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101.
Sputter deposited molybdenum (Mo) thin films are used as back contact layer for Cu(In1−xGax)(Se1−ySy)2 based thin film solar cells. Desirable properties of Mo films include chemical and mechanical inertness during the deposition process, high conductivity, appropriate thermal expansion coefficient with contact layers and a low contact resistance with the absorber layer. Mo films were deposited over soda-lime glass substrates using DC-plasma magnetron sputtering technique. A 23 full factorial design was made to investigate the effect of applied power, chamber pressure, and substrate temperature on structural, morphological, and electrical properties of the films. All the films were of submicron thickness with growth rates in the range of 34–82 nm/min and either voided columnar or dense growth morphology. Atomic force microscope studies revealed very smooth surface topography with average surface roughness values of upto 17 nm. X-ray diffraction studies indicated, all the films to be monocrystalline with (001) orientation and crystallite size in the range of 4.6–21 nm. The films exhibited varying degrees of compressive or tensile residual stresses when produced at low or high chamber pressure. Low pressure synthesis resulted in film buckling and cracking due to poor interfacial strength as characterized by failure during the tape test. Measurement of electrical resistivity for all the films yielded a minimum value of 42 μΩ cm for Mo films deposited at 200 W DC power. 相似文献
102.
对4H-SiC雪崩光电探测器的Ti/Al/Au p型欧姆接触进行了详细的研究。通过线性传输线模型(LTLM)测得经930℃退火后欧姆接触的最小比接触电阻为5.4×10~(-4)Ωcm~2。分别用扫描电子显微镜(SEM)、俄歇电子能谱(AES)、X射线光电子能谱(XPS)和X射线衍射谱(XRD)对退火前后的表面形貌、金属之间以及金-半接触界面之间相互反应及扩散情况进行测试与分析,发现了影响欧姆接触性能的主要原冈。对采用此欧姆接触制备的4H-SiC雪崩光电探测器进行测试,发现器件的击穿电压约为-55 V,此时其p型电极处的电压降仅为0.82 mV,可以满足4H-SiC雪崩光电探测器在高压下工作的需要。 相似文献
103.
应用热力学原理定量分析了植物水分异质成核的结冰机理:植物体微小空腔内的水分在结冰时,腔壁起着凝结核的作用,即存在异质成核结冰过程.水分异质成核的温度(即冰点) T与球形腔半径 R及冰水对墙壁的浸润性能的差异(用接触角θ表示)之间符合函数关系 T= T( R,cosθ).对于每一个cosθ值,当 R取某一确定值 R时,冰点达到最低值 Tm in, Tm in可达- 36 ℃. 相似文献
104.
105.
A method is presented to control the vibration of high-speed cannonball transport mechanism due to the reduction of its weight, which adhere a nonlinear Zn-27Al-1Cu damping alloy layer and a constraint layer partly to the part of mechanism driven by impact. Based on the equivalent viscous damping theory and using curve fitting to describe the rule of the dissipation factor of damping alloy changing with stress, the nonlinear constitutive relation of Zn-27Al-1Cu damping alloy is given. The nonlinear spring damping contact model is adopted to describe the contact force of the clearance joint.Based on the nonlinear finite element contact theory, the outer impact contact force between the mechanism and its working environment is analyzed, and a coupled dynamic model of structural impact and mechanism motion with clearance joint is put forward. A dynamic model is established for the cannonball transport mechanism partly adhering Zn-27Al-lCu damping alloy layer and constraint layer under complex impact conditions. At last, the feasibility of the method presented is proved by numerical simulation. 相似文献
106.
F. Ren T. R. Fullowan S. N. G. Chu S. J. Pearton W. S. Hobson A. B. Emerson 《Journal of Electronic Materials》1991,20(4):305-308
We report the use of a Mo barrier layer within Ni/Au-Ge based ohmic contacts to GaAs for eliminating an etch stop reaction
that occurs during Cl-based dry etching of heterojunction bipolar transistors. With conventional Ni/Au-Ge/Ag ohmic contacts,
chlorinecontaining discharges produce a passivating layer of AgCl on the semiconductor surface, preventing further etching.
This layer is absent when the Ag in the contact is replaced with Mo. The Mo has several advantages over other diffusion barrier
layers and yields contacts with excellent adhesion, smooth morphology, and sharp edge definition. The average contact resistivity
of these contacts ton
+-GaAs(n = 6 × 1018 cm-3) was 0.074 ohm-mm, which is lower than the typical contact resistivity of conventional Ni/Au-Ge/ Ag metallization (0.11 ohm-mm). 相似文献
107.
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110.
本文将围绕计算机网络技术与电子信息工程的概念与联系,针对计算机网络技术在电子信息工程中的具体应用展开全面论述. 相似文献