Title :
Nitrogen Incorporation in HfSiO(N)/TaN Gate Stacks: Impact on Performances and NBTI
Author :
Aoulaiche, Marc ; Houssa, M. ; Deweerd, W. ; Trojman, L. ; Conard, T. ; Maes, J.W. ; De Gendt, S. ; Groeseneken, Guido ; Maes, Herman E. ; Heyns, M.M.
Author_Institution :
Interuniv. Microelectron. Center, Leuven
fDate :
7/1/2007 12:00:00 AM
Abstract :
Performance and negative-bias temperature instability (NBTI) on atomic-layer-deposited HfSiON metal-gated pMOSFETs are investigated. The impact of nitrogen incorporation either with plasma nitridation or NH3 anneal is studied and compared to the nonnitrided stacks. The capacitance equivalent thickness reduction that is observed in nitrided stacks is compensated by the slight decrease of the hole mobility for the same gate overdrive, resulting in no improvement of the performance. On the other hand, it is shown that nitridation strongly enhances NBTIs in these devices. Based on these results, the necessity of nitrogen incorporation in thin HfSiON/metal gate stacks should be reconsidered.
Keywords :
MOSFET; ammonia; annealing; atomic layer deposition; carrier mobility; hafnium compounds; nitridation; nitrogen; plasma materials processing; tantalum compounds; thermal stability; HfSiON-TaN - Interface; NH3 - Binary; annealing; atomic-layer-deposited HfSiON metal-gated pMOSFET; capacitance equivalent thickness reduction; hole mobility; negative-bias temperature instability; nitrogen incorporation; nonnitrided stacks comparison; plasma nitridation; Annealing; Capacitance; MOSFETs; Microelectronics; Niobium compounds; Nitrogen; Personal digital assistants; Plasma chemistry; Plasma temperature; Titanium compounds; Gate devices; high-$kappa$; negative-bias temperature instability (NBTI); nitrogen; transistor performance;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2007.899435
