Improvement of Inp-GaAs-Si Quality by Thermal-Cycle Growth

1990 ◽  
Vol 198 ◽  
Author(s):  
S.M. Vernon ◽  
C.J. Keavney ◽  
E.D. Gagnon ◽  
N.H. Karam ◽  
N.M. Haegel ◽  
...  
Keyword(s):  
Thermal Cycle ◽  
Chemical Vapor ◽  
Defect Reduction ◽  
Thermal Cycle Annealing ◽  
Transmission Electron ◽  
Cycle Growth ◽  
Crystal Films ◽  
Photoluminescence Lifetime ◽  
Hall Effect Measurements ◽  
Inp Substrates

ABSTRACTSingle-crystal films of InP have been deposited on GaAs, GaAs-coated Si, and InP substrates by metalorganic chemical vapor deposition (MOCVD). Defect-reduction schemes involving various thermal annealing recipes have been developed and characterized. Material quality has been assessed by a variety of methods including transmission electron microscopy, X-ray rocking curve analysis, low-temperature photoluminescence, lifetime measurements, Hall-effect measurements, electrochemical profiling, and Nomarski microscopy. The use of either a thermal-cycle-growth or a thermal-cycle-annealing process leads to heteroepitaxial InP film quality which is significantly improved over that of its as-grown state, with the thermal-cycle growth appearing to be the more effective technique.

Growth and Characterization of InP/GaAs on Soi by Mocvd

1990 ◽  
Vol 198 ◽  
Author(s):  
N.H. Karam ◽  
V. Haven ◽  
S.M. Vernon ◽  
F. Namavar ◽  
N. El-Masry ◽  
...  
Keyword(s):  
Thermal Cycle ◽  
Defect Density ◽  
Photoluminescence Intensity ◽  
Defect Reduction ◽  
Reduction Techniques ◽  
Thermal Cycle Annealing ◽  
Cycle Growth ◽  
Order Of Magnitude ◽  
First Time

ABSTRACTEpitaxial InP films have been successfully deposited on GaAs coated silicon wafers with a buried oxide for the first time by MOCVD. The SOI wafers were prepared using the Separation by IMplantation of Oxygen (SIMOX) process. The quality of InP on SIMOX is comparable to the best of InP on Si deposited in the same reactor. Preliminary results on defect reduction techniques such as Thermal Cycle Growth (TCG) show an order of magnitude increase in the photoluminescence intensity and a factor of five reduction in the defect density. TCG has been found more effective than Thermal Cycle Annealing (TCA) in improving the crystalline perfection and optical properties of the deposited films.

RBS/Chainneling and Ten Analysis of Heteroepitaxial Ge Films on GaAs Crown by Remote Plasma Enhanced Chemical Vapor Deposition

1987 ◽  
Vol 102 ◽  
Author(s):  
N.R. Parikh ◽  
F V Hattangady ◽  
J.B. Posthill ◽  
M.L. King ◽  
R.A. Rudder ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Microstructural Characterization ◽  
Gaas Crystal ◽  
Remote Plasma ◽  
Transmission Electron ◽  
Crystal Films ◽  
Substrate Temperatures ◽  
Minimum Yield

ABSTRACTWe have deposited thin Ge films on GaAs(111) crystals over a temperature range of 250-400° C by Remote Plasma Enhanced Chemical Vapor Deposition (RPECVD). Rutherford Backscattering (RBS)/channelinf analysis of these heteroepitaxial films were carried out using 2.07 MeV He ions channeled along the <111> axis. RBS/channeling analysis showed that the best Ce films were grown at a substrate temperature of 300° C. The minimum yield for <111> channeling on films deposited at 300° C was 0.08, slightly greater than that of the GaAs crystal. Films grown at temperatures below 300° C showed poor epitaxy. No channeling was observed for the film grown at 250° C. Films grown at substrate temperatures above 350° C showed high dechanneling near the interface and poor epitaxy indicating films are highly defective. The RBS/channeling results are correlated with microstructural characterization using transmission electron microscopy of these films.

Interface Effects with Ga0.47In0.53As Layers on InP Substrates Prepared by Organometallic Chemical Vapor Deposition

1982 ◽  
Vol 18 ◽  
Author(s):  
J. S. Whiteley ◽  
S. K. Ghandhi
Keyword(s):  
Chemical Vapor Deposition ◽  
Hall Effect ◽  
Electron Concentration ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Hall Effect Measurements ◽  
Inp Substrates ◽  
Lattice Matched ◽  
Interface Effects

Lattice-matched Ga0.47In0.53As was epitaxially grown on InP substrates by the reaction of triethylgallium, triethylindium and arsine. The mobility and carrier concentration in these layers were determined by sequential etch and Hall effect measurements made on the grown layers. These measurements show a considerable fall–off in mobility in the vicinity of the interface, accompanied by a rapid increase in electron concentration. In situ chloride etching of the substrate, prior to Ga–In–As growth, is shown to reduce significantly but not eliminate these interface effects. In this paper we outline possible reasons for these effects, based on measurements made on films grown with and without substrate etching and also on measurements of the effect of etching on the substrate itself.

Low Pressure Omcvd Growth of GaAs on InP for Fet and Quantum Well Laser Fabrication

1989 ◽  
Vol 145 ◽  
Author(s):  
R. Bhat ◽  
Y-H. Lo ◽  
C. Caneau ◽  
C.J. Chang-Hasnain ◽  
B.J. Skromme ◽  
...  
Keyword(s):  
Quantum Well ◽  
Field Effect Transistors ◽  
Chemical Vapor ◽  
X Ray Diffraction ◽  
Single Quantum Well ◽  
Cross Sectional ◽  
Transmission Electron ◽  
Buried Heterostructure ◽  
Step Growth ◽  
Inp Substrates

AbstractGallium arsenide epitaxial layers with excellent morphology have been grown by organometallic chemical vapor deposition (OMCVD) on (100) and 2-3° off (100) InP substrates by a modified two-step growth commonly used for GaAs on Si. The layers have been characterized by X-ray diffraction, cross-sectional transmission electron microscopy (TEM), low temperature photoluminescence (PL) and Hall measurements. 1 µm gate GaAs metal-semiconductor field effect transistors (MESFETs) with transconductances as high as 220 mS/mm have been fabricated. These MESFETs have been integrated with buried heterostructure and V-groove InGaAsP lasers. The V-groove laser -MESFET OEIC transmitter has been shown to be capable of direct modulation at 5 Gb/sec bit rate. Finally we have also demonstrated GaAs single quantum well lasers with threshold currents as low as 800 A/cm2for 50 µm wide broad area gain guided devices with 1.25 mm long cavities.

Defect Reduction in GaAs Grown on Si by Using Saw-Tooth-Patterned Substrates

1992 ◽  
Vol 281 ◽  
Author(s):  
Jane G. Zhu ◽  
M. M. Al-Jassim ◽  
N. H. Karam ◽  
K. M. Jones
Keyword(s):  
Dislocation Density ◽  
Chemical Vapor ◽  
Growth Front ◽  
Organic Chemical ◽  
Threading Dislocation ◽  
Defect Reduction ◽  
Dislocation Configuration ◽  
Si Substrates ◽  
Transmission Electron ◽  
Threading Dislocation Density

ABSTRACTEpitaxial GaAs layers have been grown on saw-tooth-patterned (STP) Si substrates by metal-organic chemical vapor deposition and analyzed by transmission electron microscopy. The utilization of this special interface feature is effective in suppressing the formation of antiphase boundaries and reducing the threading dislocation density. The growth of GaAs has been studied with the epilayer thicknesses ranging from several hundred angstroms to several microns. Very flat growth front on (100) plane above the STP region is observed. The dislocation density decreases very rapidly in the area farther away from the interface. The dislocation configuration at this STP interface is very different from that at the extensively studied two-dimensional planar interface.

A Novel TEM Technique for Characterizing As-Grown CVD Diamond Films

1991 ◽  
Vol 49 ◽  
pp. 956-957 ◽  
Author(s):  
Z.L. Wang ◽  
J. Bentley ◽  
R.E. Clausing ◽  
L. Heatherly ◽  
L.L. Horton
Keyword(s):  
Diamond Films ◽  
Chemical Vapor ◽  
Growth Direction ◽  
Dark Field ◽  
Growth Surface ◽  
Specimen Preparation ◽  
Transmission Electron ◽  
Diffraction Patterns ◽  
First Time ◽  
Microstructural Studies

Microstructural studies by transmission electron microscopy (TEM) of diamond films grown by chemical vapor deposition (CVD) usually involve tedious specimen preparation. This process has been avoided with a technique that is described in this paper. For the first time, thick as-grown diamond films have been examined directly in a conventional TEM without thinning. With this technique, the important microstructures near the growth surface have been characterized. An as-grown diamond film was fractured on a plane containing the growth direction. It took about 5 min to prepare a sample. For TEM examination, the film was tilted about 30-45° (see Fig. 1). Microstructures of the diamond grains on the top edge of the growth face can be characterized directly by transmitted electron bright-field (BF) and dark-field (DF) images and diffraction patterns.

TEM evaluation of graded SixGe1-x heterolayers

1991 ◽  
Vol 49 ◽  
pp. 894-895
Author(s):  
N. David Theodore ◽  
Mamoru Tomozane ◽  
Ming Liaw
Keyword(s):  
Heterojunction Bipolar Transistors ◽  
Gas Flow ◽  
Field Effect Transistors ◽  
Chemical Vapor ◽  
Dark Field ◽  
Bipolar Transistors ◽  
Structural Quality ◽  
Weak Beam ◽  
Transmission Electron ◽  
And Behavior

There is extensive interest in SiGe for use in heterojunction bipolar transistors. SiGe/Si superlattices are also of interest because of their potential for use in infrared detectors and field-effect transistors. The processing required for these materials is quite compatible with existing silicon technology. However, before SiGe can be used extensively for devices, there is a need to understand and then control the origin and behavior of defects in the materials. The present study was aimed at investigating the structural quality of, and the behavior of defects in, graded SiGe layers grown by chemical vapor deposition (CVD).The structures investigated in this study consisted of Si1-xGex[x=0.16]/Si1-xGex[x= 0.14, 0.13, 0.12, 0.10, 0.09, 0.07, 0.05, 0.04, 0.005, 0]/epi-Si/substrate heterolayers grown by CVD. The Si1-xGex layers were isochronally grown [t = 0.4 minutes per layer], with gas-flow rates being adjusted to control composition. Cross-section TEM specimens were prepared in the 110 geometry. These were then analyzed using two-beam bright-field, dark-field and weak-beam images. A JEOL JEM 200CX transmission electron microscope was used, operating at 200 kV.

Structural and electronic properties of defects in semiconductors

1995 ◽  
Vol 53 ◽  
pp. 4-5
Author(s):  
J.L. Batstone
Keyword(s):  
Semiconductor Device ◽  
Chemical Vapor ◽  
Misfit Strain ◽  
Organic Chemical ◽  
Extended Defects ◽  
Transmission Electron ◽  
Semiconductor Thin Films ◽  
Wide Range ◽  
Metal Organic ◽  
Film Substrate

The development of growth techniques such as metal organic chemical vapor deposition (MOCVD) and molecular beam epitaxy during the last fifteen years has resulted in the growth of high quality epitaxial semiconductor thin films for the semiconductor device industry. The III-V and II-VI semiconductors exhibit a wide range of fundamental band gap energies, enabling the fabrication of sophisticated optoelectronic devices such as lasers and electroluminescent displays. However, the radiative efficiency of such devices is strongly affected by the presence of optically and electrically active defects within the epitaxial layer; thus an understanding of factors influencing the defect densities is required.Extended defects such as dislocations, twins, stacking faults and grain boundaries can occur during epitaxial growth to relieve the misfit strain that builds up. Such defects can nucleate either at surfaces or thin film/substrate interfaces and the growth and nucleation events can be determined by in situ transmission electron microscopy (TEM).

Microstructures of SiC and Si3N4 with fibrous inclusions

1986 ◽  
Vol 44 ◽  
pp. 492-493
Author(s):  
N. J. Tighe ◽  
J. Sun ◽  
R.-M. Hu
Keyword(s):  
Vapor Deposition ◽  
Chemical Vapor ◽  
Crack Deflection ◽  
Fiber Bundles ◽  
High Temperature Strength ◽  
Graphite Fiber ◽  
Triple Junctions ◽  
Transmission Electron ◽  
Compact Graphite ◽  
Deposition Techniques

Particles of BN,and C are added in amounts of 1 to 40% to SiC and Si3N4 ceramics in order to improve their mechanical properties. The ceramics are then processed by sintering, hot-pressing and chemical vapor deposition techniques to produce dense products. Crack deflection at the particles can increase toughness. However the high temperature strength and toughness are determined byphase interactions in the environmental conditions used for testing. Examination of the ceramics by transmission electron microscopy has shown that the carbon and boron nitride particles have a fibrous texture. In the sintered aSiC ceramic the carbon appears as graphite fiber bundles in the triple junctions and as compact graphite particles within some grains. Examples of these inclusions are shown in Fig. 1A and B.

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