Trends in x-ray lithography

Abstract

Presently there are several approaches to achieving a high throughput, production worthy X-ray lithography system. One approach utilizes a conventional X-ray source with fast X-ray resist materials to expose a large diameter wafer (typically 3” to 4” in one step). Another approach also utilizes a conventional X-ray source (or perhaps a plasma X-ray source) and fast X-ray resist materials to expose in a step and repeat fashion a large diameter wafer (e. g., ≤5M). A third approach utilizes a storage ring source of X-ray radiation in combination with conventional resist materials (i. e., AZ, PMMA, etc.) to expose large diameter wafers in a step and repeat fashion. In particular, single step exposure systems are limited to small diameter wafers due to registration errors which are ameliorated in step and repeat systems. Furthermore, the complex multilevel resist processing necessary to obtain high throughput in the first two approaches is unattractive to some manufacturers. However, it may be one economic way of obtaining relatively high throughput for some applications that require a small volume of devices with ≤1μm features. For high volume manufacturers with well established production lines using conventional resist processing, a multiple port storage ring system offers economical and performance advantages relative to other exposure systems (i. e., electron beam) for VLSI manufacturing. The important parameters of each fo the above approaches will be described in this talk. © 1982, SPIE.