Enhancement of Light-to-Dark Current Ratio via Coupling Effect for MIS (p) Tunnel Diode Photo Sensors
Journal
Electrochemical Society Transactions
Journal Volume
77
Journal Issue
5
Pages
3312-3316
Date Issued
2017
Author(s)
Abstract
The current of metal-insulator-semiconductor (MIS) tunnel diodes is dependent on the Schottky barrier height and there are different mechanisms which dominate MIS tunnel currents while MIS tunnel diodes are biased at positive and negative voltages. In this work, coupled current-voltage behaviors were observed in a MIS(p) tunnel diode with a MOS structure coupled nearby (1). It was found that the MIS(p) saturation tunneling current could be controlled by the voltage bias (VG) of the nearby MOS capacitor. While Inchanges, the minority carrier distribution at the fringe of the MIS tunnel diode also changes. As a result, by well-controlling VG, the light to dark current ratio Ilight/Idark can be effectively enhanced. In this study, two intensities of illumination on MIS(p) tunnel diodes of three different oxide thicknesses were displayed. It is shown that under both intensities of illumination, the light to dark current ratio Ilight/Idark are all effectively enhanced by well-controlling VG. It is also found that the maxima of current ratio Ilight/Idark take place at different values of VG for different intensities of illumination. The coupling effect plays an important role in this phenomenon. © The Electrochemical Society.
Other Subjects
Charge carriers; Dark currents; Diodes; Integrated circuits; Metal insulator boundaries; MIS devices; Schottky barrier diodes; Tunnel diodes; Dark current ratio; Different mechanisms; Metal-insulator-semiconductors; Minority carrier; Negative voltage; Schottky barrier heights; Tunnel currents; Tunneling current; Image enhancement
Type
journal article