IC-Compatible Polysilicon Surface Micromachining

TLDR

Polysilicon surface micromachining is rapidly advancing beyond prototyping, with growing interest in optical, wireless, sensor, and other applications. The study aims to develop IC‑compatible materials that improve microsystem performance, reliability, and harsh‑environment operation. By integrating IC fabrication techniques such as chemical‑mechanical polishing planarization, the authors extended the process to a five‑level technology. The five‑level process expands design space for microactuators, and in‑situ microdiagnostics have deepened reliability insights, enabling devices to approach material limits.

Abstract

▪ Abstract Polysilicon surface micromachining is advancing significantly and many new applications are moving beyond the prototyping phase. Recent technical successes are leading to excitement concerning various uses of devices in optical, wireless, sensor, and many other areas. Incorporation of state-of-the-art integrated circuit (IC) fabrication methods, such as planarization by chemical mechanical polishing (CMP), has enabled extension to a five-level technology. This has opened significant design space, especially for microactuator applications. Recent advancement of in situ microdiagnostics for materials and surface properties has enhanced our understanding of device reliability and performance and will allow devices to operate near well-known materials limits. New IC-compatible materials will further enhance the capabilities of microsystems in terms of performance, reliability, and operation in harsh environments.