A perspective on SOI symmetric lateral bipolar transistors for ultra-low-power systems

Abstract

The reasons why state-of-the-art vertical bipolar circuits dissipate very high power are explained. The recent advent of SOI symmetric lateral bipolar transistors invites us to rethink bipolar as a high-speed but low-power technology. Integrated Injection Logic (I2L) and complementary bipolar (analogous to CMOS) circuits in SOI lateral bipolar offer huge design windows for power versus performance tradeoff, suggesting the possibility of ultra-low-power systems with embedded high-speed cores. I2L SRAM cells could be more than twice as dense as CMOS SRAM cells. The SOI substrate offers a fourth device terminal that can be used to induce narrow-gap-base HBT-like I-V characteristics, which should further improve the power-performance of circuits in SOI lateral bipolar. Fin-structure devices enable significant improvement in fmax for RF and high-frequency applications. The process technology for SOI lateral bipolar is compatible with CMOS. The Si-OI version is definitely much less complex than CMOS.