THERMALLY-OXIDIZED HfO{sub}2 ON Se-PASSIVATED n-TYPE Si(100)

摘要

Se passivation of Si(100) creates a surface which is free of dangling bonds. Electrically, the passivation may also result in a surface free of surface states. It is interesting to examine the effect of Se passivation on the electrical properties of the high-k dielectric/Si(100) interface. In this paper, we report our results on interface engineering between HfO{sub}2 and n-type Si(100) with Se passivation. Hf of ～40 A was deposited on Se-passivated Si(100) by e-beam evaporation and then oxidized in O{sub}3 or O{sub}2 to form HfO{sub}2. I-V and C-V characterization was performed to examine the electrical properties of the HfO{sub}2/Se/Si(100) interface. O{sub}3 oxidation seems to over-oxidize into the n-type Si substrate, causing a large negative shift in flat-band voltage. Samples annealed in O{sub}2 below ～350°C show much improved properties: a smaller EOT, a flat-band voltage close to the theoretical value, and a smaller leakage current. Our results also demonstrate that Se passivation of Si(100) suppresses Si oxidation in O{sub}2 up to 600°C.