Development of fast prototyping laser technique for production of surface acoustic wave gyroscopes

Abstract

Solid-state micromechanical gyroscopes based on surface acoustic waves (SAW) have good vibration and shock resistance because of absence of elastic suspensions, ability to work at 50 000 g loads, small dimensions, cheap in mass production, etc. Unfortunately, there are some limits for further development of such gyroscopes because it requires prototype production in small series. In this study we have investigated laser ablation method to solve this problem. Idea of this method is to evaporate unnecessary metallization from the piezoelectric crystal surface, e.g. to “draw” the electrode topology with a powerful laser beam. Main advantages of the method are as follows: possibility of fast and cheap sensors prototyping even with complicated topologies; reduction of the number of production process stages; possibility of topology correction (especially in case of transparent crystal housing); operation with thicker metal layers then traditional photolithography method, etc.