Post-CMOS and Post-MEMS Compatible Flexible Skin Technologies: A Review

This paper reviews flexible skin technologies that enable monolithic integration of silicon CMOS circuits and high temperature MEMS devices on flexible substrates. The monolithic integration is achieved by fabricating CMOS circuits or MEMS sensors on silicon wafers first and then forming flexible skins by post-processing. In this sense, these flexible skin technologies are termed as post-CMOS and -MEMS compatible. Most flexible devices developed using these technologies share a common structure - silicon islands connected by flexible cables. Representative works in this field are reviewed. Important aspects such as materials, releasing methods, and interconnection methods are discussed. A brief comparison of post-CMOS and -MEMS compatible flexible skin technologies with other technologies is presented.