Device simulation study of lateral Schottky collector phototransistor (SCPT)
Date of Issue2009
School of Electrical and Electronic Engineering
This report documents the device simulation study of lateral Schottky Collector Phototransistor (SCPT). In silicon-on-insulator (SOI) waveguide-based photodetector, Schottky-barrier Photodiode (SPD) owns some advantages over the Ge-photodetector, such as longer cut-off wavelength, ease fabrication, low cost, and smaller size etc. However, it suffers low responsivity due to low quantum efficiency. The novel lateral SCPT proposed by IME improved the responsivity by amplifying the primary photocurrent through transistor action. The proposed lateral SCPT differs from the NPN phototransistor in that the collector-base junction consists of a Schottky junction between the metal (M) and/ p-base (P). The characteristics of the lateral SCPT were explored using two-dimensional simulation with Medici. Due to relatively long base width (2.4μm), the proposed SCPT only achieves a current gain of 9.9. By simulating the forward current characteristics for different combinations of base width and emitter doping, the current gain can be improved to 49.7 for a narrower base width (0.8μm).
DRNTU::Engineering::Electrical and electronic engineering::Semiconductors
Final Year Project (FYP)
Nanyang Technological University