Title :
Anomalous Width Dependence of Gate Current in High-
Metal Gate nMOS Transistors
Author :
Duhan, Pardeep ; Ganeriwala, Mohit D. ; Rao, V. Ramgopal ; Mohapatra, Nihar R.
Author_Institution :
Dept. of Electr. Eng., IIT Bombay, Mumbai, India
Abstract :
This letter analyzes the width dependence of gate current observed in nMOS transistors fabricated using the 28-nm gate-first CMOS process. It is experimentally shown that the gate current density is ~10× lower for 80-nm wide high permittivity (K) dielectrics and metal gate nMOS transistors compared with 1-μm wider ones. The physical mechanism responsible for this anomalous width dependence is identified and attributed to the reduction in the average number of positively charged oxygen vacancies present in HfO2 for narrow width transistors.
Keywords :
CMOS integrated circuits; MOSFET; hafnium compounds; semiconductor device manufacture; CMOS; HfO2; anomalous width dependence; gate current density; high-K metal gate nMOS transistors; size 1 mum; size 28 nm; size 80 nm; Electron traps; Hafnium compounds; Logic gates; MOSFET; Tunneling; HKMG; MOS transistor; device scaling; gate current; metal gate; oxygen vacancies; trap assisted tunneling;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2015.2440445