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:
Mar. 22, 1988
Filed:
Mar. 17, 1987
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method of automatically forming identically positioned alignment marks on the front side and the back side of a silicon wafer especially prepared for use in silicon micromechanical technology. The front side and the back side of the silicon wafer are coated with an insulating layer. High-energy heavy ions are directed onto the front side insulating layer. The heavy ions penetrate the front side insulating layer, the wafer, and the back side insulating layer, thus forming single disturbed crystal lattice nuclear tracks in both insulating layers, with the wafer remaining undisturbed. The nuclear tracks in both insulating layers are etched so that corresponding identically positioned pores are opened. These pores are used as alignment marks for individual further method steps.