Reliability study on positive bias temperature instability in SiC MOSFETs by fast drain current measurement

Abstract

The gate threshold voltage (Vth) shift under positive gate bias stress is one of the most important reliability concerns in silicon carbide metal–oxide–semiconductor field effect transistors (SiC MOSFETs). Because dynamic recovery is observed as soon as the gate bias stress is removed, it is remarkably difficult to accurately evaluate Vth shifts. Many studies have focused on how to evaluate Vth shifts of SiC MOSFETs under positive gate bias stress. In this study, this issue is investigated by introducing a fast measurement technique. We show that the measured Vth shift is modified to take the Vth recovery term into consideration. Furthermore, we show that the Vth shift is a saturation phenomenon and that the maximum Vth shift can be predicted using an electron capture and emission model.

Characterization of Oxide Trapping in SiC MOSFETs Under Positive Gate Bias

“…In Fig. 7 (d), the subthreshold swing decreases at high temperatures due to the alleviated Coulomb scattering effect [3], [28]- [30].…”

“…To obtain the capture/emission time constant and describe the distribution of defects in the oxide layer, the ΔV TH data in Fig. 8 (a) and (b) are fitted with the stretched exponential functions by using the following Equations ( 4) and ( 5), with the high R-square values between 0.95 to 0.99 (dash fitted line) [3], [26]- [28].…”

“…ilicon carbide (SiC) is considered a promising wide bandgap semiconductor material to supersede silicon for developing high-efficiency, high-power, and hightemperature electron devices [1]. In particular, SiC metaloxide-semiconductor field-effect transistors (MOSFETs) are expected to meet the growing demand for electrical power generation, distribution, and switching due to their high breakdown voltage, low conduction, and low switching loss capabilities [2], [3].…”

Análisis comparativo del nivel de defectuosidad en los dispositivos de potencia SiC MOSFETs

“…Debido a su amplio Bandgap, campo eléctrico critico y conductividad térmica, Los dispositivos MOSFETs fabricados en silicio de carburo pueden trabajar a temperaturas mayores, mayor densidad de potencia, mayores frecuencias y mayor voltaje que los dispositivos de MOSFETs fabricados en silicio. Aunque las técnicas avanzadas de fabricación de dispositivos han llevado a mejoras importantes en los últimos años, [1][2][3][4][5][6][7][8][9] los dispositivos disponibles en el mercado aún funcionan por debajo de sus límites teóricos. A pesar de todos esos beneficios conocidos, tomó 10 años después del exitoso lanzamiento al mercado de diodos de SiC en 2001 por Infineon.…”

“…A pesar de todos esos beneficios conocidos, tomó 10 años después del exitoso lanzamiento al mercado de diodos de SiC en 2001 por Infineon. [3] que Rohm y Cree (hoy Wolfspeed) lancen los primeros MOSFET SiC productivos en 2011/2012. Entre 2012 y 2016, otros fabricantes de dispositivos como ST Microelectronics, Microsemi y otros han enriquecido aún más la cartera de tecnologías SiC MOSFET en el mercado.…”