In Situ Removal of Native Oxides from Silicon Surfaces Using Anhydrous Hydrogen Fluoride Gas

1999 ◽  
Vol 1 (2) ◽  
pp. 77 ◽  
Author(s):  
Heungsoo Park
1993 ◽  
Vol 318 ◽  
Author(s):  
Pushkar P. Apte ◽  
Heungsoo Park ◽  
Krishna C. Saraswat ◽  
C. R. Helms

ABSTRACTIn-situ native-oxide removal is critical for epitaxial single-crystal silicon deposition, for polysilicon emitters and contacts and for ultrathin gate dielectric films in integrated circuit (IC) fabrication. We have developed an in-situ, thermally-driven, anhydrous hydrogen fluoride (AHF)-based native-oxide removal technique in which the wafer is treated by AHF at low temperatures (300-400°C) and a short (10 sec) 950°C ‘spike’ in AHF-H2 immediately prior to Si deposition. This process removes native oxides formed by standard wet cleans such as HC1:H202 and NH4OH:H202, as well as native oxides formed by the clean-room ambient. Further, the technique is an effective pre-clean for both polysilicon and epitaxial silicon deposition. This flexibility, combined with other salient features such as simplicity and a low thermal budget, make the process eminently suited for IC fabrication.


Vacuum ◽  
1995 ◽  
Vol 46 (7) ◽  
pp. 667-672 ◽  
Author(s):  
A Crossley ◽  
C.J. Sofield ◽  
S Sugden ◽  
R Clampitt ◽  
C Bradley

1999 ◽  
Vol 567 ◽  
Author(s):  
Masayuki Suzuki ◽  
Yoji Saito

ABSTRACTWe tried direct oxynitridation of silicon surfaces by remote-plasma-exited nitrogen and oxygen gaseous mixtures at 700°C in a high vacuum. The oxynitrided surfaces were investigated with in-situ X-ray photoelectron spectroscopy. With increase of the oxynitridation time, the surface density of nitrogen gradually increases, but that of oxygen shows nearly saturation behavior after the rapid increase in the initial stage. We also annealed the grown oxynitride and oxide films to investigate the role of the contained nitrogen. The desorption rate of oxygen from the oxynitride films is much less than that from oxide films. We confirmed that nitrogen stabilizes the thermal stability of these oxynitride films.


Sign in / Sign up

Export Citation Format

Share Document