共查询到20条相似文献,搜索用时 78 毫秒
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研究了非掺GaAs半绝缘单晶的液封垂直梯度凝固法(VGF)生长技术,解决了Si沾污和C浓度的控制问题,得到了直径2英寸非掺半绝缘低位错单晶。测试表明:该单晶的位错密度较LEC单晶下降近一个数量级,电学参数与LEC单晶类似,接近国个VGF单晶的的参数指标。 相似文献
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介绍了国产ZFLO18型高压单晶炉的主要性能和特点,主要是:热态下(坩埚加热到1500℃)可经受100大气压;可采用电阻、高频两种加热方式;配用工业电视可遥控整个拉品过程;上下炉膛采用螺帽连接既使受力均匀,开启也较方便;上下轴均有压力补偿,采用“O”形密封,运转比较灵活;可用热偶取出信号进行控温等。用液体复盖直拉法(LEC法)在该单晶炉内进行了GaP单晶生长实验,采用电阻加热方式,在我国首次拉制出了适于绿色(黄、红)发光二极管衬底的掺Te的GaP单晶。详细介绍了所用热场配置、掺杂计算,工艺 相似文献
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砷化镓单晶材料是当今世界移动通讯、微波光电集成电路及光电子领域中的基础衬底材料。国际上GaAs单晶生长方法的主流技术是:液封直拉(LEC)法和水平布里奇曼(HB)法。随着砷化镓单晶材料朝大直径、高质量、低成本方向发展,垂直梯度凝固技术VGF法生长GaAs晶片具有设备结构简单,操作方便,易实现自动控制,适合产业化生产,晶体具有温度梯度小、热应力小,位错密度低,甚至可生长无位错单晶等特点。近几年,国际上采用VGF法生长GaAs单晶已进入φ4'产业化,φ6'正处于产业 相似文献
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本文报道了Pb2MoO5单晶的坩埚下降法生长工艺.按照精确的化学计量比进行配料,应用高温固相反应合成Pb2MoO5多晶料;在晶体生长过程中,控制炉体温度于1050~1070℃,调节固液界面温度梯度为30~40℃/cm,按照0.6~1.0 mm/h的下降速率,通过改进的坩埚下降法生长出透明完整的Pb2MoO5单晶;应用X射线衍射、差热分析、透射光谱等方法进行了单晶基本性质的表征.X射线衍射分析证实该晶体为单斜晶系,DTA/TG曲线表明该晶体在958℃一致熔融,高于此温度熔体组分出现严重挥发,该晶体在可见光波长范围具有良好的光学透过性,其吸收边位于370 nm波长附近. 相似文献
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直拉单晶炉生长过程中炉膛内真空度的高稳定性对硅单晶正常生长起到很重要的作用。本文分析了引起直拉单晶炉生长过程中炉膛内真空度不稳定的因素,通过改进单晶炉真空系统和充气系统.确保硅单晶在生长过程中单晶炉炉膛内的真空度保持高度稳定,有助于提高硅单晶生长的质量。 相似文献
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CdZnTe晶体是一种性能优畀的室温核辐射探测器材料.在熔体法生长CdZnTe晶体的过程中,生长炉的内部温场分布对获得的晶体结构和性能有很大影响.根据CdZnTe晶体的生长习性,设计了三温区单晶炉,用坩埚下降法生长出CdZnTe单晶体.通过X射线衍射、红外透过率、I-V测试等分析研究,得到了红外透过率约为61%,腐蚀蚀坑密度(EPD)为104 cm-2,电阻率为109~1010 Ω·cm的Cd0.9 Zn0.1 Te单晶体.表明三温区坩埚下降法生长的单晶体结晶质量好、成分分布均匀、EPD低、红外透过性能好且电阻率高. 相似文献
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Bing TENG Weijin KONG Ke FENG Fei YOU Lifeng CAO Degao ZHONG Lun HAO Qing SUN Sander van SMAALEN Wenhui GONG 《材料科学前沿(英文版)》2015,9(2):147
A new organic crystal of 4-N, N-dimethylamino-4′-N′-methyl-stilbazolium benzene sulfonate (DASBS) was synthesized and characterized for the first time. It is a derivative of 4-N, N-dimethylamino-4′-N′-methyl-stilbazolium tosylate (DAST) with the benzene sulfonate replacing p-toluenesulfonate. Single crystal XRD demonstrated that the crystal structure of DASBS·H2O was triclinic. The thermal analysis of this new crystal was also conducted, and the melting point was obtained to be 232°C. 相似文献
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Organic semiconductor-based photonic crystals for solar cell arrays: band gap and optical properties
Filiz Karaomerlioglu Amirullah M. Mamedov Ekmel Ozbay 《Journal of Modern Optics》2014,61(21):1754-1760
Photonic crystals (PCs) hold great potential for designing new optical devices because of the possibility of the manipulation of light with PCs. There has been an increase in research on tuning the optical properties of PCs to design devices. We design organic semiconductor-based PC structures and calculate optical properties using the plane wave expansion method and finite-difference time-domain method in an air background for a hexagonal lattice. We showed the possibility of the solar cell arrays for a 2D PC cavity on an organic semiconductor base infiltrated with a nematic liquid crystal. E7 type has been used as a nematic liquid crystal and 4,4′-Bis[4-(diphenylamino) styryl]biphenyl as an organic semiconductor material. 相似文献
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The Raman scattering intensity was measured for a colloidal crystal composed of polystyrene micro spheres and a polymer gel with a tunable continuous-wave dye laser as an excitation light source. Enhancement of the Raman scattering caused by both the electric field enhancement at the excitation frequency and the increase in the local photon density of states at the scattering frequency was expected. The observed Raman scattering intensity as a function of the excitation frequency showed a reasonable agreement with the theoretical prediction. 相似文献
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晶核的絮凝和聚结导致了AgBr孪晶的产生,从而进一步形成T颗粒,本文综述了最近在这方面的研究结果,并讨论了T颗粒形成的机理;同时还就物理成熟条件对T颗粒尺寸和形状的影响进行了讨论。 相似文献