Congratulations to Wang Zhengda for publishing a journal paper in the well-known journal Advanced Materials Interfaces

Congratulations to Wang Zhengda for publishing a journal paper entitled "Exploration of Physical Chemical Mechanism for Negative Bias Temperature Instability in GaN-HEMTs by Extracting Activation Energy of Dislocations" on the international journal Advanced Materials Interfaces

Article web link：https://onlinelibrary.wiley.com/doi/10.1002/admi.202200871

Introduction to the article:

Reliability issues caused by negative bias temperature instability (NBTI) have hindered the rapid scaling of gallium nitride (GaN)-based high electron mobility transistors (HEMTs). Unraveling the physicochemical reactions during NBTI-induced degradation is crucial to trace the origin of NBTI, thereby circumventing inherent reliability issues. However, the investigation of the deep-seated reasons behind NBTI-related problems still lacks feasible avenues and has not been explored in depth. In this paper, a joint approach combining electrical measurements, materials analysis, and theoretical calculations is presented to comprehensively investigate the molecular basis of degradation proposed by NBTI. Activation of extracted dislocations during stress can effectively identify deep sources of device degradation. According to the theoretical calculation of activation energy, the breaking of N-H bonds and the migration of hydrogen ions along the dislocations in the GaN lattice are the main causes of electrical instability, which is also proved by material characterization including transmission electron microscopy, X-ray photoelectron spectroscopy and Raman analysis. In addition, a molecular-level model showing the reaction kinetics was established, which can fundamentally understand the key physicochemical mechanism behind NBTI, thus providing a direction for further optimization of GaN electronic devices.