New methodology for optimal preconditioning of GaN HEMT devices

• Published in: Microelectronics and reliability Vol. 170; p. 115776
• Main Authors: Alam, Maroun, Rustichelli, Valeria, Banc, Christophe, Pieprzyk, Jean-François, Perrotin, Olivier, Ceccarelli, Romain, Trémouilles, David, Matmat, Mohamed, Coccetti, Fabio
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.07.2025
• Subjects: High electron mobility transistors; p-GaN; Preconditioning protocol; Recoverable trapping; Reliability; Threshold-voltage fluctuation; p-GaN; High electron mobility transistors; Reliability; Preconditioning protocol; Recoverable trapping; Threshold-voltage fluctuation
• ISSN: 0026-2714
• DOI: 10.1016/j.microrel.2025.115776

High Electron Mobility Transistors (HEMTs) based on p-type Gallium Nitride (p-GaN) gate have emerged as promising candidates for next-generation high frequency and high-power applications. However, these devices present a threshold-voltage (Vth) fluctuation impacting their performance and reliability over time. While Vth fluctuations have been commonly associated with device aging, recent research has uncovered evidence suggesting that certain variations are unrelated to aging effects but rather stem from potentially recoverable trapping phenomena. This study has demonstrated that the biases applied to the gate and drain contribute to the observed variations in Vth. To mitigate these fluctuations, a systematic methodology is proposed for establishing an optimal preconditioning protocol capable of stabilizing the Vth and ensuring consistent device measurements over different biasing conditions. The optimal electrical preconditioning protocol involves applying a defined voltage to the gate and or to the drain right before Vth measurement, ensuring an acceptable stability of Vth measurements. Furthermore, our findings illustrate that the preconditioning protocol is dependent on the technology of the reference. •The study shows the influence of the gate and drain biases on the threshold voltage variations.•A systematic methodology is proposed to mitigate these fluctuations.•The methodology aims to establish an optimal preconditioning protocol for stabilizing Vth.•The optimal preconditioning involves applying a specific voltage to the gate and/or drain before measuring Vth.•The findings indicate that the effectiveness of the preconditioning protocol depends on the technology used as the reference.