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低温APCVD法制备氮化硅薄膜 总被引:7,自引:0,他引:7
本实验用常压化学气相沉积法(APCVD)在平玻璃基板上沉积了氮化硅薄膜,研究了基板温度、反应气体比例,热处理等对氮化硅薄膜制备的影响,发现在700℃以下,NH3/SiH4流量比例为15/1时制得较纯的氮化硅薄膜,比常规APCVD法制备温度低大约150℃。 相似文献
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以氯化锶、硝酸铋和钛酸丁酯为原料,柠檬酸为络合剂,配制了稳定的SrBi4Ti4O15(SBTi)前驱液.采用层层快速退火工艺,在Pt/Ti/SiO2/Si基片上制备了a轴取向增强的SBTi铁电薄膜,通过场发射扫描电镜、环境扫描电镜及X射线衍射等微观分析手段研究了保温时间和成膜次数对薄膜结晶性、微观结构和生长行为的影响.结果表明:层层快速退火工艺,可有效抑制焦绿石相的形成.随着退火时间的延长,薄膜的结晶性变好;但退火时间延长到30 min以上,薄膜的结晶性变差.由于SBTi晶体生长的各向异性及单层膜厚对晶体沿[119]方向生长的限制,随着涂覆次数的增加,SBTi薄膜(119)峰和(200)峰的强度逐渐增大,而(00l)峰的强度反而略有减少,从而使I(200)/I(119)、I(200)/I(0010)、I(119)/I(0010)逐渐增大. 相似文献
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Maria C. Gust Leslie A. Momoda Neal D. Evans Martha L. Mecartney 《Journal of the American Ceramic Society》2001,84(5):1087-1092
Microstructural development of thin-film barium strontium titanate (Ba x Sr1– x TiO3 ) as a function of strontium concentration and thermal treatment were studied, using transmission electron microscopy (TEM) and X-ray diffractometry (XRD). Thin films, ∼250 nm thick, were spin-coated onto Pt/Ti/SiO2 /Si substrates, using methoxypropoxide alkoxide precursors, and crystallized by heat-treating at 700°C. All films had the cubic perovskite structure, and their lattice parameters varied linearly with strontium content. Films with higher strontium concentrations had a larger average grain size. In situ TEM heating experiments, combined with differential thermal analysis/thermogravimetric analysis results, suggest that the gel films crystallize as an intermediate carbonate phase, Ba x Sr1– x TiO2 CO3 (with a solid solution range from x = 1 to x = 0). Before decomposition at 600°C, this carbonate phase inhibits the formation of the desired perovskite phase. 相似文献
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Crystalline PbTiO3 thin films were successfully deposited on (111)-oriented Pt/Ti/SiO2 /Si and on (200)-oriented Pt/SiO2 /Si by metalorganic chemical vapor deposition at a substrate temperature of 400°C, using a β-diketonate complex of Pb(tmhd)2 (tmhd = 2,2,6,6-tetramethyl-3,5-heptanedionate) and titanium isopropoxide as source precursors. The dependence of the formation of crystalline PbTiO3 phase on the Pb/Ti input precursor ratio is qualitatively described. The structure of the films deposited at 400°C changed from amorphous to polycrystalline with an increase of the Pb/Ti ratio from 1.1 to 5.0, including a partially crystallized structure at some intermediate ratio. Partial crystallization of as-grown PbTiO3 film was analyzed by scanning electron microscopy, micro-Raman, and Auger electron spectroscopy measurements. It was found that the control of excess Pb precursor through a change in the Pb/Ti ratio is the key process parameter for the formation of crystalline PbTiO3 phase in the low-temperature MOCVD process. 相似文献
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近年来研究表明,在微波等离子体化学气相沉积法(MPCVD)制备金刚石的过程中,增大反应气压和微波功率是提高金刚石生长速率的有效途径.本文采用自主改进的圆柱谐振腔式MPCVD装置,以H2-CH4为气源,在反应气压30 kPa、微波功率5.8 kW、CH4浓度不同的条件下进行了多晶金刚石膜的制备研究,并采用扫描电镜、X-射线衍射和激光拉曼光谱技术对所制备样品的表面形貌、物相及品质进行了分析.结果表明,CH4浓度由2.5%提高至5%,金刚石膜的质量较好,沉积速率由7.5μm/h提高至27.5μm/h. 相似文献
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Emmanouil Lioudakis Andreas Othonos Ch. B. Lioutas N. Vouroutzis 《Nanoscale research letters》2008,3(1):1-5
We have studied ultrafast carrier dynamics in nanocrystalline silicon films with thickness of a few nanometers where boundary-related
states and quantum confinement play an important role. Transient non-degenerated photoinduced absorption measurements have
been employed to investigate the effects of grain boundaries and quantum confinement on the relaxation dynamics of photogenerated
carriers. An observed long initial rise of the photoinduced absorption for the thicker films agrees well with the existence
of boundary-related states acting as fast traps. With decreasing the thickness of material, the relaxation dynamics become
faster since the density of boundary-related states increases. Furthermore, probing with longer wavelengths we are able to
time-resolve optical paths with faster relaxations. This fact is strongly correlated with probing in different points of the
first Brillouin zone of the band structure of these materials. 相似文献
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采用等离子体增强化学气相沉积法(PECVD)以SiH4和N2为反应气体,分别在射频功率、硅烷稀释度[SiH4/N2]、衬底温度为变量的情况下制备了富硅氮化硅薄膜材料,利用X射线衍射谱(XRD)、傅里叶变换红外谱(FTIR)、紫外-可见光吸收谱(UV-Vis)对薄膜材料进行了表征,并研究了薄膜材料的微结构和晶化状况、光学特性等.实验结果表明,所沉积薄膜都为富硅的非晶氮化硅材料,改变射频功率、硅烷稀释度和衬底温度可以控制氮化硅薄膜中N元素的含量、光学带隙的大小和薄膜的折射率,并制备出最适宜富硅氮化硅薄膜,为进一步退火析出硅量子点奠定了基础. 相似文献
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介绍某多晶硅厂对硅粉加料采用密相气力输送技术的输送方式和工艺流程,分析了该气力输送系统中主要设备和管道、阀门选型及设计时的考虑因素。 相似文献