Review of optical direct-write technology for semiconductor manufacturing

Optical direct-write technology has been studied since the successful development of the micromirror-based spatial light modulators in the 1990s. It is expected to have advantages over electron beam direct-write in the viewpoints of higher productivity and common resist process with existing semiconductor manufacturing. In the 2000s, there was an effort to develop an optical direct-write system using deep ultraviolet (DUV) excimer laser and grayscale tilt micromirror devices, aiming at low-volume manufacturing of semiconductor devices. Recently, a new scheme of optical direct-write, called the digital scanner, has been demonstrated. It uses solid-state DUV laser and digitally controlled spatial light modulator. Past development activity of optical direct-write is reviewed with discussion of the merits and demerits of the proposed technological options in the new system, comparing them to past efforts.