A direct tunneling model through gate dielectric s in CMOS devices in the frame of WKB approximation is reported.In the model,an im proved one-band effective mass approximation is used for the hole quantization, where valence band mixing is taken into account.By comparing to the experiments, the model is demonstrated to be applicable to both electron and hole tunneling c urrents in CMOS devices.The effect of the dispersion in oxide energy gap on the tunneling current is also studied.This model can be further extended to study th e direct tunneling current in future high-k materials.
The changes in photoluminescence and FTIR spectra of porous silicon subjected to oxidation were exdrined. With the increase of okidizing duxation, the relative amount of the Si-H2 surface species on PS decreases even though the photoluminescence intensity increases. the result suggests that it isn’t SiH2 but Si-O and Si-O-Si on theinterface of PS play a key role in enhancing the pllotoluminescence. A complete photoluminescence mechanism should consider the influence of su-rface state of porous silicon based on the quantum codriement effect model.
