Title :
Variability Improvement by Si Surface Flattening of Electrical Characteristics in MOSFETs With High-k HfON Gate Insulator
Author :
Ohmi, Shun-ichiro ; Kudoh, Sohya ; Atthi, Nithi
Author_Institution :
Dept. of Electron. & Appl. Phys., Tokyo Inst. of Technol., Yokohama, Japan
Abstract :
Variability improvement of metal-oxide-semiconductor field-effect transistors (MOSFETs) characteristics with high-k HfON gate insulator by Si surface flattening was investigated. The Si surface flattening process was carried out by Ar/4.9%H2 anneal utilizing rapid thermal annealing system. The HfON gate insulator was formed by the in-situ Ar/O2 plasma oxidation of HfN utilizing electron cyclotron resonance plasma sputtering followed by the post deposition anneal at 600 °C for 1 min. The Si surface flattening was found to significantly improve the threshold voltage variability (ΔVTH) of MOSFET with HfON gate insulator for the first time. Furthermore, the stability of the device characteristics was improved up to the measurement temperature of 100 °C by introducing the Si surface flattening process.
Keywords :
MOSFET; cyclotron resonance; hafnium compounds; insulators; oxidation; rapid thermal annealing; silicon; sputtering; HfON; MOSFET; Si; electrical characteristic; electron cyclotron resonance; high-k gate insulator; metal-oxide semiconductor field-effect transistor; plasma oxidation; plasma sputtering; post deposition anneal; rapid thermal annealing system; silicon surface flattening; temperature 100 C; temperature 600 C; threshold voltage variability; variability improvement; Annealing; Hafnium compounds; Logic gates; MOSFET; Silicon; Surface treatment; Temperature measurement; ECR plasma sputtering; Electron cyclotron resonance (ECR) plasma sputtering; HfON; MOSFETs; Si surface flattening; gate insulator; high-k; metal-oxide-semiconductor field-effect transistors (MOSFETs); variability;
Journal_Title :
Semiconductor Manufacturing, IEEE Transactions on
DOI :
10.1109/TSM.2015.2431375
