Chapter 49 - Micro mirrors

Micro mirrors are widely used in projection displays, retinal scanning displays, in adaptive optics for wavefront correction, in lithography, and many more. Applications such as automotive light detection and ranging (LiDAR), laser marking, or holography are currently further developed based on sophisticated micro scanning mirrors and micro mirror arrays, respectively. A typical bulk micromachining process for fabrication of micro scanning mirrors is described in detail. Design space and typical properties of the devices are discussed. System integration is exemplarily presented by means of a LiDAR module. For fabrication of analog micro mirror arrays, details of a surface micromachining process integrating micro electro mechanical system (MEMS) on complementary metal-oxide-semiconductor (CMOS) are given. Specific requirements for mirror operation as well as results of the optical characterization are discussed. System integration of the arrays is exemplarily described for two selected applications: wavefront correction and microlithography.