Micromachined electrical switches with bi-stable springs, which can stay at one of the two stable states without consuming energy, are proposed. Cascaded bent beams are incorporated as thermoelastic microactuators and are characterized through a coupled electro-thermo-mechanical analysis using ANSYS. For improved electrical switch performance, the contact resistances should be kept as low as possible. Therefore, the shape of the contact head needs to be optimized, though to date there have been few studies pertaining to the contact heads of electrical switches reported, except for a flat contact shape. In this paper, the effects of contact angle on the electrical resistance are investigated for contact angles of 30°, 45°, and 60°. It is subsequently observed that the contact resistance decreases with the contact angle due to a greater normal contact force; the minimum contact resistance is 0.22 Ω at a contact angle of 60°. The contact resistance shows negligible change during repeated ON/OFF switching operations.
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