Title :
Substituted aluminum metal gate on high-k dielectric for low work-function and Fermi-level pinning free
Author :
Park, Chang Seo ; Cho, Byung Jin ; Tang, Lei Jun ; Kwong, Dim-Lee
Author_Institution :
Silicon Nano Device Lab., Dept. of Electr. & Comput. Eng., Singapore National University, Singapore
Abstract :
Substituted aluminum (SA) metal gate on high-K gate dielectric is successfully demonstrated. Full substitution of polysilicon with Al is achieved in Ti/Al/polysilicon/HfAlON gate structure by a low temperature annealing at 450°C. The SA gate on HfAlON dielectric shows a very low work function of 4.25 eV, which is well suitable for bulk nMOSFETs. The SA process is fully free from Fermi level pinning problem. In addition, the SA process also shows improved uniformity in leakage current distribution compared to fully silicided (FUSI) metal gate.
Keywords :
Fermi level; MOSFET; aluminium; annealing; dielectric materials; silicon; work function; 4.25 eV; 450 C; Fermi level pinning; Si-HfAlON; Ti; fully silicided metal gate; gate structure; high-k dielectric; leakage current distribution; nMOSFET; substituted aluminum metal gate; temperature annealing; work function; Aluminum; Annealing; Artificial intelligence; Capacitance-voltage characteristics; Doping; Furnaces; High-K gate dielectrics; MOSFET circuits; Silicon; Temperature;
Conference_Titel :
Electron Devices Meeting, 2004. IEDM Technical Digest. IEEE International
Print_ISBN :
0-7803-8684-1
DOI :
10.1109/IEDM.2004.1419138
