Study of the Fabrication Process for a Dual Mass Tuning Fork Gyro

The fabrication process of a dual mass tuning for gyroscope presents many different challenges: the aspect ratio of the sidewalls, the Aspect Ratio Dependent Etch (ARDE) which causes different gaps to be etched in different etching time [1] , the stiction during the release of the free structures, the notching effect that occurs with a dielectric etch stop layer [2] , the thermal contact during the etch process. In this paper are presented different processes and studies of the etching characteristics in order to avoid or minimize these problems.