Light emission and detection by metal oxide silicon tunneling diodes

Both NMOS and PMOS light-emitting diodes and photodetectors are demonstrated. For the ultrathin gate oxide, the tunneling gate of metal oxide silicon (MOS) diodes can be utilized as both emitters for light emitting devices and collectors for light detectors. An electron-hole plasma model is used to fit the emission spectra. A surface band bending is responsible for the bandgap reduction in electroluminescence (EL) from the MOS tunneling diode. The dark current of the photodetectors is limited by the thermal generation of minority carrier in the inversion layer. The high growth temperature (1000/spl deg/C) of the oxide can reduce the dark current to a level as low as 3 nA/cm/sup 2/.