No abstract

The nonlinear vibration behavior of drivin g mode of a tunnelin g g yroscope is measured and simulated. Based upon these testin g results, a new method for frequency matchin g is presented. Compared to traditional harmonic vibration, lar g e amplitude and wide shift resonance frequency could be obtained in stable re g ion of nonlinearity by usin g this approach, especially, in this re g ion g yroscope could spontaneously vibrate at a certain driven frequency without needin g sweep-up frequency excitation.In our tunnelin g g yroscope, the vibration amplitude changes from l�m to 5�m at jumpin g -up point J I with the amplitude of the excitation electrostatic force increasin g . At the same time, the resonant frequency of drivin g mode can be shifted from nature frequency 1.81 kHz to 2.2 kHz, which is much closed to the resonant frequency of sensin g mode (2.23 kHz). This effect can be used as an alternative approach to trim the frequency and eliminate the frequency mismatchin g for the post-fabrication tunnelin g g yroscope, eventually, hi g her sensitivity could be g otten than usin g linear drivin g mode.

A comparison of glass etching properties between HCI and H�03 solution is presented in this paper, which allows us t� predlc� . the etched product's shape under a variety of etchmg conditIOns, -:nask compensation and multiple processing st�ps. Four conclusIOns could be draw from the experiments. First, the best concentration ratio of the etching solution to prot�ct the mask from damage and get a channel with depth of 40 J.Lm IS HF:HCI:NH4F=5.5moI/L:4moI/L:2.5mol/L. Second, as the temperature increases, the longitudinal etching rate increases.However, the temperature has little influence on the lateral erosion ratio when the temperature gets high. Third, HCI has a better surface morphology against HN03 as an addition to solution. Last, the mask will introduce strain because of sputtering, which is harmful to the glass etching ..