Reliability Assessment of On-Wafer AlGaN/GaN HEMTs: The Impact of Electric Field Stress on the Mean Time to Failure

• Published in: Micromachines (Basel) 2023-09, Vol.14 (10), p.1833
• Main Authors: Chakraborty, Surajit, Kim, Tae-Woo
• Format: Article
• Language: English
• Subjects: AlGaN/GaN HEMTs; Aluminum gallium nitrides; Analysis; channel temperature; Current leakage; electric field; Electric fields; Electrostatic discharges; Energy dissipation; Etching; Failure analysis; Gallium nitrides; High electron mobility transistors; Investigations; Leakage current; Mean time to failure; Organic chemicals; Radio frequency; Reliability analysis; Satellite communications; stress voltage; Temperature; Threshold voltage; Transistors
• ISSN: 2072-666X; 2072-666X
• DOI: 10.3390/mi14101833

We present the mean time to failure (MTTF) of on-wafer AlGaN/GaN HEMTs under two distinct electric field stress conditions. The channel temperature ( ) of the devices exhibits variability contingent upon the stress voltage and power dissipation, thereby influencing the long-term reliability of the devices. The accuracy of the channel temperature assumes a pivotal role in MTTF determination, a parameter measured and simulated through TCAD Silvaco device simulation. Under low electric field stress, a gradual degradation of is noted, accompanied by a negative shift in threshold voltage (Δ ) and a substantial increase in gate leakage current ( ). Conversely, the high electric field stress condition induces a sudden decrease in without any observed shift in threshold voltage. For the low and high electric field conditions, MTTF values of 360 h and 160 h, respectively, were determined for on-wafer AlGaN/GaN HEMTs.