Analysis Of Characteristics And Models For Novel Micro-nano Photodectors

The devices of Quantum well infrared photodetectors(QWIP),Avalanche photodetectors(APD)and Resonant cavity enhanced photodiodes(RCE-PD)which baseⅢ-Ⅴmaterials are very important for different application field.In those investigations,theoretical calculation may be a good way for directing the experiment for proving the results of experiment.In a word,the theory research by simulation has an important sense for scientific research.In this paper,the three devices mentioned above have been investigated.The models of devices,the comparison between the same type devices but different structure or materials and the optimization have been investigated principally.The main content shows as follows:1.Based Al_xGa_1-xAs/GaAs and In_xGa_1-xAs/GaAs material system QWIP characteristics calculated in this paper,APSYS software be employed in simulation, the absorption spectrums of theirs have compared.The simulation results show that In_xGa_1-xAs/GaAs QWIP has higher absorption coefficient at very long wavelength.A reasonable circuit model was set up for Al_0.15Ga_0.85As/GaAs and In_0.15Ga_0.85As/GaAs QWIPs.Bias dependence of the dark current,photocurrent and responsivity is accurately described by the model in Spice,The result demonstrated that the responsivity and quantum efficiency of In_0.15Ga_0.85As/GaAs QWIP are better than Al_0.15Ga_0.85As/GaAs QWIP's.In addition,THz QWIPs with the structure Al_0.05Ga_0.95As/GaAs also be simulated,there is a good result agree with experiment at 50K.2.The InGaAsP/InP APD simulate.Apsys software can be used for simulations of the material bandgap,electric field,the dark current and photo current and so on.The performance of InGaAs/InP avalanche photodiode(APD)which have a thin sectional charge layer has studied.By change the P percent in InGaAsP charge layer,the heterostructure can get optimization,when the P element percent changed between 0 and 30 would obtain appropriate SACM APD structure and a lower leakage current. Simulation demonstrated that at the same condition SAGCM structure may has better characteristics than SACM,the lower leakage current and higher gain could get in SAGCM APD,that is option the thin charge layer,thin multiplication layer,and the grading layer with high doping.3.The primary principle of RCE-PD has been demonstrated for example Distribute Bragg Reflection mirror(DBR),the materials choosing,thickness,different periods DBR.Especially the quantum efficiency performance of device investigated mainly.