This chapter introduces several fabrication technologies, including different complementary metal oxide semiconductor (CMOS) and post-CMOS processes, to implement CMOS micro-electro mechanical systems (MEMS) devices. It provides the post-CMOS process modules to define multilayer thin films of back end of line and to remove the silicon substrate. The post-CMOS technology has been implemented for many years to attain monolithic integration with the IC technology and avoid thermal budget limitation simultaneously. The chapter explains a few sensors and devices such as resonators, accelerometers, and pressure sensors to show the integration of different post-CMOS process modules to implement MEMS devices on the wafer prepared by the standard 2P4M CMOS platform. It explores the operating concepts and fabrication principles of tactile sensors, infrared sensors, and resonators based on 1P6M CMOS technology where the process modules. It demonstrates the monolithic integration of multiple sensors and sensing circuits to exhibit the capability of CMOS MEMS for the realization of sensing hubs.