Study On Band Structures And Mobility Model Of PD-Ge Semiconductor And Inversion Layer

IC industry has been following and advancing the evolution of Moore's law on the basis of Si based devices.However,with the increase of microelectronic circuit operating frequency and the decrease of device size,the influence of the parasitic effect on chip speed,power consumption and reliability can not be ignored.In order to further improve the performance and integration of semiconductor devices,researchers seek solutions from materials,device structure and other multi-direction,photoelectric integration technology has become one of the research focus.The energy difference between the ? energy valley and the L energy valley decreases under tensile stress.the band structure of Germanium(Ge)semiconductors can be transformed from the indirect band gap type to the direct band gap type semiconductor(PDGe).Combined with heavy doping,the carrier radiation recombination efficiency and carrier mobility of the PD-Ge semiconductor are greatly improved,which is suitable for manufacturing optical devices and high-speed electronic devices.The energy band structure model and mobility model are the key to improve the design of optoelectronic devices as the theoretical basis of the device research in monolithic one-layer optoelectronic integrated system,but there is still a lack of relevant reports in the current research on PD-Ge,especially on the PD-Ge MOS inversion layer energy band structure and mobility model.On this basis,the dispersion relation model and energy band parameter model of PD-Ge conduction band valence band structure are established by using k.p perturbation theory and single electron approximation method.The energy band structure and its key physical properties of PD-Ge MOS channel inversion layer are studied on the base of band structure.Moreover,the dispersion relation model PD-Ge energy band structure established in this paper is verified by PD-Ge material preparation and PL spectrum analysis.On the basis of the band structure model established in this paper,considering various scattering potential energies according to Fermi gold rule and combining with the approximate relation of collision term of Boltzmann equation,we propose to obtain various scattering mechanism models of PD-Ge electrons and holes,and further study the physical parameters to establish a quantitative analytical mobility model of PD-Ge carrier in both body material and MOS inversion layers.Furthermore,the results of PD-Ge carrier mobility model are verified by Monte Carlo simulation method.At the last,based on the relevant quantitative conclusions of band structure and carrier mobility in PD-Ge semiconductor and inversion layer,a PD-Ge P type MOSFET structure with 50 nm channel length is proposed.The PD-Ge MOS device model is simulated by TCAD tools,and the simulation results are analyzed.based on this,combined with the study of the working mechanism of MOS devices,the influence of channel length,gate dielectric thickness,substrate doping concentration and other device model structural parameters on the device-related electrical properties is simulated and discussed.This paper intends to study on the theoretical calculation research and establish a quantitative analytical model of PD-Ge the energy band structure and mobility in PD-Ge semiconductor and MOS inversion layer,which may provide an important theoretical basis for the understanding of PD-Ge material physics and the design of single-layer optoelectronic integrated system for single-chip materials.