Lateral Photovoltaic And Magnetically Modulated Laser-induced Resistance Effect In Cr/SiO₂/Si Structure

Metal-Oxide-Semiconductor?MOS?structures,as the core structure of microelectronic devices,have received plenty of attention in both academic and industry.Cr?Chromium?metal films recently became the focus of some research on electron spin due to its anti-ferromagnetic spin density wave.Cr/SiO₂/Si is a kind of MOS structure with Cr films,which we have found has some special optical and electrical properties,may have important applications in microelectronic devices.This thesis researches lateral photovoltaic effect?LPE?and magnetically modulated laser-induced resistance effect in Cr/SiO₂/Si structure.The major achievements are:?a?LPE observed in Cr/SiO₂/Si structure:Based on Cr/SiO₂/Si structure,LPE on Cr film has a sensitivity of42mV/mm.Furthermore,by measuring samples with different thickness of Cr films,we found that the electronic transport characteristics of the structure will determine the performance of the LPE,the thickness of Cr film is an important factor to improve sensitivity.This discovery could help to study the charge transfer mechanism of nanometer metal film MOS structure and the role of photoelectron in the photovoltaic effect?PE?.?b?Magnetically modulated laser-induced resistance effect observed in Cr/SiO₂/Si structure:Based on Cr/SiO₂/Si structure,we can obtain a space sensitivity of 0.79 M?/mm and resistance change ratio up to 2100%in the laser-induced resistance effect.With an additional magnetic field applied,the resistance change ratio can increase to 2530%,after analysis it,we attributed the mechanism of magnetically modulation to the Lorentz force on the high mobility light-induced carriers in the inversion layer;This work provides a new idea of photoelectric devices application research,these new photoelectric device can be sensitive for additional magnetic field,such as magnetic susceptibility photoelectric sensors,magnetic control photoelectric switch,magnetic field regulating transistor and diode and even the new magneto optical storage device,etc.The research results of the work also provide a new way for the design of MOS multifunctional devices,possibly open up a new research hotspot of photoelectric effect with composite external field modulation.