Thin-film processes for microelectronic application

The rapid development of the microelectronics industry over the last decade has placed exceptional demands on thin-film technology since, to a large extent, it controls the technological pace of that industry. This demand has challenged the thin-film technologist to develop new and improved processes for both thin-film devices as well as for the thin-film conductors and insulation needed by semiconductor devices. The projected demands of the coming decade will require advances in the technology comparable to those of the past decade if the full potential of large scale integration is to be achieved. The variety of materials and processes required to meet adequately the total needs of the industry has necessitated the development of several deposition technologies. Vacuum evaporation, sputtering, chemical vapor deposition, sedimentation, etc., are all in volume manufacturing use and the technologies of each of these techniques has been significantly improved during the past ten years. A similar increase in process capability and control has been necessary in the area of pattern definition in order to allow the development of fine line etching which achieves the required narrow linewidths and separations in today's microelectronic assemblies. The materials of major interest to the industry as well as the deposition techniques and photoengraving processes used in their processing are highlighted. The discussion includes the status and limitations of the technology as it exists today as well as a consideration of the advantages and disadvantages of the various processes both as of today and for the future.