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61.
Miguel A. Contreras H. Wiesner J. Tuttle K. Ramanathan R. Noufi 《Solar Energy Materials & Solar Cells》1997,49(1-4)
Considering the chalcopyrite/defect-chalcopyrite junction model for Cu(In1−xGax)Se2-based devices and our previously reported findings for the Cu(In1−xGax)3Se5 defect chalcopyrites, we have postulated that uniform high-Ga-content photovoltaic structures (with x > 0.35) do not yield acceptable device performance due to the electrical and structural differences between both types of materials (chalcopyrite and defect-chalcopyrite).In this contribution, the structural properties of the surface region of Ga containing absorber materials have been studied by grazing incidence X-ray diffraction. We find that there are significant differences between surface and bulk. A structural model is proposed for the growth of the chalcopyrite/defect-chalcopyrite junction relative to its Ga content. And we demonstrate that closely lattice matched high-Ga-content structures (x > 0.35) can produce solar cells withv acceptable performances. The high-voltage and low-current electrical outputs from high Ga structures are very desirable in module fabrication because overall resistive losses can be substantially reduced. 相似文献
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系统综述了国内外采用金属预置层后硒化法制备Cu(In,Ga)Se2(CIGS)薄膜的研究进展,重点从预置层制备过程中靶材的选择、叠层方式以及后硒化过程中硒源种类和硒化方式的选择等几个方面对各种工艺的优点、存在的问题和可能的解决方案进行讨论,并对金属预置层后硒化法的发展前景和趋势进行了展望。 相似文献
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ZHANG FaFa YANG XueLin ZHANG YuHao JIANG XianZhe LIN ZhiYuan CHEN ZhiTao LI Ding TAO YueBin WANG CunDa & ZHANG GuoYi State Key Laboratory of Artificial Microstructure Mesoscopic Physics School of Physics Peking University Beijing China 《中国科学:信息科学(英文版)》2011,(7)
A detailed study is presented on magnetic, electrical and optical properties of Ga 1-x Mn x N: Si film grown by metal organic chemical vapor deposition (MOCVD) with high-purity SiH 4 as the Si dopant source. The room-temperature field dependence magnetization and zero-field-cooled (ZFC)/field-cooled (FC) measurements indicate that the film remains room-temperature ferromagnetism and it declines slightly after Si co-doping. However, room-temperature Hall measurements indicate that the electrical property of ... 相似文献
66.
Density functional theory calculations have been carried out to determine the thermodynamic stability of various Ga species
in gallium-exchanged ZSM-5, the thermodynamics of H2 adsorption, and the most favorable pathway for H2/D2 exchange. The portion of the zeolite associated with Ga was represented by a cluster containing 7, 21, or 33 atoms. The B3LYP
hybrid method was used to account for the effects of electron exchange and correlation. The most likely form of Ga expected
in freshly exchanged and calcined ZSM-5 is ZGa(OH)2. H2 reduction of this species is projected to produce ZGa(H)(OH) and ZGa(H)2. While the thermodynamics of H2 desorption from ZGa(H)2 are favorable, the process is projected to be slow because of a high activation barrier. The most favorable pathway for H2/D2 exchange over ZGa(H)2 proceeds via Z(D)(Ga(H)2(D)) as an intermediate. Similar calculations have been carried out for H2/D2 exchange over H-ZSM-5.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
68.
A comparative study of the cell performance of CIGS thin-film solar cells fabricated using ZnO:Al and ZnO:B window layers has been carried out. ZnO:B films were deposited by RF magnetron sputtering using an undoped ZnO target in a B2H6–Ar gas mixture. The short-circuit current (Jsc) was found to improve upon the replacement of the ZnO:Al layer with ZnO:B layers. This improvement in Jsc is attributed to an increase in quantum efficiency due to the higher optical transmission of the ZnO:B layer in the near-infrared region. The best cell fabricated with a MgF2/ZnO:B/i-ZnO/CdS/CIGS/Mo structure yielded an active area efficiency of 18.0% with Voc=0.645 V, Jsc=36.8 mA/cm2, FF=0.76, and an active area of 0.2 cm2 under AM 1.5 illumination. 相似文献
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70.
Si基氨化ZnO/Ga2O3薄膜制备GaN纳米线 总被引:1,自引:0,他引:1
利用射频磁控溅射法在Si(111)衬底上溅射ZnO中间层和Ga2O3薄膜,然后在管式炉中常压下通氨气对ZnO/Ga2O3薄膜进行氨化,高温下ZnO层在氨气气氛中挥发,而Ga2O3薄膜和氨气反应合成出GaN纳米线.X射线衍射测量结果表明利用该方法制备的GaN纳米线具有沿c轴方向择优生长的六角纤锌矿结构.利用扫描电子显微镜、透射电子显微镜、傅里叶红外透射谱、能量弥散谱及选区电子衍射观测并分析了样品的形貌、成分和晶格结构.研究发现ZnO层的挥发有利于Ga2O3和NH3反应合成GaN纳米线. 相似文献