Microwave-induced hydrogen plasma in a quartz bell-jar type MPCVD process: a multi-physics simulation approach

Abstract

Plasma-based simulation enables precise control of plasma dynamics and temperature fields, essential for optimizing reactor design and achieving uniform, high-quality film growth. In this work, a multi-physics modelling approach was used to study the effect of microwaves on hydrogen plasma generation in a quartz bell-jar type MPCVD reactor. A 2D axisymmetric finite element model of the reactor was developed to analyse the hydrogen plasma at high-frequency and low-pressure conditions by employing electromagnetic and heat transfer solvers. The simulated electron density data generated by the developed model were found to be in reasonable agreement with electron density data reported in the literature. The simulation results indicate that variation in the input microwave powers (500 W, 1000 W, 1500 W, 2000 W, 2500 W, and 3000 W) at a constant gas pressure of 90 Torr substantially influences the electric field strength (59.17% higher at 3000 W) and electron density (76.84% higher at 3000 W) as compared to that of 500 W. The maximum simulated electron density, hydrogen atom density, and resistive losses at 3000 W were 8.29 × 1017 m−3, 18.04 × 1022 m−3, and 1.38 × 108 Wm−3 at arc lengths of 0.45 × 10−2 m, 1.8 × 10−2 m, and 0.106 × 10−2 m, respectively, above the substrate holder.