OFF-state TDDB in High-Voltage GaN MIS-HEMTs
نویسنده
چکیده
We have investigated time-dependent dielectric breakdown (TDDB) in high-voltage AlGaN/GaN MetalInsulator-Semiconductor High Electron Mobility Transistors (MIS-HEMTs) biased in the OFF state. This is an important reliability concern that has been overlooked. Towards this goal, we have developed a novel methodology using ultraviolet light that allows us to separate the permanent effects of dielectric degradation from the transient behavior due to trapping after high voltage stress. This new approach reveals unmistakable evidence of TDDB at the drain end of the gate in the OFF state. This mechanism must be accounted for in device lifetime estimation models. Furthermore, trapping emerges as a significant complication in the study of OFF-state TDDB. If uncontrolled, trapping effects can lead to a dramatic overestimation of device breakdown voltage.
منابع مشابه
15.4 Stress and Characterization Strategies to Assess Oxide Breakdown in High-Voltage GaN Field-Effect Transistors
GaN metal-insulator-semiconductor high electron mobility transistors (MIS-HEMTs) are promising for high-voltage power switching applications. A concern with this new device technology is oxide reliability under prolonged high-field and high-temperature conditions. This paper studies an important aspect of oxide reliability, time-dependent dielectric breakdown (TDDB) in GaN MIS-HEMTs. We have de...
متن کاملEvaluation and Reliability Assessment of GaN-on-Si MIS-HEMT for Power Switching Applications
This paper reports an extensive analysis of the physical mechanisms responsible for the failure of GaN-based metal–insulator–semiconductor (MIS) high electron mobility transistors (HEMTs). When stressed under high applied electric fields, the traps at the dielectric/III-N barrier interface and inside the III-N barrier cause an increase in dynamic on-resistance and a shift of threshold voltage, ...
متن کامل8.3 High-Performance Normally-off GaN MIS-HEMTs with Dual Gate Insulator employing PEALD SiNx Interfacial Layer and RF-sputtered HfO2
To fabricate high-performance GaN MIS-HEMTs, we have employed a novel SiNx/HfO2 dual gate insulator. A PEALD technique was used for very thin high quality SiNx (5 nm) as an interfacial layer, followed by RFsputtered HfO2 as a high-k dielectric for the second gate insulator structure. As a result, we have achieved excellent characteristics such as small subthreshold slope of 85 mV/dec, extremely...
متن کاملOn the Operation Mechanism and Device Modeling of AlGaN/GaN High Electron Mobility Transistors (HEMTs)
In this work, the physical based device model of AlGaN/GaN high electron mobility transistors (HEMTs) has been established and the corresponding device operation behavior has been investigated also by using Sentaurus TCAD from Synopsys. Advanced AlGaN/GaN hetero-structures with GaN cap layer and AlN spacer have been considered and the GaN cap layer and AlN spacer are found taking important role...
متن کاملAlGaN/GaN High Electron Mobility Transistor degradation under on- and off-state stress
AlGaN/GaN High Electron Mobility Transistors (HEMTs) with various gate lengths have been stepstressed under both onand off-state conditions. On-state, high power stress tests were performed on 0.17 lm gate length HEMTs and a single 5 lm spaced TLM pattern. Significant degradation of the submicron HEMTs as compared to the excellent stability of the TLM patterns under the same stress conditions r...
متن کامل