衬底及生长工艺对Hg1—xCdxTe液相外延薄膜的影响

用扫描电子显微镜（ＳＥＭ）、能量散射Ｘ射线分析（ＥＤＸ）及Ｘ射线双晶摇摆曲线（ＤＣＲＣ）方法对衬底及Ｈｇ１－ｘＣｄｘＴｅ液相外延（ＬＰＥ）薄膜的生长表面进行了研究。发现采用生长前衬底表面覆盖、回熔ＬＰＥ生长措施，可以防止衬底沾污对液相外延层形貌的影响，大大改善Ｈｇ１－ｘＣｄｘＴｅ外延层的晶体质量。     

衬底及生长工艺对Hg_1－_xCd_xTe液相外延薄膜的影响

用扫描电子显微镜（ＳＥＭ）、能量散射Ｘ射线分析（ＥＤＸ）及Ｘ射线双晶摇摆曲线（ＤＣＲＣ）方法对衬底及Ｈｇ１－ｘＣｄｘＴｅ液相外延（ＬＰＥ）薄膜的生长表面进行了研究。发现采用生长前衬底表面覆盖、回熔ＬＰＥ生长措施，可以防止衬底沾污对液相外延层形貌的影响，大大改善Ｈｇ１－ｘＣｄｘＴｅ外延层的晶体质量     

XPS定量测量三元合金ZnS1—xTex薄膜组分x的研究

利用ＸＰＳ定量测量分子束外延生长的三元合金碲硫锌ＺｎＳ１－ｘＴｅｘ（０〈ｘ〈１）薄膜的组分ｘ,对比用高分辨率Ｘ射线双晶衍射技术的测量结果,相对误差小于１０％。     

HgCdTe表面钝化——阳极氟化的初步研究

本文尝试采用非含水的ＮＨ４Ｆ或ＫＦ以及含水的ＫＦ电解质溶液对Ｈｇ１－ｘＣｄｘＴｅ（ｘ＝０．２）表面的阳极氟化进行了研究，着重分析了阳极氟化膜生长的基本过程及其机理，讨论了阳极氟化条件及工艺对薄膜组成及质量的影响。     

HgCdTe晶体ACRT-B法生长过程的分凝特性研究

在定量估算的基础上，明确了Ｈｇ１－ｘＣｄｘＴｅ晶体ＡＣ－ＲＴ－Ｂ法生长过程轴向溶质再分配的 经条件，导出了计算公式。以ＨｇＴｅ－ＣｄＴｅ伪二元相图为基础进行了计算表明，按照远红外控制器要求的成分配料（ｘ０＝０．２２），仅在晶锭的某一部分可获得符合成分容差的晶体，而采用其它相近的成分配比也能获得符合成分要求的晶体，采用ｘ０值更小的槽糕成分获得的满足成分要求的晶段更长，并且位于结晶质量较高的晶锭前段‘     

Hg1—xCdxTel生长中的溶质再分配及其对生长条件的限制

本文以ＨｇＴｅ－ＣｄＴｅ伪二元相图为基础，分析了Ｈｇ１－ｘＣｄｘＴｅ单晶生长过程中分凝特性及扩散规律。从维持平面生长界面的角度出发，确定了不同温度梯度下生长速度选择的上限，并从获得成分均匀晶体的角度出发讨论了晶体生长速度下限的选择条件。     

超高真空CVD生长锗硅外延层的应变驰豫

用超高真空ＣＶＤ技术在７８０℃生长了锗硅外延层及组分渐变缓冲层，并利用双晶Ｘ射线衍射仪研究了缓冲对外延层晶体质量的影响。结果表明，衬底与外延之间生长了组分几乎线性渐变的缓冲层，提高了外延层的晶体质量。     

超高真空CVD生长锗硅外延层的应变弛豫

用超高真空ＣＶＤ技术在７８０℃生长了锗硅外延层及组分渐变缓冲层,并利用双晶Ｘ射线衍射仪研究了缓冲层对外延层晶体质量的影响。结果表明,衬底与外延之间生长了组分几乎线性渐变的缓冲层,提高了外延层的晶体质量     

YBCO／STO超导外延膜的X—射线双晶衍射研究

应用Ｘ－射线双晶衍射对磁控溅射法制备的ＹＢａ２Ｃｕ３Ｏ７－ｘ／ＳｒＴｉＯ３超导外延膜和衬底之间的位向关系以及晶体完整性的研究，表明衬底和外延在相应的衍射面之间存在与两者点阵常数差元关的位向差。这种位向差与测量方法（φ角）有关，在孪晶界方向出现极值。外延摇摆曲线的半峰宽值显示外延完整性罗差，其值与测量方向有关，而不同方向的点阵常数变化却不大。这可能分别与孪晶存在孪晶有择优取向以及外延镶嵌块间夹角变化     

BRIDGMAN—Hg1—xCdxTe晶体生长时场量数值分析的进展

综述近十余年来关于Ｂｒｉｄｇｍａｎ－Ｈｇ１－ｘＣｄｘＴｅ晶体生长过程中场量的数值分析工作。评价一般Ｂｒｉｄｇｍａｎ系统的数值分析，总结和归纳计算模型及边界条件处理方法，指出存在的问题及今后应开展的研究工作。     

Growth and strain investigation of Cd0.96Zn0.04Te/GaAs by hot-wall epitaxy

A higher quality and a nearly stoichometric composition of Cd_1−yZn_yTe (y=0.04) epilayers have been successfully grown on a GaAs substrate by hot-wall epitaxy (HWE). The growth conditions regarding preheating treatment and Cd reservoir temperature were optimized. The relationship between quality and thickness was examined by four-crystal X-ray rocking curves and the best value of 120 arcsec for full width at half maximum (FWHM) was obtained. The dislocations on the interface, generated from the difference in lattice constants, were directly observed by high-resolution electron microscopy (HREM). The variation of strain with epilayer thickness shows that the density of extended defects in the epilayer decreases rapidly increasing the thickness up to 5 μm. When the epilayer thickness reaches 20 μm, the strain almost becomes zero. This result suggests that the high-quality epilayer, same as the bulk crystal, can be obtained by increasing the thickness. Photoluminescence (PL) spectra at 4.2 K show that bound-exciton (BE) emission is dominative. The strain relaxation by misfit dislocations were also explored by HREM.     

Chloride vapor-phase epitaxy of gallium nitride on silicon: Structural and luminescent characteristics of epilayers

The structure and luminescent properties of gallium nitride (GaN) epilayers grown by hydride-chloride vapor-phase epitaxy (HVPE) in a hydrogen or argon atmosphere on 2-inch Si(111) substrates with AlN buffer layers have been studied. The replacement of hydrogen atmosphere by argon for the HVPE growth of GaN leads to a decrease in the epilayer surface roughness. The ratio of intensities of the donor-acceptor and exciton bands in the luminescence spectrum decreases with decreasing growth temperature. For the best samples of GaN epilayers, the halfwidth (FWHM) of the X-ray rocking curve for the (0002) reflection was 420 sec of arc, and the FWHM of the band of exciton emission at 77 K was 48 meV.     

LPE growth of Cd doped PbTe

Cd doped PbTe epilayers were grown on Pb_0.8Sn_0.2Te substrates by liquid phase epitaxy (LPE). The Cd behavior in the solution and the solid (substrate and epilayer) was studied. The dependence of the carrier concentration on Cd doping was investigated.     

Effects of a ZnTe buffer layer on structural quality and morphology of CdTe epilayer grown on (001)GaAs by molecular beam epitaxy

The structural properties, crystalline quality and surface morphology of CdTe thin films without and with a ZnTe buffer layer grown on (001)GaAs by molecular beam epitaxy (MBE) have been studied. CdTe thin film directly prepared on GaAs substrate displays (111) orientation with an island growth mode, whereas the CdTe epilayers with a ZnTe buffer are (001)-oriented single-crystalline film with a two-dimensional (2D) growth mode. The morphology and surface root-mean-square (RMS) roughness of CdTe epilayers are also dramatically improved by using a ZnTe buffer. Furthermore, it is suggested that the high-temperature (HT) ZnTe buffer grown at 360 °C is more efficient for enhancing CdTe structural quality than the low-temperature (LT) one at 320 °C. The CdTe epilayer on the HT-ZnTe buffer shows a narrower full-width at half-maximum (FWHM) of double-crystal X-ray rocking curve (DCXRC) for (004) reflection and a smaller RMS roughness.     

GaAS/Si(100)异质外延4°偏角衬底对外延层结晶质量的提高(英文)

用低压金属有机物化学汽相沉积法(MOCVD)在Si(100)无偏角和Si(100)4°偏角衬底上外延生长GaAs层。异质外延采用两步生长法,并分别优化了两种衬底上的非晶低温缓冲层的生长条件。用X射线双晶衍射(XRD)和透射电子显微镜(TEM)对两种衬底上的GaAs外延层进行了结构表征,其中Si(100)4°偏角衬底上1.8μm厚GaAs的(004)面XRD衍射半高全宽338 arcsec,同比在无偏角衬底上的半高全宽为494arcsec,TEM图片显示4°偏角衬底上外延层中的位错密度大大降低。     

MOCVD 生长及 TEM 表征 GaAs/Al_xGa_(1-x)As 量子异质结构材料

本文报道 MOCVD 生长 GaAs/Al_xGa_(1-x)As 量子异质结构材料(超晶格、量子阱及量子共振隧穿二极管),采用横断面透射显微术表征了样品的界面结构。实验表明:多量子阱与超晶格的周期性良好,层与层之间界面清晰,采用[100]带轴入射,观察到超晶格的 TEM 卫星衍射斑,测量到量子阱中电子的子能级跃迁吸收。研究了生长工艺和材料结构的关系,分析了影响 RT 器件的因素。     

Influences of crystallographic misorientation of GaAs substrateson misfit stresses and microhardness of InGaP epilayers

InGaP epilayers were grown on the on-axis cut, 2° off, 6° off, and 10° off GaAs substrates by organo–metallic vapor phase epitaxy, and the influences of crystallographic misorientation of the substrate on the structural properties such as lattice mismatch, elastic strain, lattice curvature, misfit stress, X-ray line-width, and microhardness of the epilayers were investigated in this study. The material characterizations were carried out by the TXRD (triple-axis X-ray diffractometer) and the nanoindenter. With an increase of the substrate misorientation angle (S.M.A.), the relative incorporation of Ga atoms on the substrate surface was found to increase. Also, with an increase of S.M.A., the X-ray line-width of the InGaP epilayer was reduced, indicating that the crystal quality of the epilayer could be improved if the misoriented substrates were used. The elastic accommodation of the strain-free lattice misfit was found to be more remarkable in the misoriented samples. It was demonstrated, for the first time that the microhardness of the InGaP epilayer decreased with an increase of S.M.A. This indicated that the variation of microhardness of the epilayer was related to the improvement of the elastic characteristics and atomic displacement induced by the misoriented substrate. The results obtained demonstrated that the elastic characteristics and the crystal quality of the InGaP epilayer were remarkably enhanced and the microhardness of the epilayer decreased when the misoriented substrates were employed.     

超高真空CVD生长锗硅外延层及其双晶X射线衍射研究

利用自行研制的超高真空化学气相沉积系统 ,在直径 3英寸的衬底硅片上生长了锗硅应变外延层 ,并进行了实时掺杂生长。利用双晶X射线衍射技术测试了外延层 ,确定外延层的组分与晶体质量 ,并利用二次离子质谱仪进行了纵向组分分布剖析 ,利用扩展电阻仪确定外延层的电学特性。研究了锗硅应变外延层的生长特性和材料特性 ,生长速率随锗组分的增加而降低 ,以氢气为载气的硼烷对锗硅合金的生长速率有促进作用。还通过生长锗组分渐变的缓冲层 ,改善了外延层的晶体质量