DocumentCode :
3511233
Title :
Suppression of thermal interface degradation in high-k film/Si by helium
Author :
Muraoka, Kouichi
Author_Institution :
Adv. LSI Technol. Lab., Toshiba Corp., Yokohama
fYear :
2005
fDate :
4-7 Oct. 2005
Abstract :
Suppression of thermal interface degradation, especially silicidation, in high-k film (ZrO2, HfO2)/Si systems by a helium (He) process, which adds He gas during various annealing processes, was demonstrated. The high-k film/SiO2/Si thermal interface stability was investigated in terms of N2, and He gas annealing with controlled oxygen partial pressure (PO2) at 920degC. A comparison of N2 and He annealing with controlled PO2 revealed that the optimal PO2 ranges in He at which the thermal stability of a layered structure can be achieved are wider than that in N2. Moreover, regarding the poly-Si/SiO2/high-k film interface, it was found that He through process consisting of low-temperature SiH 4 flow diluted by He and high-pressure He post-annealing is the most effective means of suppressing silicidation, whereas a conventional N2 through process cannot. These results indicate that high-concentration He atoms are indispensable for the upper poly-Si/SiO2 interface. It is supposed that many He atoms physically obstruct SiO creation through the quenching of atomic vibration at the SiO2/Si interface, thus impeding the first step of the silicidation reaction
Keywords :
annealing; chemical vapour deposition; elemental semiconductors; hafnium compounds; high-k dielectric thin films; interface phenomena; semiconductor thin films; semiconductor-insulator boundaries; silicon; silicon compounds; thermal stability; zirconium compounds; 920 degC; He annealing; HfO2-SiO2-Si; N2 annealing; ZrO2-SiO2-Si; atomic vibration quenching; chemical vapor deposition; helium process; high-k film/Si systems; high-pressure He post-annealing; low-temperature SiH4 flow; silicidation; thermal interface degradation suppression; thermal interface stability; Annealing; Hafnium oxide; Helium; High K dielectric materials; High-K gate dielectrics; Pressure control; Semiconductor films; Silicidation; Thermal degradation; Thermal stability;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Advanced Thermal Processing of Semiconductors, 2005. RTP 2005. 13th IEEE International Conference on
Conference_Location :
Santa Barbara, CA
Print_ISBN :
0-7803-9223-X
Type :
conf
DOI :
10.1109/RTP.2005.1613682
Filename :
1613682
Link To Document :
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