A new photodetection device, which is composed of a silicon-on-insulator metal-oxide-semiconductor field-effect-transistor (SOI MOSFET) and a pn junction diode, is proposed and the operation is experimentally studied. The photodiode is connected to the body of the SOI MOSFET. Carriers photo generated in the photodiode flow to the body and induce the bipolar action of the SOI MOSFET. As a result, the diode photocurrent is amplified by the SOI MOSFET. This operation is demonstrated by the fabrication of n-channel SOI MOSFET/pn+ photodiode and p-channel SOI MOSFET/n+p photodiode composite devices. Enhancement in current amplification by an electrically floating gate is demonstrated. A rather pronounced current amplification is observed for the n-channel/pn+ device. Shrinkage of gate length results in an increase in the current amplification factor. Current amplification up to about 100 is observed by shrinking the gate length to 0.8 μm.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)