排序方式: 共有108条查询结果,搜索用时 15 毫秒
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利用固源分子束外延(SSMBE)生长技术, 在1350K的衬底温度下, 通过改变Si束流强度, 在6H-SiC(0001)面上外延生长6H-SiC/3C-SiC/6H-SiC量子阱结构薄膜, 并用反射高能电子衍射(RHEED)与光致发光(PL)谱对生长的薄膜的晶型和发光特性进行表征. RHEED 结果显示生长的薄膜为6H-SiC/3C-SiC/6H-SiC量子阱结构薄膜. 室温下He-Gd激光激发的光致发光(PL)谱显示, 薄膜在480-600 nm范围内存在衬底未观察到的较强发光. 拟合得到的发光峰与依据量子阱结构模型计算出的发光位置较为一致. 由此表明, 该强发光带可能是6H-SiC/3C-SiC/6H-SiC量子阱结构的发光. 相似文献
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A NEW METHOD TO ENHANCE THE MAGNETISM OF Fe OVERLAYER ON GaAs(100): SULFUR PASSIVATION USING CH3CSNH2 下载免费PDF全文
Ferromagnetic resonance (FMR) has been used to investigat the magnetism of Fe overlayer on S-passivated GaAs(lO0) pretreated by CH3CSNH2. Comparing with the magnetism of Fe overlayer on clean GaAs(100), we find that sulfur passivation can prevent Aa diffusion into Fe overlayer and weaken the interaction of As and Fe. It results in enhancing the magnetism of Fe overlayer on GaAs(100). We also investigate the effects of the pre-annealing of S- pasaivated GaAs(100) substrate on the magnetism of Fe overlayers. The results show that the maximum effective magnetization can be obtained at annealing temperature of 400℃. According to the experimental results of synchrotron radiation photoemission, it can be explained by the change of chemical composition and surface structure of the passivation layer on GaAs(100) surface after the annealing. 相似文献
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K对InP(100)表面催化氧化反应的同步辐射光电子能谱研究 总被引:1,自引:1,他引:0
利用同步辐射光电子能谱研究了K对P型InP(100)表面的催化氧化反应过程.对于O2/K/InP(100)体系的P2p、In4d和价带光电子能谱研究可知,在氧吸附的过程中,O和P、In之间发生了化学反应,O更易于与K在吸附过程中与InP(100)衬底之间的界面反应形成的K-P化合物中的P健合.碱金属K的存在并不直接和O发生作用,而是起到一种催化剂的作用,增加了电荷向氧传输的能力.使得O2的分解和吸附变得更加容易.在In4d芯能谱中,In-O之间的反应并不是很明显,而在价带谱中则可以明显地看到In-O之间反 相似文献
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The Na absorption on Si(100) 2×1 surface is studied with quantum chemistry molecular cluster method. The calculated results show that the most favourable absorption site of Na is the cave site and the charge transfer of Na atom to Si is large when the Na coverage is smaller than 0.5 monolayer (ML). A Na chain is formed along the cave sites at the 0.5 ML Na coverage, the charge transfer then becomes small. The calculated density of states show that the Na atoms are metallic along the chain. At 1 ML coverage, the Na atoms occupy both the cave and pedestal sites and form a double-layer. There is a charge transfer of 0.5e from each Na atom to the Si surface. The calculated surface energy shows that the saturation absorption of Na on Si surface is 1 ML. 相似文献
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利用同步辐射光电子能谱研究了低覆盖度Au在GaN(0001)表面的初始生长模式,肖特基势垒高 度以及界面的电子结构.结果表明,Au沉积初始阶段有界面的化学反应,随后呈三维岛状生长 .由光电子能谱实验确定的肖特基势垒高度为14 eV. 通过对界面价带谱和Au 4f芯能级谱 的分析,确定了界面化学反应的存在.利用线性缀加平面波方法计算了GaN(0001)和Au的价带 态密度并分析了化学反应产生的机理,认为在初始阶段界面形成了Au_Ga合金.
关键词:
同步辐射
光电子能谱
Au/GaN欧姆接触
态密度 相似文献
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利用同步辐射光电子能谱研究了室温下Na吸附下于P型InP(100)表面对其氮化反应的影响.通过P2p、In4d芯能级谱的变化,对Na/InP(100)表面的氮化反应的研究表明,碱金属Na的吸附对InP(100)无明显的催化氮化作用,即使采用N2/Na/N2/Na/N2/Na/InP(100)的类多层结构,在室温下也只有极少量的氨化物形成,而无明显的催化氮化反应发生.碱金属吸附层对Ⅲ-Ⅴ族半导体氮化反应的催化机制不同于碱金属对于元素半导体的催化反应机制,碱金属对元素半导体的催化氮化反应,吸附的碱金属与元素半 相似文献
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利用同步辐射光发射研究了Sm/GaAs(10)界面形成.高分辨的芯能级谱结果表明,在低覆盖度下(<0.1nm),Sm与衬底的作用较弱,形成较突出的金属/半导体界面.当Sm的覆盖度增加时,As和Ga的表面发射峰很快消失,表明Sm与Ga发生置换反应而与As形成化学键.同时,Ga原子会向Sm膜体内扩散且偏析到Sm膜表面,而As-Sm化合物只停留在界面区域.当Sm膜厚度达到0.5nm时,Sm膜开始金属化.结合理论模型,文中还详细地讨论了界面形成和界面结构. 相似文献
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A NEW METHOD TO ENHANCE THE MAGNETISM OF Fe OVERLAYER ON GaAs(100): SULFUR PASSIVATION USING CH3CSNH2 下载免费PDF全文
Ferromagnetic resonance (FMR) has been used to investigat the magnetism of Fe overlayer on S-passivated GaAs(lO0) pretreated by CH3CSNH2. Comparing with the magnetism of Fe overlayer on clean GaAs(100), we find that sulfur passivation can prevent Aa diffusion into Fe overlayer and weaken the interaction of As and Fe. It results in enhancing the magnetism of Fe overlayer on GaAs(100). We also investigate the effects of the pre-annealing of S- pasaivated GaAs(100) substrate on the magnetism of Fe overlayers. The results show that the maximum effective magnetization can be obtained at annealing temperature of 400℃. According to the experimental results of synchrotron radiation photoemission, it can be explained by the change of chemical composition and surface structure of the passivation layer on GaAs(100) surface after the annealing. 相似文献