Crystalline SiC samples were prepared in solidification of silicon melt saturated by carbon solved from the inner wall of a graphite crucible. The crystalline structure of the samples was analysed in Raman spectroscopy and confirmed as 3C-SiC both in x-ray diffraction and x-ray photoelectron spectroscopy (XPS). The Raman spectra of the samples present a strong sharp peak located at 796.3cm-1 with a full width at half maximum about 6cm-1 and three weak peaks broadened around 1525.6, 1631.4 and 1719.1cm-1, respectively. The former belongs to the transverse optical phonons of 3C-SiC, while the latter can be attributed to the second-order scattering. However, the longitudinal optical mode of 3C SiC has not been found for our samples. An additional broadened peak at 532.2 cm-1 may imply the existence of some lattice defect in the samples, which is related to nitrogen introduced unintentionally into the lattice in the growth process and confirmed in XPS of N 1s binding energy centred at 400.9 eV.

A novel technique has been developed to lithographically make fine patterns on PZT films. Employing chemical modification in acetylacetone (AcAc), we have obtained an UV photosensitive PZT sol from which the PZT films to be patterned can be prepared. With methanol as solvent and AcAc as chemical modifier, three sols used to compose the PZT coating sol are obtained from Zirconium oxynitrate (ZrO(NO3)2), lead acetate (Pb (CH3COO)2), and tetrabutyl titanate ((C4H9O)4Ti), respectively. By means of UV-vis and FT-IR spectrophotometers we have found that AcAc can associate with Zr, Pb, and Ti ions to form three chelate complexes, the UV absorption peaks of which are located at wavelength 304, 315 and 329 nm, respectively. However, the photosensitive PZT coating sol has UV absorption peak at around 312 nm. Both the chelate complexes in sol and the UV absorption peak can be remained in the gel films. When the photosensitive PZT gel film is irradiated by UV light containing 312 nm wavelength, its solubility in solvents such as alcohol, acetone and so on is reduced remarkably, while the UV absorption peak disappears with the dissociation of the chelate complexes correspondingly. Utilizing the characteristics, a fine pattern can be obtained by irradiation of UV light on the PZT gel film through a pattern mask and dissolving the non-irradiated area in suitable solvent. After annealing at 680

Intense wide-band photoluminescence (PL) with high stability to ultraviolet (UV) light irradiation has been observed in a wide temperature range from a polycrystalline SiC sintered from graphite and melt Si at high temperature over 1500

Intense photoluminescence (PL) from porous-like SiC has been observed at room temperature. The samples were prepared by electrochemical anodization from nanocrystalline SiC thin films grown on Si (100) substrates in hot filament chemical vapor deposition. It has been found that a light-induced enhancement of the PL intensity will take place if the incident light beam from an He-Cd laser (325nm, 10mW) is employed for the excitation. Blue-shift of the PL peak energy from about 1.9 eV of as-anodized samples to about 2.1 eV and an accompanied spectral widening have also been observed for a long enough irradiation time. However, the novel effects have not been observed at low temperature. Origin of the light-induced change is suggested to be related to some light-induced metastable defects.

In this paper, we present a novel method to grow 3C-SiC crystal in a liquid-phase epitaxy-like manner, but without any substantial substrate. The starting material to be used in this method is the 3C-SiC-thin film deposited on Si substrate in a gas-phase heteroepitaxial technology. The free 3C-SiC film which remained of the molten Si substrate epitaxially grows up from the Si solution saturated by SiC in a highly purified graphite crucible heated by an inductive heater. XRD, XPS and Raman spectroscopy were used to characterize the samples. The only one peak with full width at half maximum (FWHM) of 0.2 at 20 = 35.65