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:
Jul. 06, 1993
Filed:
Jun. 04, 1991
Richard A Elder, Dallas, TX (US);
Arthur M Wilson, Dallas, TX (US);
Susan V Bagen, Dallas, TX (US);
Juanita G Miller, Richardson, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A flexible polyimide film is used to support an array of precisely located contact bumps which are used to probe die on a wafer of semiconductor circuits, or an unmounted integrated circuit die, several integrated circuits, or hybrid devices. By utilizing a standard I/O contact pattern for the flexible film and fabricating the membrane assembly of interconnects on an aluminum substrate, it is possible to produce a more reliable probe card, while reducing the fabrication time and costs for the probe card. The polyimide film must be selected to have a CTE of 3 to 5, which is only about 1/5 to 1/7 as great as the CTE of the aluminum substrate on which the film is formed. This produces a critical degree of compressive stress in the polyimide film, and a resulting 'bow' of the film when the central area of the aluminum is etched away.