采用溶胶-凝胶法制备nc-Si/SiO_2薄膜

Preparation of nc-Si/SiO_2 Film with Sol-gel Method

溶胶 凝胶方法是近年发展起来的一种新型的材料制备技术,被广泛的应用于薄膜、均匀超细粉末和陶瓷涂层的制备中。本文以正硅酸乙酯(TEOS)为原料,在乙醇共溶剂和盐酸催化剂条件下,采用溶胶 凝胶方法制备含有纳米晶硅(nc Si)的SiO2胶体溶液,通过旋涂法使溶剂迅速挥发而迅速凝胶化,经过适当温度的干燥和烧结制备了nc Si/SiO2薄膜。探讨了胶体粘度、盐酸催化剂浓度、旋涂速度和时间对成膜质量的影响。给出了nc Si/SiO2薄膜的扫描电镜图像和表征nc Si/SiO2薄膜组分的能谱图。

Semiconducting silicon is the dominant material in microeletronics, which is a key for high technology, but it cannot emit light efficiently. It is necessary to develop Sibased light emitting material for optoelectronic integrational device.The study of Sibased light emitting materials is a new leading field in semiconductor optoelectronics and photonics. Bulk Si, however, is of little use for photonic devices owing to its indirect band gap and its poor radiative electronhole recombination.The light emitting of Sibased quantumdot is attractive research direction. The ncSi(Si quantumdot)/SiO2 is a promising light emitting material. The quantum confinement effect in nanocrystallites has proved to be highly effective for light emission.In this paper, the tetraethoxysilane (TEOS) precursor is hydrolyzed with ethanol as cosolvent under various concentrations of hydrochloric acid catalyzer to prepare the SiO2 solution through solgel process.A ncSi/SiO2 film were fabricated by spincoating of such prepolymer solutions onto glass slides followed by aging and during of resultant gels. We give the SEM(scanelectronics microscope) of ncSi/SiO2 and energy spectra of ncSi/SiO2.The effects of colloid viscosity, acid catalyzer concentrations, speed and time of spincoating on quality of film are revealed.In ncSi/SiO2 film, the particles (ncSi) in nanocrystalline material have the size of about 1nm to 100nm, and there are several new effects upon conventional material among them e.g. microsized effect, quantumsize effect and macroquantum tunneling effect. It is just because of the existence of these effects nanocrystalline material shows out different characteristics on mechanics, thermodynamics, electricity and chemistry. So from the moment of its appearance, nanocrystalline material had been attracting more and more attentions of scientists on it.