This study presents numerical simulation of a novel gallium nitride buffered trench gate (GaN-BTG) metal oxide semiconductor field effect transistor (MOSFET) for high-speed and low-power applications. The electrical characteristics of GaN-BTG-MOSFET are compared with BTG MOSFET and conventional trench gate MOSFET. A comparative study of different performance factors such as electric field, electron velocity, threshold voltage (V th), electron mobility, and sub-threshold swing (SS) of these devices has been performed. Results reveal a 43.85% improvement in SS and 9.83% decrement in V th for GaN-BTG-MOSFET. Furthermore, the frequency analysis has been performed in terms of scattering (S) parameters, cut-off frequency (f T) and maximum oscillator frequency (f MAX) to show how the device is also suitable for radio frequency applications. Furthermore, the study of parametric variation of GaN-BTG-MOSFET with the change in channel length, oxide thickness (t ox), and doping concentration has also been presented. Results show that GaN-BTG-MOSFET can act as a promising structure for further scaling down of the trenched MOSFET and assures better performance for sub-20 nm trenched MOSFET.

https://ietresearch.onlinelibrary.wiley.com/doi/pdf/10.1049/iet-cds.2020.0041

Numerical simulation and parametric assessment of GaN buffered trench gate MOSFET for low power applications

Modeling of minimum surface potential and sub-threshold swing for grooved-gate MOSFETs

A new U groove channel implanted lateral MOSFET structure, suitable for synchronous rectifier application, has been presented The conversion efficiency of MOSFET based isolated DC/DC converters with synchronous rectification, have been evaluated A detailed analysis of their operation and performance, has been discussed The dependence of efficiency on input primary duty cycle and output voltage, and also on the critical duty cycle, has been analysed The region of optimum operation has been suggested The new MOSFET structure proposed in this work, includes a channel implanted U groove gate The variation of the non uniform lateral concentration profile is responsible for a higher channel current for a desired threshold voltage Based on an analytical model the effects of the groove angle, dose and energy of the implantation and other groove dimension, on the electrical performance of the device was carried out The simulation results demonstrates that if properly optimised, higher current conduction at desired threshold voltage, as compared to a conventional MOSFET can be achieved Experimental results obtained from fabricated test device structure supports the simulated current-voltage characteristics based on the model Due to lower channel resistance, as compared to conventional MOSFET with planar gate configuration, it can be concluded that the proposed structure is suitable for synchronous rectifier application in DC/DC converters and is also integrable for SMART low voltage switching regulator modules

http://ieeexplore.ieee.org/iel5/9254/29354/01330035.pdf

A new grooved gate lateral power MOSFET structure for synchronous rectification in DC/DC converters

The subject matter disclosed herein relates to metal-oxide-semiconductor (MOS) devices, such as silicon carbide (SiC) power devices (e.g., MOSFETs, IGBTs, etc.). A semiconductor device includes a well region extending a first depth into a surface of an epitaxial semiconductor layer positioned above a drift region. The device includes a junction field-effect transistor (JFET) region positioned adjacent to the well region in the epitaxial semiconductor layer. The device also includes a trench extending a second depth into the JFET region, wherein the trench comprises a bottom and a sidewall that extends down to the bottom at an angle relative to the surface of the epitaxial semiconductor layer.

Semiconductor device having gate trench in JFET region

In a grooved-gate MOSFET with a U-grooved gate and a ion-implanted channel, the lateral concentration profile of the channel is non-uniform. This has a remarkable influence on the current-voltage characteristics of the device. An analytical model based on the non-uniform lateral concentration profile along the channel for a long-channel grooved-gate MOSFET has been developed to investigate the effects of the groove angle, dose and energy of the channel implantation and other groove dimensions on the electrical performance of the device. The simulation results demonstrates that if properly optimized, higher current conduction at a desired threshold voltage with improved breakdown voltage, as compared with a conventional MOSFET can be achieved. Experimental results from a fabricated test device structure support the simulated current-voltage characteristics based on the model.

B. Majumdar

Papers

Studies on the effect of channel implantation on the drain current of a grooved-gate MOSFET