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:
Dec. 26, 1989
Filed:
Dec. 23, 1987
Pallab K Chatterjee, Dallas, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A process for forming backside contacts includes first forming an etch stop layer (12) beneath the surface of a silicon substrate. An active circuit is then formed in the silicon surface and associated metal interconnecting layers formed on the upper surface of the substrate. A planarizing layer is then formed on the upper surface of the substrate which is operable to be connected to a mechanical support. Thereafter, the backside of the substrate is etched away up to the etch stop layer (12). The thickness of the remaining substrate between the metal layers on the upper surface and the etch stop layer is sufficiently thin that the alignment marks on the upper surface can be seen through the substrate. These alignment marks are utilized to form vias from the backside to the active elements and then deposit and pattern interconnecting layers on the backside.