共查询到19条相似文献,搜索用时 62 毫秒
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CdTe/GaAs是HgCdTe分子束外延的重要替代衬底材料。用X双晶衍射和光致发光测试研究了分子束外延生长的CdTe(211)B/gAs(211)B的晶体结构质量,表明外延膜昌体结构完整,具有很高的质量。用高分辨率的透射电镜研究其界面特性,观察到CdTe(211)B相对于GaAs(211)B向着(111)方向倾斜一个小角度,界面的四面体键网发生扭曲,由于晶格失配,在界面存在很高的失配位错密度。 相似文献
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文中报导了用分子束外廷工艺在GaAs(211)B衬底上生长了较高质量的中、长波HgCdTe薄膜材料。生长后的材料通过退火进行转型和调节电性参数。选择的组分分别为x=0.330和0.226的两种材料,77K时载流子浓度和迁移率分别为p=6.7×1015cm-3、up=260cm2V-1s-1和4.45×1015cm-3、410cm2V-1s-1。研制了平面型中、长波线列光伏探测器,其典型的探测器D分别为5.0×1010cmHz1/2W-1和2.68×1010cmHz1/2W-1(180°视场下),其中64元线列中波探测器与CMOS电路芯片在杜瓦瓶中耦含后读出并实现了红外成像演示。 相似文献
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报道了用MBE的方法,在3英寸Si衬底上制备ZnTe/CdTe(211)B复合衬底材料的初步研究结果,该研究结果将能够直接应用于大面积Si基HgCdTe IRFPA材料的生长.经过Si(211)衬底低温表面处理、ZnTe低温成核、高温退火、高温ZnTe、CdTe层的生长研究,用MBE方法成功地获得了3英寸Si基ZnTe/CdTe(211)B复合衬底材料.CdTe厚度大于10μm,XRD FWHM平均值为120arc sec,最好达到100arc sec,无(133)孪晶和其他多晶晶向. 相似文献
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我们用分子束外延法在GaAs(100)衬底上生长一种新型的Ⅱ-Ⅳ族宽禁带化合物薄膜Zn1-xMgxSySe1-y.改变生长条件,可以控制Mg和S的组分在0≤x≤1,0≤y≤1.Mg和S的组分用俄歇电子能谱测定.用X-射线衍射技术对样品结构进行的研究发现,对任意Mg和S的组分,ZnMgSSe均为闪锌矿结构.用椭圆偏振光谱仪对材料的能隙和折射率进行的研究表明,加入Mg以后ZnMgSSe样品的折射率比ZnSSe样品的折射率要小,并且ZnMgSSe样品的折射率随民的增大而变小.合理选择x、y,在2.8eV<Eg< 相似文献
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国内首次报道用热壁外延(HWE)技术在(100)GaAs衬底上生长出Cd_(0.96)Zn_(0.04)Te(111)薄膜。结果表明,薄膜在15~20μm厚时X射线双晶衍射回摆曲线半高宽在100弧秒以下,其位错腐蚀坑密度等于甚至小于10 ̄3cm ̄(-2)薄膜组分、层厚均匀,表面光亮如镜,质量达到国际先进水平,优于国内Cd_(0.96)Zn_(0.04)Te块晶,是外延生长HgCdTe的理想替代式衬底。文章强调了生长前GaAs衬底,多晶源预处理的重要性。 相似文献
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As在HgCdTe分子束外延中的表面粘附系数 总被引:4,自引:1,他引:4
报道了用二次离子质谱分析 (SIMS)方法对As在碲镉汞分子束外延中的掺入行为的研究结果 .发现As在CdTe、HgCdTe表面的粘附系数很低 ,并与Hg的介入密切相关 .对于单晶HgCdTe外延 ,在 170℃生长温度下As的粘附率相对于多晶室温淀积仅为 3× 10 -4,在此生长温度下 ,通过优化生长条件获得了表面形貌良好的外延材料 .通过控制As束源炉的温度可以很好地控制As在HgCdTe层中的原子浓度 . 相似文献
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研究了离子损伤对等离子体辅助分子束外延生长的GaNAs/GaAs和GaInNAs/GaAs量子阱的影响.研究表明离子损伤是影响GaNAs和GaInNAs量子阱质量的关键因素.去离子磁场能有效地去除了等离子体活化产生的氮离子.对于使用去离子磁场生长的GaNAs和GaInNAs量子阱样品,X射线衍射测量和PL谱测量都表明样品的质量被显著地提高.GaInAs量子阱的PL强度已经提高到可以和同样条件下生长的GaInAs量子阱相比较.研究也表明使用的磁场强度越强,样品的光学质量提高越明显. 相似文献
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采用分子束外延技术生长了GaAs/AlGaAs单量子阱得多量子阱材料。采用GaAs/AlGaAs超晶格缓冲层掩埋衬底缺陷,获得的量子阱结构材料被成功地用于制作量子阱激光器。波长为778nm的激光器,最低阈值电流为30mA,室温下线性光功率大于20mW。 相似文献
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在10K低温下对分子束外延(MBE)生长的CdTe(111)B/GaAs(100)/CdTe(211)B/GaAs(211)B外延膜进行了光致发光(PL)测量,得到了PL谱和带边激子辐射的精细结构.计算得到束缚激子的半峰宽(FWHM)分别为0.2~0.smeV和1~2meV.实验结果表明外廷膜的质量和生长工艺均良好. 相似文献
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利用高分辨率X射线衍射技术对分子束外延CdTe(211)B/Si(211)材料的CdTe外延薄膜进行了倒易点二维扫描,并通过获得的对称衍射面和非对称衍射面的倒易空间图,对CdTe缓冲层的剪切应变状况进行了分析.研究发现,对于CdTe/Si结构,随着CdTe厚度的增加,[1-1-1]、[01-1]两个方向的剪切角γ[1-1-1]和γ[01-1]都有变小的趋势,且γ[1-1-1]的大小约为γ[01-1]的两倍;对于CdTe/ZnTe/Si结构,ZnTe缓冲层的引入可以有效地降低CdTe层的剪切应变. 相似文献
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利用远红外反射光谱和拉曼散射光谱法测量了GaAs/SrTiO3外延单晶薄膜样品,研究了这种新型异结构的晶格振动光学特性。实验结果表明:在钙钛矿型结构的SrTiO3衬底上外延生长的GaAs薄膜具有单晶结构,有与GaAs单晶体材料相同的晶格振动特性。 相似文献
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文章利用高分辨率X射线衍射技术对分子束外延CdTe(211)B/Si(211)材料的CdTe外延薄膜进行了倒易点二维扫描,并通过获得的对称衍射面和非对称衍射面的倒易空间图,对CdTe外延层的剪切应变和正应变状况进行了分析.研究发现,对于CdTe/Si结构,随着CdTe厚度的增加,[1-1-1]、[01-1]两个方向的剪切角γ[1-1-1]和λ[01-1]都有变小的趋势,且γ[1-1-1]的大小约为γ[01-1]的两倍;对于CdTe/ZnTe/Si,ZnTe缓冲层的引入可以有效地降低CdTe层的剪切应变.CdTe层的正应变表现为张应变,主要来源于CdTe和Si的热膨胀系数存在差异,而在从生长温度280℃降至室温20℃的过程产生的热应变. 相似文献
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Giacomo Badano Xavier Baudry Philippe Ballet Philippe Duvaut Alain Million Eric Micoud Sabeur Kaismoune Paul Fougères Sophie Mibord Pierre Tran-Van Arnaud Etcheberry 《Journal of Electronic Materials》2008,37(9):1369-1375
We characterize the surface of molecular-beam epitaxy (MBE)-grown CdTe(211)B/Ge(211) by atomic-force microscopy (AFM), optical interference microscopy, and generalized ellipsometry (GE). We find that, for substrate temperatures above 300°C, the surface is rough and hazy; the AFM root-mean-square roughness is of the order of 150 Å. It appears from GE that the optical response is anisotropic, the principal axes of anisotropy being along the $ [\overline{1} 11] We characterize the surface of molecular-beam epitaxy (MBE)-grown CdTe(211)B/Ge(211) by atomic-force microscopy (AFM), optical
interference microscopy, and generalized ellipsometry (GE). We find that, for substrate temperatures above 300°C, the surface
is rough and hazy; the AFM root-mean-square roughness is of the order of 150 ?. It appears from GE that the optical response
is anisotropic, the principal axes of anisotropy being along the and directions. For a substrate temperature of approximately 300°C, the surface is smooth and mirror-like and the AFM roughness
is as low as 45 ?. The sample is still anisotropic, even though the magnitude of the cross-polarized reflection coefficients
are very small in this case. It appears that the anisotropy originates from the surface roughness, not the bulk. 相似文献
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Microstructural and optical characterization of CdTe(211)B/ZnTe/Si(211) grown by molecular beam epitaxy 总被引:2,自引:0,他引:2
S. Rujirawat David J. Smith J. P. Faurie G. Neu V. Nathan S. Sivananthan 《Journal of Electronic Materials》1998,27(9):1047-1052
CdTe layers have been grown by molecular beam epitaxy on 3 inch nominal Si(211) under various conditions to study the effect
of growth parameters on the structural quality. The microstructure of several samples was investigated by high resolution
transmission electron microscopy (HRTEM). The orientation of the CdTe layers was affected strongly by the ZnTe buffer deposition
temperature. Both single domain CdTe(133)B and CdTe(211)B were obtained by selective growth of ZnTe buffer layers at different
temperatures. We demonstrated that thin ZnTe buffer layers (<2 nm) are sufficient to maintain the (211) orientation. CdTe
deposited at ∼300°C grows with its normal lattice parameter from the onset of growth, demonstrating the effective strain accommodation
of the buffer layer. The low tilt angle (<1°) between CdTe[211] and Si[211] indicates that high miscut Si(211) substrates
are unnecessary. From low temperature photoluminescence, it is shown that Cd-substituted Li is the main residual impurity
in the CdTe layer. In addition, deep emission bands are attributed to the presence of AsTe and AgCd acceptors. There is no evidence that copper plays a role in the impurity contamination of the samples. 相似文献
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The growth by molecular beam epitaxy of high quality GaAs epilayers on nonmisoriented GaAs(111)B substrates is reported. Growth control of the GaAs epilayers is achieved via in situ, real time measurement of the specular beam intensity of reflection high-energy electron diffraction (RHEED). Static surface phase maps of GaAs(111)B have been generated for a variety of incident As flux and substrate temperature conditions. The dependence of GaAs(111)B to be the optimum starting surface for the latter growth of mirror-smooth epilayers. Regimes of growth conditions are optimized in terms of the static surface phase diagram and the temporal RHEED intensity oscillations. 相似文献