Abstract
This thesis is dedicated to the study of PECVD low stress films and ultra-thick sacrificial layers. By doping and adjusting the PECVD parameters such as power, temperature, pressure and the ratio of reactive gas, it can reduce the stress of the deposited films and flat cantilever beams can be fabricated. The optimum process parameters for low stress and high etching rate thick sacrificial layers of 5μm and more are obtained. Using this thick low stress sacrificial layer suspended micro-structures are easily fabricated by surface micromaching technology.