Performance enhancement of field effect transistor without doping junctions using In0.3Ga0.7As/GaAs for analog/RF applications

Abstract

Reduction of transconductance related to the junctionless silicon (JL-Si) transistor shows challenges to its performance for analog/radio frequency (RF) applications. An effective way to increase the transconductance of JL-Si device without reducing its performance is to use III–V semiconductor materials with a high carrier mobility/velocity instead of silicon. In the present study, the application of In[Formula: see text]Ga[Formula: see text]As/GaAs structures is proposed in order to enhance the transconductance of double gate JL (DG-JL) with channel length of 10 nm and body thickness of 5 nm. The importance of the thickness of In[Formula: see text]Ga[Formula: see text]As layer as well as the indium mole fraction on the electrical characteristics of the proposed device is shown in terms of the transconductance by a numerical simulator. By decreasing the thickness of the In[Formula: see text]Ga[Formula: see text]As layer down to 1 nm for a specified mole fraction of 0.3, a maximum transconductance of 1.7 mS/um was obtained. Comparing the results of JL-In[Formula: see text]Ga[Formula: see text]As/GaAs device with JL-GaAs, JL-In[Formula: see text]Ga[Formula: see text]As and JL-Si structures, an increase of 21%, 18% and 44% in transconductance, respectively, was found. Moreover, simulation results show that the proposed structure exhibits output resistance of 300 G[Formula: see text], intrinsic gain of 32.5 dB and unity gain cut-off frequency of 513 GHz. Thus, the JL-In[Formula: see text]Ga[Formula: see text]As/GaAs device can be a good candidate for analog/RF applications.