• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 G
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• pp.2518-2520
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• 1998

Silicon can be reactive ion etched (RIE) either isotropically or anisotropically. In this paper, a new micromachining technology combining these two etching characteristics is proposed. In the proposed method, the fabrication steps are as follows. First. a polysilicon layer, which is used as the bottom electrode, is deposited on the silicon wafer and patterned. Then the silicon substrate is etched anisotropically to a few micrometer depth that forms a cavity. Then an PECVD oxide layer is deposited to passivate the cavity side walls. The oxide layers at the top and bottom faces are removed while the passivation layers of the side walls are left. Then the substrate is etched again but in an isotropic etch condition to form a round trench with a larger radius than the anisotropic cavity. Then a sacrificial PECVD oxide layer is deposited and patterned. Then a polysilicon structural layer is deposited and patterned. This polysilicon layer forms a pivot structure of a rocker-arm. Finally, oxide sacrificial layers are etched away. This new micromachining technology is quite simpler than conventional method to fabricate joint structures, and the devices that are fabricated using this technology do not require a flexing structure for motion.