Title :
Comparison of bipolar bias-temperature instability on MOSFETs with HfO2/LaOx and HfO2/AlOx dielectric stacks
Author :
Lu, Chun-Chang ; Chang-Liao, Kuei-Shu ; Tsao, Che-Hao ; Wang, Tien-Ko
Author_Institution :
Dept. of Eng. & Syst. Sci., Nat. Tsing Hua Univ., Hsinchu, Taiwan
Abstract :
The effects of stress polarity in bias-temperature instability (BTI) tests on high-¿ gate dielectric stacks were studied based on the distribution of interface traps and bulk traps extracted by modified charge-pumping (CP) techniques. The bipolar bias-temperature instability were compared between MOSFETs with HfO2/LaOx and HfO2/AlOx dielectric stacks. From the results of interface trap density (Nit) generation, the positive (PBT) stress and negative (NBT) stress would cause different kinds of traps at different locations. The excellent reliability for HfO2 high-¿ dielectric with the incorporation of La or Al could be attributed to the reduction of oxygen vacancy related traps.
Keywords :
MOSFET; aluminium compounds; dielectric materials; hafnium compounds; high-k dielectric thin films; interface states; lanthanum compounds; semiconductor device reliability; semiconductor device testing; stress effects; vacancies (crystal); BTI tests; HfO2-AlOx; HfO2-LaOx; MOSFET; bipolar bias temperature instability; bulk trap distribution; charge pumping technique; high-?? gate dielectric stacks; high-¿ gate dielectric stacks; interface trap density; interface trap distribution; negative stress; oxygen vacancy; positive stress; reliability; stress polarity; Charge pumps; Dielectric devices; Dielectric measurements; Hafnium oxide; High-K gate dielectrics; MOS devices; MOSFETs; Stress measurement; Temperature; Voltage;
Conference_Titel :
Semiconductor Device Research Symposium, 2009. ISDRS '09. International
Conference_Location :
College Park, MD
Print_ISBN :
978-1-4244-6030-4
Electronic_ISBN :
978-1-4244-6031-1
DOI :
10.1109/ISDRS.2009.5378243
