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:
Feb. 16, 1993
Filed:
Sep. 30, 1991
Rafael C Alfaro, The Colony, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
An apparatus (10) and method is provided for bonding wire (12) to the bond sites (28) of integrated circuits. In preferred embodiments gold wire (12) is bonded to aluminum bond pad (28). Apparatus (10) includes a high frequency ultrasonic energy source (20) designed to provide ultrasonic energy at frequencies above about 100 kHz causing the interface temperature required for adequate bonding to be greatly reduced. Heating element (19) applies thermal energy to interface (32) via capillary (16) and transducer (18). Therefore, according to the invention, less thermal energy is required from heater block (22) which is heating interface (32) via IC (14) and leadframe (15). In this fashion, leadframe (15) is maintained at a lesser temperature than in the prior art. Since leadframe (15) is at a lesser temperature, it can be plated with a material having a lower melting point (e.g. tin or solder). In preferred embodiments, leadframe (15) is substantially plated with tin (melting point 185.degree. C.) and maintained at about 165.degree. C. Interface (32) is maintained at about 180.degree. C. by thermal energy from heating element (19) (during the bonding process). In preferred embodiments capillary (16) is substantially made of beryllium oxide for adequate thermal conductivity.