Investigation of Charge Injection and Relaxation in Multilayer Dielectric Stacks for Capacitive RF MEMS Switch Application
Investigation of Charge Injection and Relaxation in Multilayer Dielectric Stacks for Capacitive RF MEMS Switch Application
复制标题
针对电容式 RF MEMS 开关应用的多层电介质堆栈中的电荷注入和弛豫研究
DOI：
10.1109/ted.2013.2263252
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发表时间：
2013-07-01
影响因子：
3.1
通讯作者：
Chen, Xuyuan
中科院分区：
文献类型：
--
作者：
Li, Gang;Zhang, Wendong;Chen, Xuyuan
提出了一种新的解决电容式射频（RF）微机电（MEMS）开关由于介质充电而产生的不可逆粘滞问题的方法。本文研究了采用金属-绝缘体-半导体（MIS）电容器结构的电容式RF MEMS开关的多层和单层介质结构中电荷的积累。采用SiO2+ Si_3N_4和SiO2+ Si_3N_4 + SiO_2两种多层介质膜结构。同时，还制备了Si_3N_4单层介质结构作为对比。在实验中，空间电荷首先注入到介电层通过强调MIS设备与直流偏置，然后注入的电荷动力学监测之前和之后的电容-电压测量。我们发现，在电介质中积累的电荷的极性是强烈的电介质结构的影响。当金属电极被正偏置时，负电荷在单层和三层器件中积累，而正电荷在双层器件中积累。此外，实验结果还表明，尽管三层介质结构的弛豫过程最快，但双层介质结构的电荷积累量最小。
This paper proposes a new approach to the problem of irreversible stiction of capacitive radio frequency (RF) microelectromechanical (MEMS) switch attributed to the dielectric charging. We investigate how charge accumulates in multi- and single-layer dielectric structures for a capacitive RF MEMS switch using metal-insulator-semiconductor (MIS) capacitor structure. Two multidielectric-layers are structured, which are SiO2+Si3N4 and SiO2+Si3N4+SiO2 stack films. Meanwhile, Si3N4 single-layer dielectric structure is also fabricated for comparison. In the experiments, the space charges are first injected into the dielectric layers by stressing MIS devices with a dc bias; then the injected charge kinetics are monitored by capacitance-voltage measurement before and after charge injection. We found that the polarity of charge accumulated in the dielectric is strongly influenced by the dielectric structure. When the metal electrode is positively biased, a negative charge accumulates in the single and triple-layer devices, while a positive charge accumulates in the double-layer devices. Furthermore, the experiment results also show that the lowest charge accumulation can be achieved using double-layer dielectric structure even though the fastest relaxation process takes place in triple-layer dielectric structure.