EPITAXIAL YBA2CU3O7-Y BOLOMETERS ON MICROMACHINED WINDOWS IN SILICON-WAFERS

Epitaxial YBCO thin-film bolometers have been successfully fabricated on thin Si(100) substrates. Substrates included prethinned wafers rang ing from 400 mum down to 4 mum thick, and a window, 0.75 mum thick, mi cromachined into a 400-mum wafer. As the Si is made thinner, the speed and responsivity both improve considerably. A 500-mus rise time was a chieved on the micromachined window bolometer (0.75-mum-thick Si) unde r chopped infrared illumination. Calculations of heat flow in Si windo ws are in excellent agreement with the observed window-bolometer respo nse waveform.