DocumentCode :
2265350
Title :
Etching of HfO2, deposited on LPCVD Si3N4, and cleaning of Hf residues
Author :
Kraus, H. ; Snow, Juna ; Van Doorne, P. ; Mertens, P.W. ; Kovacs, F.
Author_Institution :
IMEC, Leuven, Belgium
fYear :
2003
fDate :
30 Sept.-2 Oct. 2003
Firstpage :
221
Lastpage :
224
Abstract :
In FEOL silicon nitride is often deposited on the backside of the wafer before the high-k deposition, because it offers some advantages, such as avoiding damage of the Si surface during removal of the gate material from the backside of the wafer. In order to prevent cross contamination in shared tools the backside has to be cleaned from remaining high-k contamination. This work indicates that the etching of HfO2 is affected by the Post Deposition Anneal condition and also by the underlying silicon nitride. Furthermore the etching behavior of silicon nitride is different from the usual etch characteristics of a LPCVD Si3N4. This, and additionally Hf contamination inside the Si3N4 layer, even down to the Si-Si3N4 interface, and the difficulty to clean Hf contamination at the Si-Si3N4 interface lead to the conclusion that the backside clean of Hf contamination is not a straightforward process.
Keywords :
CVD coatings; annealing; etching; hafnium compounds; semiconductor technology; silicon compounds; surface cleaning; surface contamination; wide band gap semiconductors; FEOL silicon nitride; Hf residues; HfO2; HfO2 etching; LPCVD Si3N4; Si surface; Si-Si3N4 interface; Si3N4-Si; cleaning; cross contamination; gate material; high dielectric deposition; post deposition annealing; silicon nitride compound; wafer; Annealing; Cleaning; Contamination; Etching; Hafnium oxide; High K dielectric materials; High-K gate dielectrics; Silicon; Temperature; Thickness measurement;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Semiconductor Manufacturing, 2003 IEEE International Symposium on
ISSN :
1523-553X
Print_ISBN :
0-7803-7894-6
Type :
conf
DOI :
10.1109/ISSM.2003.1243269
Filename :
1243269
Link To Document :
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