Triple-sided charged plasma symmetric lateral bipolar transistor on SiGe-OI

Abstract

A novel triple sided charged plasma (3SCP) device structure of a symmetric lateral bipolar transistor (SLBT) on silicon–germanium on insulator (SiGe-OI) is proposed. Charged plasma lateral bipolar transistor on SOI have many advantages especially in overcoming the thermal budget in addition to high gain and high speed for analog signal applications. In this paper we have carried out a systematic study of this novel 3SCP SLBT with uniform 0.3 Ge content in silicon and with linearly graded SiGe as the active device layer. With 3SCP SLBT having linearly graded SiGe as active device layer we were able to achieve a current gain > 104, fT > 200 GHz and fmax > 1130 GHz. We were able to demonstrate improvement in terms of current gain, fT and fmax by around 4.52, 2.55 and 2.07 times respectively with our novel design as compared to the conventional charged plasma symmetric lateral bipolar transistor (CP SLBT) having uniform 0.3Ge content in Silicon as active device layer. A complementary 3SCP symmetric lateral bipolar inverter with linearly graded SiGe as active device layer is also discussed for digital applications. The inverter shows switching voltage (VM) = 0.4616 V, low noise margin (NML) = 0.4302 V and high noise margin (NMH) = 0.4725 V when operated at 1.0 V.