کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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5369585 | 1388443 | 2007 | 5 صفحه PDF | دانلود رایگان |
Hf1âxSixOy is an attractive candidate material for high-k dielectrics. We report in this work the deposition of ultra-thin Hf1âxSixOy films (0.1 â¤Â x â¥Â 0.6) on silicon substrate at 450 °C by UV-photo-induced chemical vapour deposition (UV-CVD) using 222 nm excimer lamps. Silicon(IV) and hafnium(IV) organic compounds were used as the precursors. Films from around 5 to 40 nm in thickness with refractive indices from 1.782 to 1.870 were grown. The deposition rate was found to be of 6 nm/min at a temperature of 450 °C. The physical, interfacial and electrical properties of hafnium silicate (Hf1âxSixOy) thin films were investigated by using X-ray photoelectron spectroscopy, ellipsometry, FT-IR, C-V and I-V measurements. XRD showed that they were basically amorphous, while Fourier transform infrared spectroscopy (FT-IR), clearly revealed Hf-O-Si absorption in the photo-CVD deposited Hf1âxSixOy films. Surface and interfacial properties were analysed by TEM and XPS. It is found that carbon content in the films deposited by UV-CVD is very low and it also decreases with increasing Si/(Si + Hf) ratio, as low as about 1 at.% at the Si/(Si + Hf) ratio of 60 at.%.
Journal: Applied Surface Science - Volume 253, Issue 19, 31 July 2007, Pages 7869-7873