Characteristics of high quality hafnium oxide gate dielectric

N. Zhan1, K.L. Ng1, M.C. Poon1, C.W. Kok1, M. Chan1, H. Wong2
1Department of Electrical and Electronic Engineering, Hong Kong University of Science and Technology, Hong Kong, China
2City University of Hong Kong, Kowloon Tong, Hong Kong, China

Tóm tắt

Hafnium oxide (HfO/sub 2/) was investigated as an alternative possible gate dielectric. A MOS capacitor using HfO/sub 2/ as dielectric was fabricated and studied. The HfO/sub 2/ film was formed by direct sputtering of Hf in O/sub 2/ and Ar ambient on to a Si substrate and post-sputtering rapid thermal annealing (RTA). XPS results showed that the interface layer formed between the HfO/sub 2/ and the Si substrate was affected by the RTA time within the 500/spl deg/C to 600/spl deg/C annealing temperature. The interface layer was mainly composed of hafnium silicate and had high interface trap density. Increase in RTA time was found to lower the effective barrier height of the layer and the FN tunneling current.

Từ khóa

#Hafnium oxide #Dielectric substrates #Rapid thermal annealing #Leakage current #Bonding #Sputtering #Temperature #High K dielectric materials #Capacitors #Chemicals

Tài liệu tham khảo

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