Micropower devices for integrated circuits

This paper describes the development of devices necessary for the design of micropower integrated circuits. These devices were used specifically for complementary micropower (250 micro-watts) NAND and NOR gates and a flip-flop (300 microwatts). NPN and PNP transistors, multiemitter gating transistors, high sheet resistors and high Q capacitors are discussed. Complementary PNP and NPN structures are described as output devices and a multi-emitter device is described for input purposes. By utilizing a separate resistor diffusion, a high temperature coefficient resulted and was used to advantage for compensation of changes in VBEand hFEwith temperature. The high resistivity (500 Ω/□) of the resistor diffusion enabled the actual bar size to be held to a minimum. High Q capacitors were developed using diffused junction techniques that allowed the resistance of the charging path to be decreased. Two methods were incorporated in minimizing inverse alpha of the multi-emitter gating transistor to decrease power drain.