This work presents a reliable method of growing aggressively scaled, 1.0 nm thick, gate dielectric in mixtures of N 2 and O 2 ambient at 900°C for 15 s by rapid thermal processing ͑RTP͒. These oxynitride films have excellent interface properties, 100 times lower leakage current density, and better charge trapping properties than rapid thermal oxidation SiO 2 of identical thickness prepared in pure O 2 ambient. The effect of interfacial nitrogen concentration on the device characteristics with gate oxynitride films grown in various N 2 /O 2 gas flow ratios was also investigated. The results demonstrate that the uniform nitrogen content increases with the N 2 /O 2 gas flow ratio and that high-quality oxynitride films can be obtained by RTP in an optimum gas flow ratio of N 2 /O 2 ϭ 5/1 (slm).Highly reliable and aggressively scaled gate dielectric films ͓equivalent oxide thickness (EOT р 1 nm͔ are essential for developing complementary metal-oxide semiconductor ͑CMOS͒ technologies beyond the sub-0.1 m regime. However, when the thickness of SiO 2 is reduced below 2 nm, the primary concerns in the use of ultrathin oxides are gate leakage and device reliability. 1 Accordingly, the use of alternative gate dielectrics must be considered. The formation of ultrathin oxynitride gate dielectric using a nitrogencontaining gas ͑such as N 2 O or NO͒ to improve the leakage current, reliability, and superior resistance to boron penetration have been examined extensively. 2,3 However, as the oxynitride thickness continues to be reduced to the 1.0 nm regime, the maximum nitrogen concentration that can be incorporated by the aforementioned processes decreases and the oxynitride film becomes leaky and no longer reliable. 4 Although NH 3 -nitrided SiO 2 films can be used effectively to increase the concentration of incorporated N atoms, increased fixed charge and interface trap densities are unavoidable due to electron trap related N-H bonds introduced from NH 3 . 5,6 An oxynitride growth process that can provide nitrogen-rich oxynitride films, is required to improve electrical characteristics and thus solve these problems and achieve an ultrathin oxynitride film (EOT ϭ 1.0 nm) with more incorporated nitrogen. This paper develops a new technique for fabricating nitrogen-rich ultrathin oxynitride films down to physical thickness 1.0 nm by rapid thermal processing ͑RTP͒ in a high N 2 /O 2 gas flow ratio ambient ͓rapid thermal nitrided oxide ͑RTNO͔͒. The optimum growth conditions and electrical characteristics of oxynitride dielectric by RTNO are also demonstrated. ExperimentalMOS capacitors with high quality 1.0 nm thick oxynitride films were fabricated using a compatible 0.13 m CMOS processing technology. The 3-5 ⍀-cm n-type silicon ͑100͒ wafers were cleaned using piranha (H 2 SO 4 :H 2 O 2 ϭ 5:1) solution for 10 min, and then thoroughly rinsed in deionized ͑DI͒ water. The wafers were then washed in 1% HF acid immediately before the dielectric film was grown. The 1.0 nm thick gate oxynitride films were grown by RTP at various N 2 /O 2 ...

Increasing the fraction of Ge in SiGe-on-insulator (SGOI) using Ge condensation by oxidation significantly increases hole mobility. This effect can be exploited to improve the sensitivity of SGOI nanowire. However, our previous studies found that the sensitivity of an SGOI nanowire is degraded as the Ge fraction increases over 20%, because of the surface state of SiGe is unstable when the Ge fraction is high. In this work, a top surface passtivation Si02 layer was deposited on an Sio.8Geo.2 nanowire and successfully improve its sensitivity around 1.3 times that of the nanowire sample without top a passivation layer.

Increasing the fraction of Ge in SiGe-on-Insulator (SGOI) using Ge condensation by oxidation significantly increases hole mobility. This effect can be exploited to improve the sensitivity of SGOI nanowire. However, our previous studies found that the sensitivity of an SGOI nanowire is degraded as the Ge fraction increases over 20%, because of the surface state of SiGe is unstable when the Ge fraction is high. In this work, a top surface passtivation SiO2 layer was deposited on an Si 0.8 Ge 0.2 nanowire and successfully improve its sensitivity around 2.5 times that of the nanowire sample without top a passivation layer.

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Nanowires are widely used as highly sensitive sensors for electrical detection of biological and chemical species. Modifying the band structure of strained-Si metal-oxide-semiconductor field-effect transistors by applying the in-plane tensile strain reportedly improves electron and hole mobility. The oxidation-induced Ge condensation increases the Ge fraction in a SiGe-on-insulator (SGOI) and substantially increases hole mobility. However, oxidation increases the number of surface states, resulting in hole mobility degradation. In this work, 3-aminopropyltrimethoxysilane (APTMS) was used as a biochemical reagent. The hydroxyl molecule on the oxide surface was replaced by the methoxy groups of the APTMS molecule. We proposed a surface plasma treatment to improve the electrical properties of SiGe nanowires. Fluorine plasma treatment can result in enhanced rates of thermal oxidation and speed up the formation of a self-passivation oxide layer. Like a capping oxide layer, the self-passivation oxide layer reduces the rate of follow-up oxidation. Preoxidation treatment also improved the sensitivity of SiGe nanowires because the Si-F binding was held at a more stable interface state compared to bare nanowire on the SiGe surface. Additionally, the sensitivity can be further improved by either the N2 plasma posttreatment or the low-temperature postannealing due to the suppression of outdiffusion of Ge and F atoms from the SiGe nanowire surface.