. Furthermore, a state variable of the controller represented by the removal rate of one of the layers may periodically be updated on the basis of the previously calculated polish time and a measurement value of the finally obtained layer thickness. The improved controller is particularly advantageous in the CMP process for STI isolation structures, in which the final thickness of a CMP stop layer, having a significantly reduced removal rate compared to the overlying dielectric layer, has to be precisely controlled.