A W-Band Improved Small-Signal Model for AlGaN/GaN HEMT

At present, the application prospects of GaN HEMT is very broad, especially in the fields of communication, radar and others. The two-dimensional electron gas (2DEG) generated by the GaN HEMT due to heterojunction and the wide band gap advantage of GaN base materials can meet the current demand for high-frequency and high-power devices. However, during the design process of the GaN HEMT monolithic microwave integrated circuit (MMIC), due to the complex parasitic effect under high frequency, the study of the GaN HEMT small signal model under high frequency is essential. This article mainly studies the small signal model of the GaN HEMT under the W-band and proposed the following innovations: Considering the inductance effect of the existence of the transmission line under high frequency, the parasitic inductances L<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">PLUS1</inf> and L<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">PLUS2</inf> are added to the gate and drain, which constitutes a 28-element model. After that, aims to solve the lack of traditional parameters extraction, the idea of a segment model is proposed. The 100MHz-10GHz is divided into three frequency bands to extract parameters and optimize parameters, which achieves higher fitting accuracy of the measured S parameters and simulation S parameters in each frequency band.