Low-power SITL IC

The SITL (static induction transistor logic), which operates in the bipolar mode, has the smallest PD (power delay) product in silicon technology because of the use of an extremely pure epitaxial layer. In this paper, as SITL device is which the gate and drain are self-aligned is described, centering on the DC characteristics and operation limit. It is concluded that the drain current of SIT is limited by the thermionic emission mode in a low-current region of about 1 nA over a wide temperature range, and that logic operation is limited by the effective current gain β/SUB eff/ in the low-power region. Designing SITL suitably for wide temperature and power range, the authors have developed a monolithic watch IC having an oscillation frequency of 2 MHz and a current consumption of 3.5 μA, and including bipolar circuitry on the same chip.