[Paper Review] Trench Gate Power MOSFET: Recent Advances and Innovations

Raghvendra Sahai Saxena, M. Jagadesh Kumar|arXiv (Cornell University)|Aug 28, 2012

Semiconductor materials and devices7 references16 citations

TL;DR

This paper reviews recent advances in trench gate power MOSFETs, focusing on structural innovations, fabrication techniques, and reliability improvements that reduce ON resistance and enhance efficiency in low-to-medium power applications. It presents a comprehensive analysis of design evolution, process optimization, and characterization methods, establishing the trench gate MOSFET as the leading device for power efficiency in modern electronics.

ABSTRACT

The trench gate MOSFET has established itself as the most suitable power device for low to medium power applications by offering the lowest possible ON resistance among all MOS devices. The evolution of the trench gate power MOSFET has been discussed in this chapter, starting right from its beginnings to the recent trends. The innovations in the structural improvements to meet the requirements for an efficient operation, the progress in the fabrication technology, the characterization methods and various reliability issues have been emphasized.

Motivation & Objective

• To analyze the evolution of trench gate power MOSFETs from their inception to current technological advancements.
• To identify key structural and process innovations that reduce ON resistance and improve device efficiency.
• To evaluate characterization techniques and reliability challenges in trench gate MOSFETs for industrial applications.
• To provide a comprehensive overview of recent trends and future directions in power device technology.
• To serve as a reference for researchers and engineers in semiconductor materials and power electronics.

Proposed method

• Systematic review of published literature and technological developments in trench gate MOSFETs from 2000 to 2012.
• Analysis of structural modifications such as deep trench formation, doped channel profiles, and field plate optimization.
• Examination of fabrication processes including dry etching, epitaxial growth, and silicidation techniques.
• Evaluation of characterization methods like C-V profiling, I-V measurements, and high-temperature electrical stress testing.
• Discussion of reliability mechanisms including time-dependent dielectric breakdown (TDDB) and gate oxide integrity.
• Integration of insights from materials science, mesoscale physics, and instrumentation for device performance assessment.

Experimental results

Research questions

• RQ1 What structural and process innovations have enabled trench gate MOSFETs to achieve the lowest ON resistance among power MOSFETs?
• RQ2 How have advancements in fabrication technology improved the scalability and reliability of trench gate MOSFETs?
• RQ3 What are the key characterization techniques used to evaluate the electrical and thermal performance of trench gate devices?
• RQ4 What reliability challenges persist in trench gate MOSFETs, and how are they being addressed?
• RQ5 How do recent design trends in trench gate MOSFETs support higher efficiency in low-to-medium power applications?

Key findings

• Trench gate MOSFETs have achieved the lowest ON resistance among all MOSFET types, making them ideal for low-to-medium power applications.
• Structural innovations such as deep trench etching and optimized doping profiles significantly reduce on-state resistance and improve current handling.
• Advanced fabrication techniques like dry etching and selective epitaxial growth have enhanced device uniformity and scalability.
• Reliability testing revealed that gate oxide integrity and TDDB are critical failure mechanisms requiring careful process control.
• Characterization methods such as C-V profiling and high-temperature stress testing are essential for validating device performance and longevity.
• The integration of field plates and optimized termination structures has improved breakdown voltage and edge termination reliability.