A Study On The Silicon Based High Performance TFET And Stru Ctural Optimization

Microelectronics technology has entered the nanometer size, the emergence of problems such as short channel effects and high-frequency parasitic effects at high speed makes traditional IC technology more and more difficult to meet the requirements of the electronics industry, especially the challenges posed by the worsening problem of circuit power consumption has become the biggest obstacle to the continuation of Moore’s law. In order to solve the problems that encountered on the road of IC development, academia presents PIN-type tunneling field effect transistor(TFET) to replace existing MOSFETs technology, due to it can present more steep-subthreshold characteristics than the traditional CMOS devices and then has become the research topic. This paper is undertaken on this hot issue. By Comparing the principles of TFET(band to band tunneling) and MOSFET(diffusion and drift of carriers), the advantages and disadvantages of both has been obtained. Based on the TFET as the object of study, the device working mechanism has been analyzed, the device structure has been improved, and a TFET structure is proposed to improve the output transfer characteristics of the device. Specific research methods and results are the study on TFET’s mechanism and the output characteristics. Based on the analysis of PIN TFET structure, by using Silvaco TCAD, the principles and basic output characteristics are systematically studied. The research results show that PIN-based structure of the tunneling field effect transistor with tunneling principles, through the gate voltage adjust the energy band structure of the barrier area, further increasing the carrier tunneling probability to achieve the shifts of device status. Based on working mechanism of tunneling field effect transistor, proposed and solved by using the partition method of electric field, electric potential of different regions, the doping concentration of the source region, the drain region and the intrinsic zone was discussed, I-layer doping concentrations, insulating layers dielectric constant influence of physical parameters on the output device characteristics. And the tunneling field effect transistor structure parameters are optimized. Using Silvaco Atlas analyses the structure parameters and electrical characteristics, proposed the tunneling field effect transistor performance optimization solutions. Through the use of high concentration of source areas, low concentration of the drain region, using a mixture of high dielectric constant and low dielectric constant of the insulation material, PI junction barrier area parallel to the metal edge of the gate, using metal source enables the TFET characteristics show the best performance.In summary, in this paper, the TFET has been studied and according to the existing problems of TFET, novel device structure which can improve the characteristics of TFET has been proposed.