Title :
Mech1anism and Control Technology of Trench Corner Rounding by Hydrogen Annealing for Highly Reliable Trench MOSFET
Author :
Shimizu, Ryosuke ; Kuribayashi, Hitoshi ; Hiruta, Reiko ; Sudoh, Koichi ; Iwasaki, Hiroshi
Author_Institution :
Fuji Electr. Adv. Technol. Co. Ltd., Tokyo
Abstract :
The shape transformation mechanism of micron-size silicon trenches during high-temperature annealing (ges1000degC) in hydrogen ambient was studied, focusing on the effect of hydrogen pressure on the trench corner curvature. Results demonstrated the effectiveness of this hydrogen annealing process on the reliability of gate SiO2 films; after hydrogen annealing at 1030degC for 1 min, the leakage current through trench gate SiO2 as a function of applied voltage to the poly-Si gate was suppressed by over 2 orders of magnitude. The time-dependent dielectric breakdown (TDDB) characteristics of the trench gate SiO2 under a constant applied stress current of 50mA/cm was significantly improved by hydrogen annealing in the initial stage (<100sec) of dielectric breakdown
Keywords :
MOSFET; annealing; hydrogen; semiconductor device breakdown; semiconductor device reliability; silicon compounds; wide band gap semiconductors; 1 min; 1030 C; SiO2; high-temperature annealing; leakage current; micron size silicon trenches; poly-Si gate; shape transformation mechanism; stress current; time-dependent dielectric breakdown; trench MOSFET; trench corner rounding; Annealing; Dielectric breakdown; Hydrogen; Laboratories; Leakage current; MOSFET circuits; Materials science and technology; Scanning electron microscopy; Shape; Silicon;
Conference_Titel :
Power Semiconductor Devices and IC's, 2006. ISPSD 2006. IEEE International Symposium on
Conference_Location :
Naples
Print_ISBN :
0-7803-9714-2
DOI :
10.1109/ISPSD.2006.1666084
