Power integrated circuits-progress, prospects and challenges

PICs (power integrated circuits) are defined as ICs combining high-voltage and/or high-current components monolithically with low-voltage/low-current control components. Broadly, three classes of technologies, based on the techniques for isolating the high- and low-voltage components, have been developed for PICs: junction-isolated, self-isolated and dielectrically isolated. Each of these technologies has found its way into applications that result in optimal performance per unit cost. Simultaneously with the development of technologies, several advancements have been made in high-voltage/power devices suitable for integration. These included the reduced surface field lateral double diffused MOS transistor (RESURF LDMOS), the isolated vertical DMOS (VDMOS), the lateral insulated gate bipolar transistor (LIGBT), the high-voltage RESURF bipolar transistors, the Schottky injection FET (SINFET), and the trench sidewall channel DMOS (TDMOS). Innovative device designs like the LIGBT have resulted in die sizes reduced by a factor of 3 to 5 and therefore in lower cost. In high-current applications, trench-based power devices are being developed for silicon die size reduction by more than a factor of 2. Additionally, with high-density control sections and cell-library-based automated design methods, custom ASIC (application-specific IC) designs are being developed rapidly at lower cost.