Optimization of shallow and deep trench isolation structures for ultra-high-speed bipolar LSIs

The authors report on an investigation into the optimization of shallow and deep trench isolation structures for ultra-high-speed bipolar LSIs. Several processes and filling materials were compared in terms of process cost, filling completeness, flatness of the field surface, residual mechanical stress, trench capacitance, etc. Among several candidate fabrication methods, shallow and deep trench isolation structures filled using low-temperature SiO/sub 2/ deposition were the most suitable candidate for ultra-high-speed bipolar LSIs.<>