Semiconductor device having an enlarged space area surrounding an isolation trench for reducing thermal resistance and improving heat dissipation

Abstract

A semiconductor device includes a lower substrate, a thin semiconductor layer and an insulating layer formed between the lower substrate and the semiconductor layer. An active transistor area is formed with a base formed along a surface of the semiconductor layer, an emitter region formed in the base, a buried collector in the thin semiconductor layer to contact the insulating layer, a collector contacting the buried collector, and emitter, collector and base contacts. The active transistor area is configured to operate at an emitter current at least in the order of mA (milli-ampere). An isolation trench extends through the semiconductor layer to the insulating layer and surrounds the active transistor area with a distance in the order of μm (micron) from the active transistor area and with a space area of more than 50 μmbetween the active transistor area and the isolation trench.