The aim of this article is to investigate the effect of dielectric loss tangent on frequency dispersion of output reactance and capacitance in GaAs MESFETs.For this purpose,measurements of output impedance modulus and...The aim of this article is to investigate the effect of dielectric loss tangent on frequency dispersion of output reactance and capacitance in GaAs MESFETs.For this purpose,measurements of output impedance modulus and phase have been carried out within a frequency range of 10 Hz to 10 kHz,and various voltage values of gatesource（Vgs= 0,-0.2,-0.3,-0.35,-0.4,-0.45,-0.5 and-0.6 V） and drain-source（Vds= 0.7,0.9,1,1.5and 2 V） Based on the concept of complex permittivity of semiconductor material,complex capacitance is used to analyze and simulate frequency dispersion of output reactance and capacitance of GaAs MESFETs.The results show that conductor losses which dominate the dielectric loss tangent are attributed to trapping mechanisms at the interface of devices;so they influence the frequency dispersion of output reactance and capacitance in particular at low frequencies.This reveals that frequency dispersion of these parameters is also related to dielectric loss tangent of semiconductor materials which affects the response of electronic devices according to frequency variation.展开更多
We present an approach of GaAs MESFET incorporating the gate engineering effect to improve immunity against the short channel effects in order to enhance the scaling capability and the device performance for microwave...We present an approach of GaAs MESFET incorporating the gate engineering effect to improve immunity against the short channel effects in order to enhance the scaling capability and the device performance for microwave frequency applications. In this context, a physics-based model for I–V characteristics and various microwave characteristics such as transconductance, cut-off frequency and maximum frequency of oscillation of submicron triple material gate（TM） GaAs MESFET are developed. The reduced short channel effects have also been discussed in combined designs i.e. TM, DM and SM in order to show the impact of our approach on the GaAs MESFETs-based device design. The proposed analytical models have been verified by their good agreement with 2D numerical simulations. The models developed in this paper will be useful for submicron and microwave analysis for circuit design.展开更多
文摘The aim of this article is to investigate the effect of dielectric loss tangent on frequency dispersion of output reactance and capacitance in GaAs MESFETs.For this purpose,measurements of output impedance modulus and phase have been carried out within a frequency range of 10 Hz to 10 kHz,and various voltage values of gatesource（Vgs= 0,-0.2,-0.3,-0.35,-0.4,-0.45,-0.5 and-0.6 V） and drain-source（Vds= 0.7,0.9,1,1.5and 2 V） Based on the concept of complex permittivity of semiconductor material,complex capacitance is used to analyze and simulate frequency dispersion of output reactance and capacitance of GaAs MESFETs.The results show that conductor losses which dominate the dielectric loss tangent are attributed to trapping mechanisms at the interface of devices;so they influence the frequency dispersion of output reactance and capacitance in particular at low frequencies.This reveals that frequency dispersion of these parameters is also related to dielectric loss tangent of semiconductor materials which affects the response of electronic devices according to frequency variation.
文摘We present an approach of GaAs MESFET incorporating the gate engineering effect to improve immunity against the short channel effects in order to enhance the scaling capability and the device performance for microwave frequency applications. In this context, a physics-based model for I–V characteristics and various microwave characteristics such as transconductance, cut-off frequency and maximum frequency of oscillation of submicron triple material gate（TM） GaAs MESFET are developed. The reduced short channel effects have also been discussed in combined designs i.e. TM, DM and SM in order to show the impact of our approach on the GaAs MESFETs-based device design. The proposed analytical models have been verified by their good agreement with 2D numerical simulations. The models developed in this paper will be useful for submicron and microwave analysis for circuit design.
