Title :
Observation of nitrogen-enhanced doping deactivation at the polysilicon-oxynitride interface of pMOSFETs with 12-/spl Aring/ gate dielectrics
Author :
Ahmed, Khaled Z. ; Kraus, Philip A. ; Olsen, Chris ; Hung, Steven ; Nouri, Faran
Author_Institution :
Transistor Syst. Group, Appl. Mater. Inc., Santa Clara, CA, USA
fDate :
7/1/2003 12:00:00 AM
Abstract :
This letter reports the observation of a process integration issue that arises when large doses of nitrogen (>1/spl times/10/sup 15/ cm/sup -2/) are incorporated in oxynitride gate dielectric films targeting equivalent oxide thickness of 11-13 /spl Aring/. It is shown that capacitance-extracted active doping density at the polysilicon/oxynitride (poly/SiON) interface of boron-doped p/sup +/-polysilicon gated pMOSFETs decreases with increasing nitrogen dose of the oxynitride film as measured by X-ray photoelectron spectroscopy. A physical mechanism is proposed to explain experimental observations.
Keywords :
MOSFET; X-ray photoelectron spectra; semiconductor doping; 12 /spl Aring/; Si:B-SiON; X-ray photoelectron spectroscopy; active doping density; boron-doped p+-polysilicon gate; capacitance; equivalent oxide thickness; high-/spl kappa/ material; nitrogen-enhanced doping deactivation; oxynitride gate dielectric film; pMOSFET; polysilicon-oxynitride interface; process integration; CMOS technology; Capacitance measurement; Dielectric materials; Dielectric measurements; Doping; MOS devices; MOSFETs; Nitrogen; Plasma devices; Plasma measurements;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2003.814022