论文部分内容阅读
研究了用作硅中扩散源的含砷的二氧化硅玻璃。这种玻璃是在由四乙氧基硅烷蒸气、三氯化砷蒸气和氧气组成的混合气氛中于500～700℃的温度下淀积在加热的硅衬底上的。采用红外分光光谱学和电子衍射分析等方法研究了这种玻璃的结构及其在氧气气氛、氢气气氛、氮气气氛和真空中进行热处理后结构的变化。同时也测量了玻璃的密度、三氧化二砷克分子含量的百分比和折射率。经过氢气中热处理后,玻璃中的三氧化二砷很容易还原为砷,而随后在氧气中进行热处理时砷又再氧化为三氧化二砷。如果在氧气中进行长时间的热处理,玻璃表面会结晶化。在氧气中进行热处理后引起的破坏可以由这种玻璃的软化点低和热膨胀系数大来解释。
Arsenic-containing silica glass was investigated as a diffusion source in silicon. This glass is deposited on a heated silicon substrate at a temperature of 500 to 700 ° C in a mixed atmosphere of tetraethoxysilane vapor, arsenic trichloride vapor and oxygen gas. The structure of the glass and its structure change after heat treatment in oxygen, hydrogen, nitrogen and vacuum were investigated by means of infrared spectroscopy and electron diffraction analysis. The glass density, the percentage of arsenic trioxide and the refractive index were also measured. After the heat treatment in hydrogen, the arsenic trioxide in the glass is easily reduced to arsenic, and then the arsenic is oxidized to arsenic trioxide again by heat treatment in oxygen. If prolonged in oxygen heat treatment, the glass surface will crystallize. The damage caused after the heat treatment in oxygen can be explained by the low softening point and the large thermal expansion coefficient of this glass.