Design of Low Loss Radio Frequency Switch Device Based on Double-Channel InAlN/GaN HEMT

In this work, the effect of InAlN/GaN double heterojunction on the performance of RF switching devices has been investigated. Using InAlN material and introducing double heterojunction structure can optimize the insertion loss of switching devices by reducing the on-resistance. Compared with single-channel AlGaN/GaN HEMTs on SiC wafers, double-channel InAlN/GaN HEMTs on SiC wafers exhibit better saturation current density and lower on-resistance of the linear zone, which makes them better than the former at Sub 6GHz with 1dB insertion loss. InAlN epitaxial materials have a wide application prospect in the switching part of RF front-end receiver modules.

I. Introduction

In recent years, GaN HEMTs have been comprehensively demonstrated and adopted as RF switches in the signal conversion units of satellite communication systems (VSAT) or hub stations. For 5G communication systems, RF switches require lower insertion losses, especially at the signal-receiving end. At present, the optimization of GaN HEMT switching devices mainly starts from the structure and materials. On the one hand, NGES has reported on a new transistor structure based on GaN super lattice channels and 3D gates, named SLCFET (Superlattice castle field effect transistor), and has found that the multi-channel structure had a significant reduction in on-resistance, which greatly optimized the insertion loss of RF switches [1]. On the other hand, InAlN epitaxial materials have been extensively studied in low-voltage and high-frequency applications [2]. Compared with conventional AlGaN/GaN hetero structures, lattice-matched In0.17Al0.83N/GaN heterostructures are more suitable for HEMT low-insertion loss switching devices because of higher carrier mobility and higher two-dimensional electrical concentration. However, little has been reported about InAlN/GaN HEMT RF switches. In this paper, the effects of two different epitaxial designs on the performance of RF switches are systematically compared, which provides a broader idea for designing HEMT switches based on InAlN double-channel.