Skip to content
6CCVD Research

Interface-Driven Electrothermal Degradation in GaN-on-Diamond High Electron Mobility Transistors

At a Glance

Section titled “At a Glance”
MetadataDetails
Publication Date2025-07-18
JournalNanomaterials
AuthorsHuanran Wang, Yifan Liu, Xiangming Dong, Jinjiang Sun
InstitutionsState Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University

Abstract

Section titled “Abstract”

Diamond is an attractive substrate candidate for GaN high-electron-mobility transistors (HEMT) to enhance heat dissipation due to its exceptional thermal conductivity. However, the thermal boundary resistance (TBR) at the GaN-diamond interface poses a significant bottleneck to heat transport, exacerbating self-heating and limiting device performance. In this work, TCAD simulations were employed to systematically investigate the effects of thermal boundary layer (TBL) thickness (dTBL) and thermal conductivity (ÎșTBL) on the electrothermal behavior of GaN-on-diamond HEMTs. Results show that increasing the TBL thickness (5-20 nm) or decreasing its thermal conductivity (0.1-1.0 W/(m·K)) leads to elevated hotspot temperatures and degraded electron mobility, resulting in a notable deterioration of I-V characteristics. The nonlinear dependence of device performance on ÎșTBL is attributed to Fourier’s law, where heat flux is inversely proportional to thermal resistance. Furthermore, the co-analysis of substrate thermal conductivity and interfacial quality reveals that interface TBR has a more dominant impact on device behavior than substrate conductivity. Remarkably, devices with low thermal conductivity substrates and optimized interfaces can outperform those with high-conductivity substrates but poor interfacial conditions. These findings underscore the critical importance of interface engineering in thermal management of GaN-diamond HEMTs and provide a theoretical foundation for future work on phonon transport and defect-controlled thermal interfaces.

Tech Support

Section titled “Tech Support”

Original Source

Section titled “Original Source”

References

Section titled “References”
  1. 2011 - Electric-field-driven degradation in off-state step-stressed AlGaN/GaN high-electron mobility transistors [Crossref]
  2. 2017 - Effect of self-heating on electrical characteristics of AlGaN/GaN HEMT on Si (111) substrate [Crossref]
  3. 2025 - Hotspot and nonequilibrium thermal transport in AlGaN/GaN FinFET: A coupled electron-phonon Monte Carlo simulation study [Crossref]
  4. 2006 - A thermal model for static current characteristics of AlGaN/GaN high electron mobility transistors including self-heating effect [Crossref]
  5. 2013 - Simulation of thermal management in AlGaN/GaN HEMTs with integrated diamond heat spreaders [Crossref]
  6. 2021 - Impact of temperature-dependent series resistance on the operation of AlGaN/GaN high electron mobility transistors [Crossref]
  7. 2004 - The ambient temperature effect on current-voltage characteristics of surface-passivated GaN-based field-effect transistors [Crossref]
  8. 2014 - Low thermal resistance GaN-on-diamond transistors characterized by three-dimensional Raman thermography mapping [Crossref]

Reads Similar to This

Point-Defect Nature of the Ultraviolet Absorption Band in AlN Progress in Preparation and Application of Titanium Sub-Oxides Electrode in Electrocatalytic Degradation for Wastewater Treatment Maser threshold characterization by resonator Q-factor tuning