Selective LPE-growth of ln0.53Ga0.47As on semi-insulating InP

Selective liquid phase epitaxy (SLPE) of high purity(n = 2 × 10¹⁵ cm^-3) In_0.53Ga_0.47As on SiO₂-masked (100)-InP:Fe substrates has been performed and investigated using Normarski interference contrast microscopy and SEM. The infill growth was done at low temperatures (˜ 585° C) directly into chemically (HC1:CH₃COOH:H₂O₂) etched cavities without melt-etching. Square and circular recesses of 2–3 μm depth and varying size (100-500 μm) have been used in contrast to common reported regrowth experiments in long channels. Enormously enhanced growth rates have been found within the small structures. Orientation dependent growth effects are described. The realization of selectively grown areas with flat surface morphology has been achieved which is important for optoelectronic integration. Most information contained in this paper was presented at the 27th Electronic Materials Conference, Boulder, Co., June 20, 1985.     

1990 Electronic Materials Conference

Silicon doped epitaxial layers of InP have been prepared by low pressure metalorganic chemical vapour deposition, using disilane as the source of silicon. Trimethylindium and phosphine were used as the source reactants for the growth. The doping characteristics for the epitaxial growth were investigated at substrate temperatures in the range 525–750° C and for doping levels in the range 4 × 10¹⁶−2 × 10¹⁹ cm⁻³. The results indicated that the Si doping level is proportional to the disilane flow rate. The Si incorporation rate increases with temperature, but becomes temperature-independent forT > 620° C. Comparison between Si concentrations determined by Secondary Ion Mass Spectroscopy, donor levels determined by Hall effect measurements, and optical measurements at 7 K indicates that approximately 50% of the Si in the InP is in the form of electrically inactive species. Uniform doping over 5 cm wafer dimensions has been obtained for growth atT = 625° C.     

High performance AlyGa1−yAs-GaAs-lrxGa1−xAs quantum well lasers defined by silicon-oxygen impurity-induced layer disordering

In these experiments impurity-induced layer disordering (IILD) utilizing chemical reduction of SiO₂ by Al (from Al_0.8Ga_0.2As) is employed to generate Si and O to effect layer disordering. The SiO₂-Al_0.8Ga_0.2As reaction is studied with respect to annealing ambient. By controlling the extent of disordering via As₄ overpressure, closely spaced (∼1μm) Si-O IILD buried heterostructure lasers can be optically coupled or uncoupled. Direct observation of O incorporation into the buried layers is shown using secondary ion mass spectroscopy (SIMS). The thermal stability of separate-confinement Al_yGa_1−yAs-GaAs-In_xGa_1−xAs quantum well heterostructure (QWH) laser crystals is investigated using SIMS, transmission electron microscopy (TEM), and photoluminescence (PL) measurements. The data show that the thermal stability of a strained-layer In_0.1Ga_0.9As quantum well (QW) is strongly dependent upon: (1) the layer thickness and heterointerfaces of the Al_yGa_1−yAs-GaAs waveguide layers located directly above and below the QW, (2) the type of surface encapsulant employed, and (3) the annealing ambient. Narrow single-stripe (<2μm) lasers fabricated via Si-O diffusion and layer disordering exhibit low threshold currents (I_th ∼ 4 mA) and differential quantum efficiencies,η, of 22% per facet under continuous (cw) room-temperature operation.     

InGaAsP/InP准平面异质结双极晶体管及其与光器件的集成

本文采用计算机辅助分析等方法,讨论了InGaAs/InP异质结双极晶体管(HBT)结构参数与其性能的关系.在此基础上,提出了一种准平面、双集电区HBT,及其相应的制作工艺.初步测试了器件的性能,就其与材料质量的关系作了讨论.文章还提出和制作了一种采用这种HBT为电子器件的光电子集成电路(OEIC).     

多点光纤光栅测温系统在渗流监测中的应用研究

为了监测土石坝内的渗流水的情况,提出一种多点光纤Bragg 光栅传感器(FBG)的结构,采用InGaAs光电探测器阵列探测光强的光纤光栅传感阵列的波长解调方法。根据室内实验结果,对多点光纤光栅传感系统的可行性和监测数据的可靠性进行分析, 给出用于坝体温度场监测的光纤光栅传感器波长温度响应灵敏度可达到0.0091nm/℃。工程中采用电热脉冲方式对传感器附近小范围的土壤进行加热,使其与水的温度形成一定的温差,实测结果表明可以利用光纤光栅传感器监测温度异常的方法判断是否发生渗流, 从而实现对坝体内集中渗漏点的定位和自动监测。在系统防雷击、抗干扰性方面, 采用光纤光栅传感监测系统与传统仪器相比具有明显优势。     

InP/Si键合技术研究进展

InP材料及其器件的研制是近年来研究热点之一,而键合技术又是光电子集成研究领域内一项新的制作工艺。利用键合技术结合离子注入技术可以InP薄膜及器件集成到Si衬底上,改善机械强度,降低成本,具有非常诱人的应用前景。概括地介绍了近年来InP在Si上的键合工艺及层转移技术研究进展,并对InP和Si的几种键合工艺进行了分析。降低InP和Si键合温度,进行低温键合是其发展趋势。比较几种键合技术,利用等离子活化辅助键合是降低键合温度的有效途径。     

Analysis of the propagation losses of InP/InGaAsP trench waveguides fabricated by focused ion beam

Focused ion beam was used to fabricate 2 mm-long, 4 μm-wide and 4 μm-deep multimode trench waveguides in InP/InGaAsP. An automated stitching method was developed to fabricate mm-long structures using alignment marks. The waveguides were sputtered or etched using I₂ at room temperature and 150 °C stage temperature. The propagation losses induced by the different fabrication techniques were measured and ranged between 50 and 82 dB/cm. A damaged layer with implanted Ga and the sidewall roughness are identified to be the most important causes for the losses. FIB is shown to be a single-step fabrication technique for rapid-prototyping of photonic structures in InP/InGaAsP.     

不同缓冲层对GaAs基In_(0.3)Ga_(0.7)As材料特性的影响

采用组分跳变和低温大失配缓冲层技术在GaAs衬底上外延了In0.3Ga0.7As材料。测试结果表明,采用组分跳变缓冲层生长的In0.3Ga0.7As主要依靠逐层间产生失配位错来释放应力,并导致表面形成纵横交错的Cross-hatch形貌;而采用低温大失配缓冲层技术则主要通过在低温缓冲层中形成大量缺陷来充分释放应力,并在后续外延的In0.3Ga0.7As表面没有与失配位错相关的Cross-hatch形貌出现。此外,仅需50nm厚的低温大失配缓冲层即可促使In0.3Ga0.7As中的应力完全释放,这种超薄缓冲层技术在工业批产中显得更为经济。     

Effects of spontaneous emission rates on lasing characteristics of long-wavelength (1.3 µm) GaAs-based quantum dot lasers

Data are presented characterizing the spectral emission and electroluminescence efficiency dependence on temperature of InGaAs/GaAs quantum dots that result in 1.3 μm lasing at room temperature. Efficient ground state emission is achieved at 80K, but the spontaneous efficiency decreases with increasing temperatures. The ground state spectral width is 26 meV at 80K and 31 meV at 300K. Ground state lasing is obtained over a wide range of temperatures, with an ultralow threshold current density of 14 A/cm² obtained at 80K.     

In-situ monitoring of InP(100) and GaP(100) interfaces and characterization with RDS at 20 K

MOVPE-preparation of highly ordered InP(100) and GaP(100) surfaces was monitored with in-situ reflectance difference spectroscopy (RDS). Specific ordered P-terminated and ordered cation-terminated surface reconstructions were identified with specific structured RD spectra with the highest peaks. After contamination-free transfer of the samples to UHV, RDS measurements were performed also at 20 K. The experimental RD spectrum for the In-terminated, (2×4) reconstructed InP(100) surface shows a remarkable similarity to a recently published theoretical spectrum, whereas there is only moderate similarity between the experimental RD spectrum for the (2×4) reconstructed Ga-terminated GaP(100) surface and a recently proposed theoretical spectrum.