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The electrical properties of silicon nanocrystals (Si NCs) embedded in silicon-rich silicon nitride (SRSN) films were investigated by fabricating metal-insulator-semiconductor capacitor structures to utilize the Si NCs as charge storage nodes. The Si NCs embedded in SRSN films were prepared by catalytic chemical vapor deposition technique at substrate temperatures below 200 °. The counterclockwise hysteresis loops were observed in capacitance-voltage (C-V) characteristics. A memory window of 13 V was observed in the sweep voltage range of ±12 V.

We studied the effect of in-situ hydrogen annealing on dielectric SiNx films at a low-temperature (150 oC) by Cat-CVD. The in-situ hydrogen annealing was performed without a vacuum breaking. After in-situ annealing, furnace annealing was performed for 2hours below 150 oC. The C-V, and I-V characteristics were measured by MIS structure. The high hydrogen ratio sample showed better dielectric properties improvement by annealing. SiNx films dielectric properties were extremely improved by in-situ hydrogen annealing and furnace annealing. Breakdown field was 6 MV/cm. C-V hysteresis window was reduced from 15 V to 1 V. The on/off ratio of TFT was 105. The Mobility was 0.23. We successfully fabricated dielectric SiNx films at the low temperature, and also a-Si TFTs at the same temperature by Cat-CVD.

The dielectric property has great influence on characteristics of bottom-gate nanocrystalline silicon thin film transistor at low process temperature ({less than or equal to} 200°). For improving the quality of the gate dielectric layer, in-situ hydrogen annealing step in the silicon nitride deposition process was attempted in low process temperature by catalytic CVD system. The in-situ hydrogen annealing was effective in advanced field effect mobility and capacitance-voltage characteristic by decreasing the defects inside the SiNx film.

Si/SiC composite films, namely, Si nanocrystals in a-SiC matrix material, were deposited by using Cat-CVD. Photoluminescence characteristics of a-SiC thin films prepared with various gas ratio R=[CH4]/[SiH4] were investigated. Fourier-transform infrared spectroscopy (FTIR) and x-ray photoelectron spectroscopy (XPS) measurements composition ratio of a-SiC films. It shows different composition ratio between R > 10 and R < 10. Photoluminescence (PL) intensity was changed before and after thermal annealing at various temperatures. The PL intensity was increased after annealing peak position was shift short wavelength range.

The silicon nanocrystals embedded in silicon-rich silicon nitride films were deposited by catalytic CVD at low temperature (≤200 °C). Excimer laser annealing and in-Situ H2 treatment were performed to increase quantum efficiency. Electrical properties of metal-insulator-semiconductor structures using these samples were measured.

The nanocrystalline silicon bottom-gate thin film transistor (nc-si TFT) should improve on formed amorphous incubation layers at the onset of deposition because these layers deteriorate the performance of the transistor. We attempted modulation of hydrogen dilution ratio to achieve both the minimal incubation layer and high deposition rate. The incubation layer thickness was estimated by transmission electron microscopy (TEM) and crystallization fraction was measured by Raman spectroscopy.