Hexsil Bimorphs For Vertical Actuation

Three designs are demonstrated for molded structures that move vertically upon HF etch release. Deflection is due to differences in residual stress in two or more deposited films. Displacements of 700 /spl mu/m to 1.1 mm occurred in 9 mm long, 30 /spl mu/m high molded polysilicon cantilevers. A 4 level tower 8 x 8 mm square rose 840 /spl mu/m. Lifters patterned 400 /spl mu/m wide in surface films rose 35 to 45 /spl mu/m. Hexsil test structures were also made to measure a lower bound for the ultimate strength in compression (> 206 MPa) and in tension (> 128 MPa).