THE ANNEALING EFFECT OF CRYSTAL 4H-SiC FILMS PREPARED BY PULSED LASER DEPOSITION
Wang Yu-xia (王玉霞)a, Wen Jun (温军)a, Tang Ye-qing (汤业庆)a, Guo Zhen (郭震)a, Tang Hong-gao (汤洪高)a, Wu Jian-xin (吴建新)b
a Department of Material Science and Engineering, University of Science and Technology of China, Hefei 230026, China; b Structure and Element Analysis Center, University of Science and Technology of China, Hefei 230026, China
Abstract SiC films were prepared by pulsed XeCl laser ablation of ceramic SiC target on Si(100) substrate at temperature 850℃ and post-deposition high temperature annealing above 1100℃ (1100℃ < T < 1400℃) in high vacuum (1.3 $\times$ 10-7 Pa). The surface morphology, crystal structure, composition and chemical state of the element in the films before and after annealing were studied by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, Auger electron Spectrum, X-ray photoelectron spectrum and photoluminescence methods. It was found that the films were consisted of polycrystal 4H-SiC structure before annealing and were turned into singlecrystal epitaxial 4H-SiC after annealing. The surfaces of the films were smooth and the adhesion of films with the substrate was good. The films were transparent. Excited by the laser with wavelength 290 nm at room temperature, the films emitted two luminescence bands with the peaks at 377 nm and 560 nm. The emission at 377 nm was attributed to the combination of the transmission among the valence and conductor bands, while the one at 560 nm was possibly to be from exciton emission.
Received: 10 November 1997
Revised: 18 March 1998
Accepted manuscript online:
Altmetric calculates a score based on the online attention an article receives. Each coloured thread in the circle represents a different type of online attention. The number in the centre is the Altmetric score. Social media and mainstream news media are the main sources that calculate the score. Reference managers such as Mendeley are also tracked but do not contribute to the score. Older articles often score higher because they have had more time to get noticed. To account for this, Altmetric has included the context data for other articles of a similar age.