三极板型RFMEMS压控电容的分析与制作

Analysis and Fabrication of Three Electrode Pair MEMS Voltage Controlled Capacitor

设计并制作了基于硅基的射频微机械压控电容。该电容采用三对极板的传动结构,当两侧控制极板受到静电力驱动时,位于中部的电容极板将得到更大的位移。能量分析和软件模拟表明,该结构有助于提高压控电容的变化比例。测量表明,该电容品质因数为17@2GHz,并具有较大的电容变化比例(大于50%)。该电容工艺简单,实现温度较低(小于350℃),具有与CMOS工艺集成的可行性。

The analysis and fabrication of a MEMS based voltage controlled capacitor (VCC) is reported.The capacitor structure includes three electrode pairs.When voltage is applied to the two control electrode pairs at the wing,the upper plates will be pulled down by electrostatic potential,and the central capacitor plate will fall down through more distance.Energy method and software analysis are used to analyze the performance of the device and the advantage is confirmed.The device has quality factor of 17@2GHz and tuning range more than 50%.A low temperature (less than 350℃) surface micromachining is used for the fabrication in order to assure the compatibility with CMOS processes.