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:
Apr. 11, 1989
Filed:
Apr. 24, 1987
William H Arnold, III, Cupertino, CA (US);
Mohammad Farnaam, Santa Clara, CA (US);
Jack Sliwa, Los Altos Hills, CA (US);
Advanced Micro Devices, Inc., Sunnyvale, CA (US);
Abstract
Reflection of incident optical radiation (18) from a highly reflective metal layer (12), such as aluminum or titanium, into a photoresist layer (14) is reduced by interposing a layer of titanium nitride (16) between the metal and photoresist layers. The thickness of the TiN layer depends on the wavelength of the optical radiation used to expose the photoresist and on the optical properties of the underlying metal layer. Reflectance of less than about 2% may be achieved using the TiN layer in conjunction with aluminum and less than about 5% in conjunction with titanium, in accordance with the invention. If left in place after patterning an underlying aluminum layer, the TiN layer also serves to suppress hillock formation in the aluminum layer.