First-principles Study Of Strain Effect And Band To Band Tunneling Of Two-dimensional Single Layer Semiconductor Materials

With the development of science and technology,short channel effect becomes more and more obvious due to channel material length of transistors is getting smaller and smaller.These results weaken the control ability of the gate to the device,leading to poor device performance and increasing power consumption.In order to solve above problems,two-dimensional materials have been considered to replace the bulk material as the channel material of the tunneling field effect transistor.Therefore,it is unavoidable to find a two-dimensional material with excellent electronic properties.In present paper,electronic properties of monolayer?-tellurene and GeP have been calculated by density functional theory?DFT?.Furthermore,the device performance of?-tellurene and GeP tunneling field effect transistors?TFETs?have been systematically investigated using the nonequilibrium Green's function?NEGF?method.In addition,we also calculate the performance of?-tellurene tunneling field effect transistors under the strain.The results indicate that I_on/I_off reaches 10⁵ and subthreshold swing?SS?is smaller than theory limit 60 mV/dec.In addition,the strain also has a great influence on the performance of the device.For the GeP tunneling field effect transistor,the performance along the x direction is better than the y direction because of anisotropic carrier mobility.And its I_on/I_off up to 10⁹,which can well realize the opening and closing of the device.