ADVANCED METAL-OXIDE SEMICONDUCTOR AND BIPOLAR-DEVICES ON BONDED SILICON-ON-INSULATORS

Silicon-on-insulator devices have problems with both performance and cost. We developed three advanced devices on bonded SOI produced using pulse-field-assisted bonding and selective polishing in an attempt to solve these problems. We tightly bonded highly implanted wafers, epitaxial wafers, and wafers covered with smoothed CVD oxide at temperatures below 1000-degrees-C. We uniformly thinned bonded wafers by grinding, polishing, resistivity-sensitive etching, or selective polishing. We formed buried layers and buried electrodes by bonding and polishing techniques. Our high speed epitaxial-base transistor on 1-mum thick SOI has a cutoff frequency of 32 GHz. Our lateral bipolar transistor with a thin base on 0.15-mum thick SOI had a cutoff frequency of 4 GHz. A double-gate MOSFET on 60-ran thick SOI had a transconductance of more than twice that of a conventional SOI MOSFET This paper discusses further advantages of bonded SOI techniques.