Laser bending of silicon'

摘要

We are going to present a new technology for laser machining of silicon developed at the Laser Institute of Mittweida by a suggestion and in cooperation with the Technical University of Chemnitz, Department of Electrical Engineering and Information Technology. It allows the laser induced bending of microstructural silicon elements prepared by anisot-ropic wet etching. Bending of the element toward the incident laser beam occurs as a result of the laser induced thermal stresses in the material. We investigated the influence of various process parameters on the bending angle. There is only a small range of laser power to generate bendings in silicon. We will show a variety of examples including multiple and also continuous bend-ings. There are several essential advantages compared to conventional bending technologies: Laser bending is a contactless process without using additional tools or external forces. Because of the local laser treatment the heat flux to neighbouring material can be minimized so that the technology is suitable for machining of already finished microsystems. This new technology opens up a new field of applications in microsystem technologies. It is possible to generate a clip-chip-mechanism to clip a chip in a holder. Other examples are the exact positioning of optical mirrors or other components, the production of electrostatic drives and sliding chips for micro optical benches.