Impact of Different Gate Metals on the RF Performance of Gallium Oxide MOSFET

Abstract

The performance of gallium oxide MOSFET is limited due to the issues associated with the requirement of good contact materials for gate electrode. The single metal layer at the gate electrode does not possess all the suitable material properties such as good adhesive behavior, high work function, and low specific resistance. In this work, the effect of different metals, to modulate the work function of depletion-type gallium oxide MOSFET is studied so as to improve its RF performance. The advantage of work function modulation and energy band aligned gate electrode shows low specific contact resistivity with a good ohmic contact. The key figure of merits (FOMs) for its RF performance investigation includes intrinsic capacitances (Cgs & Cgd), output conductance (gd), transconductance (gm), and cut-off frequency (fT). This work elucidates that the Ti/Au metal stack with high fT value found to be superior for RF applications.

Review—Recent Advances in Designing Gallium Oxide MOSFET for RF Application

“…However, to avoid interdiffusion between Ti and Au metals, Pt as a buffer layer is used and hence, making Ti/Pt/Au metal combination in WBG semiconductor-based MOSFET more suitable for RF applications. 31 Performance Parameters for β-Ga 2 O 3 Semiconductor Based MOS Devices…”

“…Therefore, to evaluate the performance of the transistor operating at high frequency, another FOM is proposed by Baliga, which is called the BHFFOM and can be defined as μ n .E br 2 . 7 For more specific cases, other FOMs are used in 31 which the KFOM is defined as λ.[(c. v sat )/(ε.4π)] 1/2 , 5,7 is used to evaluate the thermal limitations of the device during switching activity.…”

“…The cut-off frequency (f T ) is the most important FOM used in the RF performance evaluation of the transistor. 31 For a MOSFET, it can be defined as f T ≈ g m /2π (C gs + C gd ) ≈ v sat /2πL eff , here L eff is the effective channel length of the MOS device. It can be seen that the f T is directly dependent on the v sat , and GO provides an advantage of high v sat which results in high f T .…”

Effects of polycrystalline GeO2 substrates on the structural, optical and electrical properties of ZnSe thin films

“…Coating thin films onto oxide substrates is in focus of many research sectors due to the unlimited ranges of applications of the oxides. Oxide substrates are used in optoelectronics to produce metal-oxide-fields effect thin film transistors, photodiodes and solar cells [1][2][3]. In nuclear application, oxides are also employed for radiation shielding and radiation attenuation [4,5].…”

A Sensitivity Controllable Thermopile Infrared Sensor by Monolithic Integration of a N-channel Metal Oxide Semiconductor

“…MOSFET, as a basic element in CMOS analog and digital integrated circuit, can control output current between the source and the drain by changing the input voltage at the gate. Apart from this, due to the advantages of low cost, high stability, miniaturization and simple scalability, [23][24][25][26] MOSFET is widely applied in researches of biomolecules tracking, [27][28][29] heavy metal detection, [30][31][32] radio frequency sensing, [33][34][35] signal amplification 36,37 and so on.…”