The first thin-film electronic package

Abstract

The magnetic thin-film head, announced by IBM in 1979, marked the transformation of electrochemical technology from a shop art to a precision manufacturing process with far wider applications than the thin film head. An important application of electroplating was in the fabrication of the multichip module that provided the packaging for chips in advanced computers. These modules included copper strip lines for data transmission between chips. To minimize pulse distortion, these lines had to have precisely controlled propagation characteristics, and plating through a lithographic mask was the most effective way to insure the tight control on the geometry of the lines necessary to meet this requirement. This paper highlights the evolution of packaging for computers and tells how the scientists and engineers from the IBM T.J. Watson Research Center who had created the thin film head, worked with the development and manufacturing groups at IBM's East Fishkill plant to bring electrochemistry into the manufacture of advanced packaging modules.