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121.
四方相BaTiO3薄膜的自组装制备与表征 总被引:1,自引:0,他引:1
以(NH4)2TiF6、 Ba(NO3)2 和H3BO3为主要原料, 采用自组装单层膜(SAMs)技术, 以三氯十八烷基硅烷(octadecyl-trichloro-silane, OTS)为模版, 在玻璃基片上制备了四方相钛酸钡晶态薄膜. 改性基板的亲水性测定与原子力显微镜(AFM)测试表明, 紫外光照射使基板由疏水转变为亲水, 能够对OTS-SAM起到修饰作用. 金相显微镜观察结果显示,OTS单分子膜指导沉积的薄膜样品表面均匀, 表明OTSSAM对钛酸钡薄膜的沉积具有诱导作用; X射线衍射(XRD)与扫描电镜(SEM)表征显示, 空气中600℃下保温2h实现了薄膜由非晶态向四方相BaTiO3晶态薄膜的转化过程, 制备的钛酸钡薄膜在基板表面呈纳米线状生长, 线长约在500~1000nm之间, 相互连接的晶粒大小约为100nm. 文章同时对自组装单层膜和钛酸钡薄膜的形成机理进行了探讨. 相似文献
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D. Mangelinck P. Gas T. Badche E. Taing F. Nemouchi C. Perrin-Pellegrino M. Vuaroqueaux S. Niel P. Fornara J. M. Mirabel L. Fares P. H. Albarede 《Microelectronic Engineering》2003,70(2-4):220-225
The formation of Ti silicides has been examined in flash memories with 0.25 μm linewidth by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. It has been observed that, after the first rapid thermal process and the selective metal etch, there is no silicide on the source and on a majority of drain contacts while C49-TiSi2 is found on the gate. A pre-amorphisation implant increases drastically the formation of C49-TiSi2 in the drain zone while modifications of annealing conditions have little impact. These results indicate that the formation of C49-TiSi2 is most likely controlled by nucleation and that this nucleation is sensitive to both the width and the length of the reaction zone. The formation of a Ti rich silicide may play an important role in this nucleation by decreasing the driving force for the formation of C49-TiSi2. Curiously enough, the formation of C49-TiSi2 appears thus as a major concern for the salicide process in flash memories. 相似文献
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Using first-principles calculations based on density functional theory, we have investigated the nature of H defects in CdTe.
The formation energy calculations indicate that the ground state position of the H inside the CdTe lattice depends on charge
state: the lowest energy position for H0 and H+ is at the bond center site, while H− prefers the tetrahedral interstitial site with Cd nearest neighbors (TCd). We find that H in CdTe acts as an amphoteric impurity. In p-type samples, H is in a positive charge state, acting as a donor to neutralize the free holes in the valence band, and in
n-type samples H acquires an electron, compensating the donors in the sample. 相似文献
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Junction Stability in Ion-Implanted Mercury Cadmium Telluride 总被引:1,自引:0,他引:1
Ion implantation into HgCdTe results in the production of Hg interstitials, which can be subsequently driven into the HgCdTe
by an annealing process. This diffusive drive-in of the Hg interstitials fills vacancies and kicks out group I impurities
and results in the formation of an n–p junction. In this work we report on the production of interstitials during baking subsequent to the ion implantation process.
Various concentrations of metal vacancies were first introduced into mid-wavelength infrared (MWIR, 3 μm to 5 μm) HgCdTe by annealing under tellurium-saturated conditions at various temperatures. Baking subsequent to planar implantation
of boron produced n–p junctions whose depths were measured by defect etching. The results were modeled using a simple diffusion limited model from
a fixed surface concentration. The surface concentration was allowed to decrease exponentially to zero after a time, found
to be of the order of ∼80 h to 150 h. Exhaustion of the interstitials sources produced by the implantation was nearly complete
after ∼400 h. The total number of mercury interstitials produced was approximately 50% of the implant dosage. 相似文献
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