OPTICAL AND STRUCTURAL-PROPERTIES OF AP-MOVPE GAINP/GAAS HETEROSTRUCTURES

Lattice matched GaInP/GaAs heterostructures were grown by atmospheric pressure-metal organic vapor phase epitaxy (AP-MOVPE). Compositional intermixing of As/P and Ga/In near the heterointerfaces was studied by photoluminescence (PL) spectroscopy. Indium segregation, memory effect of In into GaAs and the carry-over of As in the GaInP layer during the growth process were considered as three major factors giving rise to the anomalous emissions in the PL spectra. Both thermal annealing and zinc doping strongly enhanced the compositional interdiffusion near the heterointerfaces.

Selective Area Growth InGaAsP by MOVPE

The wide stripe (ISjum) selective area growth (SAG) of InGaAsP by low pressure MOVPE is systematically investigated. The characteristics of the growth ratios,thickness enhancement factors .bandgap modulation,and composition modulation vary with the growth conditions such as mask width,growth pressure. Flux of III-group precursors are outlined and the rational mechanism behind SAG MOVPE is explained. In addition,the surface spike of the SAG InGaAsP is shown and the course of it is given by the variation of V /III .

多量子阱电吸收调制DFB激光器的一种新型LP-MOCVD对接生长方法

提出了一种提高多量子阱电吸收调制DFB-LD集成器件（EML）耦合效率的对接生长方法。采用LP-MOCVD外延方法，制作了对接方法不同的三种样片，通过扫描电镜研究它们的表面及对接界面形貌，发现新对接结构的样片具有更好的对接界面。制作出相应的三种EML管芯，从测量所得到的出光功率特性曲线，计算出不同对接方法下EML管芯的耦合效率和外量子效率。实验结果表明，这种对接生长方案，可以获得光滑的对界面，显著提高了激光器和调制器之间的耦合效率（从常规的17%提高到78％）及EML器件的外量子效率（从0.03mW/mA提高到0.15mW/mA)。

Etching Behavior of GaN/GaAs(001) Epilayers Grown by MOVPE

Wet etching characteristics of cubic GAN (c-GaN) thin films grown on GaAs(001) by metalorganic vapor phase epitaxy (MOVPE) are investigated. The samples are etched in HCl, H_3PO_4, KOH aqueous solutions, and molten KOH at temperatures in the range of 90～300 ℃. It is found that different solution produces different etch figure on the surfaces of a sample. KOH-based solutions produce rectangular pits rather than square pits. The etch pits elongate in [1(1-bar)0] direction, indicating asymmetric etching behavior in the two orthogonal <110> directions. An explanation based on relative reactivity of the various crystallographic planes is employed to interpret qualitatively the asymmetric etching behavior. In addition, it is found that KOH aqueous solution would be more suitable than molten KOH and the two acids for the evaluation of stacking faults in c-GaN epilayers.

1.5μm Self-Aligned Spotsize Converter Integrated DFB Fabricated by Selective Area Grown MOVPE

High performance 1.57μm spotsize converter monolithically integrated DFB is fabricated by the technique of self-aligned selective area growth. The upper optical confinement layer and the butt-coupled tapered thickness waveguide are regrown simultaneously, which not only offeres the separated optimization of the active region and the integrated spotsize converter, but also reduces the difficulty of the butt-joint selective regrowth. The threshold current is as low as 4.4mA. The output power at 49mA is 10.1mW. The side mode suppression ratio (SMSR) is 33.2dB. The vertical and horizontal far field divergence angles are as small as 9° and 15° respectively, the 1dB misalignment tolerance are 3.6μm and 3.4μm.

选择外延MOVPE的表面迁移

研究了采用选择外延MOVPE生长InGaAsP的组分随掩模宽度的变化规律，以及InGaAsP表面边缘尖角随V／III比的变化。结果表明，随着掩模宽度的增大，In组分增大，Ga组分减少；随着V／III比的增大，InGaAsP材料表面趋向平坦。对材料边缘尖角的变化规律作出了合理解释，研制出表面平坦的外延材料，为器件研制提供了有效的方法。

MOVPE生长InGaN/GaN单量子阱绿光LED

于2010-11-23批量导入

MOVPE生长Ga_xAl_yIn_（1-x-y）N的准热力学模型（英文）

提出一个以TMGa、TMAl、TMIn和NH_3为源，用MOVPE方法生长Ga_xAl_yIn_(1-x-y)N四元合金的推热力学模型。该模型假设四元合金是由氨和Ⅲ族元素之间反应合成的，其特点是考虑了NH_3的分解效率，并用N、H、Ga、Al及In的摩尔分数代替惯用的分压来表示质量守衡方程。计算了各种生长条件对于与GaN晶格匹配的Ga_xAl_yIn_(1-x-y)N四元合金与注入反应室的Ⅲ族金属有机化合物之间关系的影响。计算表明，几乎所有达到生长表面的Al和Ga都并入到Ga_xAl_yIn_(1-x-y)N四元合金中，而In则富集在气相。为增强铟的并入，应采用低的生长温度，高的Ⅴ/Ⅲ比，氮载气而且须要设法降低到达生长界面前氨的分解。

Quasi-Thermodynamic Model of MOVPE of InAlN

国家自然科学基金

A Quasi-Therm odynam ic Model of MOVPE of InGaN

国家863计划,国家自然科学基金

生长温度对长波长InP/AlGaInAs/InP材料LP-MOCVD生长的影响

研究不同生长温度下的InP/AlGaInAs/InP材料LP-MOCVD生长，用光致发光和X射线双晶衍射等测试手段分析了其材料特性，得到了室温脉冲激射1.3μm AlGaInAs有源区SCH-MQW结构材料，为器件制作研究打下了基础。

Quasi-Thermodynamic Model for MOVPE of AlGaN

国家863计划,国家自然科学基金

Strain Analysis of Cubic AlGaN/GaNGrownon GaAs（100） Substrate by MOVPE

于2010-11-23批量导入

掺硅氮化镓材料的MOVPE生长及其性质研究

研究了用金属有机物气相外延(MOVPE)方法在蓝宝石衬底上生长掺硅氮化镓的生长方法。发现了在硅烷掺杂剂流量较高的情况下，氮化镓的电子浓度趋于饱和现象。研究了掺硅氮化镓的电学、光学、结晶学以及表面形貌等物理性质。

Multi-Wavelength InGaAsP Lasers Grown by LP-MOCVD Selective Area Growth

国家863计划