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Amorphous silicon oxynitride (a-SiN[sub x]O[sub y]) films were deposited at 300 °C using a plasma-enhanced chemical vapor deposition technique, which was carried out with variation in the nitrogen-flow-rate ratio (R[sub N]) and the oxygen-flow-rate ratio (R[sub O]) to control the nitrogen and oxygen contents, x and y, respectively. Changes in the structural properties and the characteristics of defects in the films were examined based on the electron spin resonance as well as infrared and optical absorption measurements. An increase in either R[sub N] or R[sub O] was found to decrease the deposition rate, the density of charged or neutral defects, and the randomness of the bonding network. Thus the incorporation of O or N atoms into Si nitride or Si oxide films, respectively, acts to improve the qualities of the insulating films. Furthermore, the nearest N and O atom neighboring to a Si site would be randomly bonded to the Si atom. Our results also showed that N-related dangling bonds, other than so-called K centers, are favorably created after annealing, but that the formation of Si-O bonds in the films makes the formation of such defects difficult. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Presents a study which examined the bonding properties of glow discharge polycrystalline and amorphous silicon carbide films. Correlation of the growth mechanism and the effects of hydrogen dilution with changes in bonding configuration; Experimental procedure; Results and discussion.

Presents a study that investigated the effects of the incorporation of phosphorus and nitrogen impurities on the electrical and structural properties of polysilicon carbide thin films. Methodology; Examination of the resistivity and spin density of the samples; Analysis of the crystallinity of the samples.

Presents a study that prepared undoped polycrystalline silicon films on a fused quartz substrate as a function of the radio frequency power and deposition temperature by a plasma-enhanced chemical vapor deposition method. Details of the experiment; Results and discussion; Conclusion.

Presents a study of the crystal structure and the bonding configurations of Si[sub1-x]C[subx] films prepared by plasma-enhanced chemical vapor deposition. Description of cubic silicon carbide; X-ray diffraction pattern on the films; Classification of films according to the composition.

In this letter, polycrystalline 3C-SiC (111) films were deposited by plasma enhanced chemical vapor deposition system at a temperature of 670 °C using a gas mixture of SiH4/CH4/H2/(CF4). The optical properties of deposited films with different feed gases and different structures were investigated. In these studies, a broad photoluminescence band was observed for films with lower crystallinity and the radiative transitions between the conduction and valance band tails were suggested as the origin of the observed peak. The band gap of these polycrystalline SiC films was estimated at around 2.10 eV. [ABSTRACT FROM AUTHOR]

Investigates the vibrational absorption of silicon hydride in amorphous SiO[sub x]:H film based on the charge-transfer model. Examination of absorption profiles on the basis of random-bonding model; Use of Sanderson's electronegativity to study the length of hydride bonds; Details on the peak wave numbers for the four hydrogen-silicon bonding units.

Amorphous SiNx:H films were prepared by rf glow discharge (GD) of SiH4-N2-H2 mixtures at 300 °C using a new decomposition technique. The optical gap Eg increases slowly with the ratio N2/SiH4 up to a critical gap Egc of 2.5–3.0 eV, and then rapidly increases up to 5.3 eV. The spin density Ns from electron spin resonance of Si dangling bonds increases with N2/SiH4 until Eg reaches Egc. Above Egc, Ns rapidly decreases in contrast with that of conventional GD films, but in similarity to pyrolytic films. The slope B in Tauc equation for optical absorption corresponds well with Ns. [ABSTRACT FROM AUTHOR]

Investigates the bonding configuration and defects in amorphous SiN[sub x]:H films. Maximum of the slope in the Urbach form of the absorption coefficient; Examination of the random-bonding model including hydrogen atoms.

Polycrystalline silicon (poly-Si) films were prepared on a fused quartz substrate at 700 °C by low-pressure chemical vapor deposition (LPCVD) and plasma-enhanced CVD (PECVD) using the same fabrication system. Poly-Si films with a strong <100> and <110> preferential orientation (P.O.) are obtained by changing the rf power for generating the plasma under the same preparation condition. The surface of the PECVD films with dominant <100> and <110> textures is very smooth in contrast with that of LPCVD films. These textures are maintained after thermal oxidation at 1000 °C, and the degree of P.O. and the grain size increase. [ABSTRACT FROM AUTHOR]

Examines the structure of polycrystalline silicon (poly-Si) films made by the annealing of amorphous silicon films deposited using disilane. Function of deposition temperature in the preparation of poly-Si thin films; Change in the texture of poly-Si films; Influence of amorphous Si films deposition change on texture and grain size.

Abstract: The structural properties of polycrystalline silicon films, prepared by plasma enhanced chemical vapor deposition system, with different flow rates of SiH4/SiF4 mixtures at 300°C were investigated. This study indicates that the low hydrogen coverage on the growing surface, under optimum fluorine radicals, will be leaded to an improvement of crystallized area as compared with case of high hydrogen coverage surface. Moreover, the studies of the role of SiH4 and SiF4 radicals show that the SiH4 radicals are important in the nucleation and growth of grains. However, SiF4 radicals are effective in the structural change of grain boundaries regions and by this way, in the present system, establish the growth of grains under the dominant 〈110〉 direction. The stress investigation indicates that addition of high flow rate of SiF4 in amorphous film, results in the nearly stress free films. Finally, we found that the changes in g-value reflect the changes in the intrinsic compressive and tensile stress in the both polycrystalline and amorphous silicon films. [Copyright &y& Elsevier]

Abstract: The structural properties of polycrystalline silicon films, prepared by plasma enhanced chemical vapor deposition system, with different flow rates of SiH4/SiF4 mixtures at 300°C were investigated. This study indicates that the low hydrogen coverage on the growing surface, under optimum fluorine radicals, will be leaded to an improvement of crystallized area as compared with case of high hydrogen coverage surface. Moreover, the studies of the role of SiH4 and SiF4 radicals show that the SiH4 radicals are important in the nucleation and growth of grains. However, SiF4 radicals are effective in the structural change of grain boundaries regions and by this way, in the present system, establish the growth of grains under the dominant 〈110〉 direction. The stress investigation indicates that addition of high flow rate of SiF4 in amorphous film, results in the nearly stress free films. Finally, we found that the changes in g-value reflect the changes in the intrinsic compressive and tensile stress in the both polycrystalline and amorphous silicon films. [Copyright &y& Elsevier]

Amorphous Si oxynitride (a-SiOxNy) films were deposited at 300 °C using a plasma-enhanced chemical vapor deposition technique, by varying the NH3 flow rate, [NH3], under fixed SiH4 and O2 flow rates to control the x- and y-values. The characteristics of defects were investigated vis-a&grave;-vis structural and bonding properties. These films were ‘stoichiometric’, including no or less homobonds. As [NH3] increases, the x- and y-values decreased and increased, respectively, and a relationship of 2x+3y=4.14 (±0.02) was found. With increasing [NH3], the deposition rate increased, but the defect density and the stress can be decreased. [Copyright &y& Elsevier]