Effects of substrate voltage on noise characteristics and hole lifetime in SOI metal-oxide-semiconductor field-effect transistor photon detector

Abstract

Low-frequency noise and hole lifetime in silicon-on-insulator (SOI) metal-oxide-semiconductor field-effect transistors (MOSFETs) are analyzed, considering their use in photon detection based on single-hole counting. The noise becomes minimum at around the transition point between front- and back-channel operations when the substrate voltage is varied, and increases largely on both negative and positive sides of the substrate voltage showing peculiar Lorentzian (generation-recombination) noise spectra. Hole lifetime is evaluated by the analysis of drain current histogram at different substrate voltages. It is found that the peaks in the histogram corresponding to the larger number of stored holes become higher as the substrate bias becomes larger. This can be attributed to the prolonged lifetime caused by the higher electric field inside the body of SOI MOSFET. It can be concluded that, once the inversion channel is induced for detection of the photo-generated holes, the small absolute substrate bias is favorable for short lifetime and low noise, leading to high-speed operation.

(Invited) Characteristics of Si Single-Electron Transistor under Illumination

“…Photo-excited carriers in Si quantum islands also show another interesting features such as single-electron CCD [20] where electrons and holes exist in the same island at the same time. In a SET, when a few holes generated by photo-excitation are trapped in the one side of the SET island under the vertical electric field, the number of trapped holes is detected by the electron current flowing through the other side of the island [21][22][23][24][25]. Since the number of the electrons in the SET island determines the transport characteristics, extra holes reduces the effective total number of electrons and make it possible to show the current peak at the lower gate voltage than that of the first peak as if the number of electrons was negative.…”