On the design and fabrication of novel lateral bipolar transistor in a deep-submicron technology

The performance of a npn Lateral Bipolar Transistor (LBJT), based on a mini mally modified submicron MOSFET without gate oxide, was studied by means of simulations and measurements on fabricated devices. Large-tilt angle, sing le-sided implants were successfully used to control the breakdown voltage b y tailoring an asymmetric collector doping profile and providing a lightly doped region on the collector side to increase the breakdown voltage. This was accomplished by using a base/gate pedestal as the mask for the large-ti lt angle, single sided implantation in a self-aligned fashion. The individu al collector-base and emitter-base junctions were found to be of excellent quality but, as expected due to the lack of carrier confinement in the base of devices built on bulk silicon, the common emitter current gain was lowe r than one. Two options enhancing the device performance were studied using simulators: building the LBJT on Silicon-on-insulator (SOT) or introducing SiGe into the base. The SOI device promises to provide better performance and ease of processing when compared to the SiGe base device. (C) 2000 Else vier Science Ltd. All rights reserved.