SEMICONDUCTOR MEASUREMENT TECHNOLOGY: MICROELECTRONIC ULTRASONIC BONDING.

This report consists primarily of excerpts of the work done under the NBS ultrasonic wire bonding program that was previously published in 17 quarterly and other reports. The material is organized into subject groupings with the intention of presenting in convenient form sufficient information for making high quality ultrasonic wire bonds as well as imparting a basic understanding of the ultrasonic systems used. The work emphasizes problems and methods of solving them. To accomplish this, the required measurement equipment is first introduced. This is followed by procedures and techniques used in setting up a bonding machine, and then various machine- or operator-induced reliability problems are discussed. The characterization of the ultrasonic system and its problems are followed by in-process bonding studies and work on the ultrasonic bonding (welding) mechanism. The report concludes with a discussion of various effects of bond geometry and wire metallurgical characteristics. Where appropriate, the latest, most accurate value of a particular measurement has been substituted for an earlier reported one. Thus all of the included material is up to date.