1. A bimorph thermal actuator is given below. Silicon dioxide and crystalline silicon have a thermal expansion coefficient of 0.35 106 / K and 2.6 10-6 / K, respectively. Silicon dioxide and crystalline silicon have a Young's modulus of 130 GPa and 70 GPa, respectively. For the silicon dioxide layer, t2 = 1 um, b2 = 20 um, and 12 = 200 um. For the crystalline silicon layer, b1 = 25 um and 11 = 200 um. This cantilever uses an integrated metal thin-film heater to increase the cantilever temperature by 100 K. The heater is not shown on the top surface of the cantilever, because the metal film is negligibly thin. To obtain a displacement of 3 um at the free end of the cantilever, find the thickness of the crystalline silicon layer (t1) for the cantilever. Also, design and describe a fabrication process for manufacturing this cantilever. Silicon dioxide t Crystalline b silicon