A silicon dioxide fiber-reinforced silicon nitride matrix(SiOJSi3N4)composite used for radomes was prepared by chemical vapor infiltration(CVI)process using the SiCl4-NH3-H2 system.The effects of the process condition...A silicon dioxide fiber-reinforced silicon nitride matrix(SiOJSi3N4)composite used for radomes was prepared by chemical vapor infiltration(CVI)process using the SiCl4-NH3-H2 system.The effects of the process conditions,including infiltration temperature,infiltration time,and gas flux were investigated.The energy dispersion spectra(EDS)result showed that the main elements of this composite contained Si,N,and O.The X-ray diffraction(XRD)results indicated that phases of the composite before and after treatment at 1350℃were all amorphous.A little fiber pull-out was observed on the cross section of the composite by scan electron microscope(SEM).As a result,the composite exhibited good thermal stability,but an appropriate interface was necessary between the fiber and the matrix.展开更多
用 H2 和 Ga_2O_3的高温反应形成元素 Ga 的恒定表面源,通过 SiO_2-Si 复合结构实现了 Ga 在 Si 中的高均匀性掺杂;利用二次离子质谱分析(SIMS)、扩展电阻(SRP)、四探针测试等方法,对 P 型杂质 Ga 在 SiO_2薄膜、SiO_2-Si 两固相接触的...用 H2 和 Ga_2O_3的高温反应形成元素 Ga 的恒定表面源,通过 SiO_2-Si 复合结构实现了 Ga 在 Si 中的高均匀性掺杂;利用二次离子质谱分析(SIMS)、扩展电阻(SRP)、四探针测试等方法,对 P 型杂质 Ga 在 SiO_2薄膜、SiO_2-Si 两固相接触的内界面、近 Si 表面的热分布进行分析;揭示出开管方式扩散 Ga 的实质是由 SiO_2薄膜对 Ga 原子的快速输运及其在 SiO_2-Si 内界面分凝效应两者统一的必然结果;并对该过程 Ga 杂质浓度分布机理进行了分析和讨论。展开更多
基金Science Challenge Project(TZ2016003-1-105)CAEP Microsystem and THz Science and Technology Foundation(CAEPMT201501)National Basic Research Program of China(2011CB606405)。
基金This study was financially supported by the Key Foundation of National Science in China(No.90405015)the National Elitist Youth Foundation of China(No.50425208the Doctorate Foundation of Northwestern Polytechnical University(CX200505).
摘要A silicon dioxide fiber-reinforced silicon nitride matrix(SiOJSi3N4)composite used for radomes was prepared by chemical vapor infiltration(CVI)process using the SiCl4-NH3-H2 system.The effects of the process conditions,including infiltration temperature,infiltration time,and gas flux were investigated.The energy dispersion spectra(EDS)result showed that the main elements of this composite contained Si,N,and O.The X-ray diffraction(XRD)results indicated that phases of the composite before and after treatment at 1350℃were all amorphous.A little fiber pull-out was observed on the cross section of the composite by scan electron microscope(SEM).As a result,the composite exhibited good thermal stability,but an appropriate interface was necessary between the fiber and the matrix.
摘要用 H2 和 Ga_2O_3的高温反应形成元素 Ga 的恒定表面源,通过 SiO_2-Si 复合结构实现了 Ga 在 Si 中的高均匀性掺杂;利用二次离子质谱分析(SIMS)、扩展电阻(SRP)、四探针测试等方法,对 P 型杂质 Ga 在 SiO_2薄膜、SiO_2-Si 两固相接触的内界面、近 Si 表面的热分布进行分析;揭示出开管方式扩散 Ga 的实质是由 SiO_2薄膜对 Ga 原子的快速输运及其在 SiO_2-Si 内界面分凝效应两者统一的必然结果;并对该过程 Ga 杂质浓度分布机理进行了分析和讨论。