Strain in Epitaxial GaAs on Si and CaF2/Si

1987 ◽  
Vol 102 ◽  
Author(s):  
L. J. Schowalter ◽  
Shin Hashimoto ◽  
G. A. Smith ◽  
W. M. Gibson ◽  
N. Lewis ◽  
...  
Keyword(s):  
Buffer Layer ◽  
Gaas Layer ◽  
Buffer Layers ◽  
Threading Dislocations ◽  
Si Substrate ◽  
High Quality ◽  
Strain Measurements ◽  
Epitaxial Gaas ◽  
Ion Channeling ◽  
Gaas On Si

ABSTRACTIn this paper, ion channeling techniques are used to show that epitaxial GaAs layers grown on vicinal Si(001) wafers do not have their [001] axis precisely aligned with that of the Si substrate. Instead, the [001] axis of the GaAs layer is found to be tilted toward the surface normal of the Si substrate. This tilt was found to be ∼0.2° on vicinal Si(001) substrates which have their [001] axis tilted 4° toward the [110] azimuth. It is speculated that this misalignment is reponsible for the residual density of threading dislocations in the GaAs on Si layer. An approach described here, which can be used to avoid strain in the GaAs layer, is to grow a CaF2 buffer layer between the Si substrate and the epitaxial GaAs layer. High quality epitaxial GaAs layers have been obtained on both CaF 2 /Si(001) and CaF 2 /Si(111) substrates. Strain measurements of the epitaxial GaAs on the CaF 2 buffer layers indicate that these layers have strains below our detection limits.

Annihilation of Threading Dislocations in Regrown GaN on Electrochemically Etched Nanoporous GaN Template with Optimization of Buffer Layer Growth

2007 ◽  
Vol 31 ◽  
pp. 227-229
Author(s):  
C.B. Soh ◽  
H. Hartono ◽  
S.Y. Chow ◽  
Soo Jin Chua
Keyword(s):  
Electron Microscopy ◽  
Buffer Layer ◽  
Electrochemical Etching ◽  
Layer Growth ◽  
Device Fabrication ◽  
Buffer Layers ◽  
Threading Dislocations ◽  
High Quality ◽  
Transmission Electron ◽  
Gan Buffer Layer

Nanoporous GaN template has been fabricated by electrochemical etching to give hexagonal pits with nano-scale pores of size 20-50 nm in the underlying grains. Electrochemical etching at The effect of GaN buffer layer grown at various temperatures from 650°C to 1015°C on these as-fabricated nano-pores templates are investigated by transmission electron microscopy. The buffer layer grown at the optimized temperature of 850°C partially fill up the pores and voids with annihilation of threading dislocations, serving as an excellent template for high-quality GaN growth. This phenomenon is, however not observed for the samples grown with other temperature buffer layers. The PL spectrum for the regrowth GaN on nanoporous GaN template also shows an enhancement of PL intensity for GaN peak compared to as-grown GaN template, which is indicative of its higher crystal quality. This makes it as a suitable template for subsequent device fabrication.

High-Quality GaAsxP1-x/In0.13Ga0.87P Quantum Well Structure Grown on Si Substrate with a Very Few Threading Dislocations

1999 ◽  
Vol 38 (Part 1, No. 12A) ◽  
pp. 6645-6649 ◽  
Author(s):  
Yasuhiro Fujimoto ◽  
Hiroo Yonezu ◽  
Satoshi Irino ◽  
Katsuya Samonji ◽  
Kenji Momose ◽  
...  
Keyword(s):  
Quantum Well ◽  
Threading Dislocations ◽  
Si Substrate ◽  
High Quality ◽  
Quantum Well Structure

Improved MOCVD Growth of GaAs on Si

1987 ◽  
Vol 91 ◽  
Author(s):  
R.M. Lum ◽  
J.K. Klingert ◽  
B.A. Davidson ◽  
M.G. Lamont
Keyword(s):  
Buffer Layer ◽  
Rutherford Backscattering Spectrometry ◽  
Growth Parameters ◽  
Buffer Layers ◽  
Double Crystal ◽  
Gaas On Si ◽  
Mocvd Growth ◽  
Gaas Films ◽  
Gaas Buffer Layer ◽  
Direct Growth

ABSTRACTIn the direct growth of GaAs on Si by MOCVD the overall quality of the heteroepitaxial film is controlled to a large extent by the growth parameters of the initial GaAs buffer layer. We have investigated the structural properties of this layer using Rutherford Backscattering Spectrometry (RBS) and X-ray double crystal diffractometry. The crystallinity of the buffer layer was observed to improve with increasing layer thickness in the range 10–100nm, and then to rapidly degrade for thicker layers. High temperature (750°C) annealing of the buffer layers resulted in considerable reordering of all but the thicker (>200 nm) layers. Alteration of the usual GaAs/Si growth sequence to include an in-situ anneal of the buffer layer after growth interruption yielded GaAs films with improved structural, optical and electrical properties.

Effect of LaNiO3 Buffer Layer on the Electrical and Optical Properties of Nonpolar ZnO Film Deposited on (100) Si Substrate

2019 ◽  
Vol 793 ◽  
pp. 29-34
Author(s):  
Quan Liang Zhao ◽  
Tian Yu Sheng ◽  
Lei Pang ◽  
Jie Jian Di ◽  
Guang Ping He ◽  
...  
Keyword(s):  
Buffer Layer ◽  
Buffer Layers ◽  
Zno Films ◽  
Band Edge Emission ◽  
X Ray Diffraction ◽  
Zno Film ◽  
Si Substrate ◽  
Radio Frequency Sputtering ◽  
Silicon Based ◽  
Current Behavior

Nonpolar ZnO films are deposited on (100) Si substrate using LaNiO3 conducting buffer layer by radio frequency sputtering. X-ray diffraction results show that ZnO films are (110) and (002) orientation with and without LaNiO3 buffer layer. The current behavior of ZnO/LaNiO3 heterojunction exhibits ohmic conduction which is different from the diode-like rectification current behavior of ZnO film using insulated buffer layers. The photoluminescence properties indicate that the (110)-oriented nonpolar ZnO film has better band-edge emission than that of (002)-oriented polar ZnO film. It is suggested that LaNiO3 buffer layer can be used to deposit silicon-based ZnO film with well ohmic contact electrode in optoelectronic devices.

Reduction of Dislocation Density in GaAs on Si Substrate by Si Interlayer and Initial Si Buffer Layer

1991 ◽  
Vol 30 (Part 2, No. 3B) ◽  
pp. L447-L450 ◽  
Author(s):  
Akihiro Hashimoto ◽  
Naoharu Sugiyama ◽  
Masao Tamura
Keyword(s):  
Dislocation Density ◽  
Buffer Layer ◽  
Si Substrate ◽  
Gaas On Si

Strain Measurements in Si/Si0.5Ge0.5 Superlattices by He Ion Channeling

1987 ◽  
Vol 91 ◽  
Author(s):  
S. Mantl ◽  
E. Kasper ◽  
H. J. Jorke
Keyword(s):  
Buffer Layer ◽  
Elastic Energy ◽  
Molecular Beam ◽  
Stable Structure ◽  
Strain Fields ◽  
Strain Measurements ◽  
Ion Channeling

ABSTRACTHe ion channeling experiments have been performed on molecular beam grown Si/SiGe superlattices to determine the strain fields. Angular yield scans provide directly the tetragonal strains in the layers. In Si/Si0.5Ge0.5 superlattices grown on (100) Si only the SiGe layers are strained. Almost equal but opposite strains in the Si and SiGe layers have been found in a Si/Si0.5Ge0.5 superlattice deposited on a 230 nm thick SiO.71Ge0.29 buffer layer. Strain symmetrization yields the minimum elastic energy and thus to the most stable structure.

Growth and properties of epitaxial PbSe on Si(111) and Si(100) without buffer layer

1995 ◽  
Vol 379 ◽  
Author(s):  
P. Müller ◽  
A.N. Tiwari ◽  
H. Zogg
Keyword(s):  
Buffer Layer ◽  
Lattice Mismatch ◽  
Infrared Detector ◽  
Device Fabrication ◽  
Buffer Layers ◽  
Silicon Substrates ◽  
High Quality ◽  
Si Substrates ◽  
Large Lattice ◽  
Large Lattice Mismatch

Narrow gap IV-VI materials like PbS, PbSnSe and PbSnTe are used for infrared detector device fabrication [1,2]. Earlier an intermediate Ila-fluoride buffer layer, which consisted of a BaF2/CaF2-stack of about 2000 Å thickness, was used to get epitaxial high quality layers on silicon substrates. This buffer is now reduced to a much thinner layer of only about 20 Å thick CaF2, regardless the large lattice mismatch between layer and substrate [3,4,5]. The question therefore arises if high quality IV-VI layers can be grown on Si-substrates without any buffer layer as e.g. in CdTe/Si or GaAs/Si systems.The aim of this work is to grow IV-VI layers directly on Si-substrates without any buffer layers to study the growth kinetics and epitaxial quality. PbSe was chosen as a representant of IV-VI materials, and layers were grown on (111)- and (100)-oriented silicon substrates.

High quality GaAs on Si using Si0.04Ge0.96/Ge buffer layers

1991 ◽  
Vol 107 (1-4) ◽  
pp. 489-493 ◽  
Author(s):  
R. Venkatasubramanian ◽  
M.L. Timmons ◽  
J.B. Posthill ◽  
B.M. Keyes ◽  
R.K. Ahrenkiel
Keyword(s):  
Buffer Layers ◽  
High Quality ◽  
Gaas On Si

scholarly journals Growth Of High Quality GaN Thin Films By MBE On Intermediate-temperature Buffer Layers

2000 ◽  
Vol 5 (1) ◽  
Author(s):  
W.K. Fong ◽  
C. F. Zhu ◽  
B. H. Leung ◽  
Charles Surya
Keyword(s):  
Low Temperature ◽  
Buffer Layer ◽  
Electron Mobility ◽  
Unique Feature ◽  
Growth Conditions ◽  
Intermediate Temperature ◽  
Buffer Layers ◽  
Rf Plasma ◽  
Epitaxial Layers ◽  
High Quality

We report the growth of high quality GaN epitaxial layers by rf-plasma MBE. The unique feature of our growth process is that the GaN epitaxial layers are grown on top of a double layer that consists of an intermediate-temperature buffer layer (ITBL), which is grown at 690°C and a conventional low-temperature buffer layer deposited at 500°C. It is observed that the electron mobility increases steadily with the thickness of the ITBL, which peaks at 377 cm2V−1s−1 for an ITBL thickness of 800 nm. The PL also demonstrated systematic improvements with the thickness of the ITBL. Our analyses of the mobility and the photoluminescence characteristics demonstrate that the utilization of an ITBL in addition to the conventional low-temperature buffer layer leads to the relaxation of residual strain within the material resulting in improvement in the optoelectronic properties of the films. A maximum electron mobility of 430 cm2V−1s−1 can be obtained using this technique and further optimizing the growth conditions for the low-temperature buffer layer.

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