Heteroepitaxy of GaAs on Si by MOCVD

ABSTRACTGaN films were grown on c-plane (0001), a-plane (1120) and r-plane (1102) sapphire substrates by the ECR-assisted MBE method. The films were grown using a two-step growth process, in which a GaN buffer is grown first at relatively low temperatures and the rest of the film is grown at higher temperatures. RHEED studies indicate that this growth method promotes lateral growth and leads to films with smooth surface morphology. The epitaxial relationship to the substrate, the crystalline quality and the surface morphology were investigated by RHEED, X-ray diffraction and SEM studies.

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Epitaxial Relationships and Electrical Properties of SrTiO3 Films on Various Thin -Fluoride/Si Structures

MRS Proceedings ◽

10.1557/proc-341-113 ◽

1994 ◽

Vol 341 ◽

Cited By ~ 1

Author(s):

B. K. Moon ◽

H. Ishiwara

Keyword(s):

Buffer Layer ◽

Buffer Layers ◽

Breakdown Field ◽

X Ray Diffraction ◽

Dielectric Characteristics ◽

X Ray ◽

Si Substrates ◽

Initial Stage ◽

Growth Method ◽

Step Growth

AbstractCrystalline strontium titanate (SrTiO3:STO) films were grown on Si(111) and Si(100) substrates using thin SrF2 and CaF2 buffer layers by two-step growth method. In all cases, fluoride buffer layers were effective in growing STO films on Si substrates, which is probably due to that fluoride buffer layers have excellent crystallinity and they can prevent formation of amorphous SiO2 layers on Si substrates at the initial stage of the STO deposition. It was found from X-ray diffraction and pole-figure measurements that (110)-oriented STO crystallites with three different positions to the substrate were grown on Si(111) substrates for both SrF2 and CaF2 buffer layers. In constrast, (100)-oriented STO films with 12-fold symmetry were grown on a SrF2/Si(100), and mixed (110)- and (100)-oriented STO crystallites were grown on a CaF2/Si(100) structure. It was concluded from these results that better crystallinity of STO films can be obtained on the SrF2 buffer layer in case of Si(111) and on the CaF2 buffer layer in case of Si(100). It was also found from I-V and C-V analyses that the STO films have good insulating and dielectric characteristics. For a SrTiO3 film on SrF2/Si(111) structure, the best values of breakdown field (at l.μA/cm2), resistivity (at IMV/cm) and dielectric constant were 2.3MV/cm, 8.2 × 1012 Ωcm and 72, respectively.

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The Study of CIGS Absorption Layer Grown by Two-Step Growth Method for Thin-Film Solar Cell

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.418.238 ◽

2013 ◽

Vol 418 ◽

pp. 238-241

Author(s):

Li Zen Hsieh ◽

Xi Ming Duan ◽

Ming Jer Jeng

Keyword(s):

Thin Film ◽

Energy Dispersive Spectrometer ◽

Thin Film Solar Cells ◽

X Ray Diffraction ◽

X Ray ◽

Absorption Layer ◽

Growth Method ◽

Thermal Evaporator ◽

Step Growth ◽

Selenization Process

Two-step growth method was used for CuInGaSe2,(CIGS) absorption layer in this study. The layer was first deposited by thermal evaporator to use indium and gallium sauces at a vacuum of 5 × 10-6 torr and secondly, the deposited thin film was enclosed in a quartz cartridge for the first selenization. The second selenization process was coated by copper and then annealed again in a furnace. Finding best precursor for thin film solar cells was analyzed by scanning electron microscope (SEM), X-ray diffraction analyzer (XRD) and energy dispersive spectrometer (EDS).

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Scallion-Root-Shaped GaN Nanorods Grown by Two-Step Method and Study on their Properties

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.652-654.197 ◽

2013 ◽

Vol 652-654 ◽

pp. 197-201

Author(s):

Yu Ping Cao ◽

Hai Bo Sun

Keyword(s):

High Purity ◽

Photoelectron Spectroscopy ◽

Low Cost ◽

Hexagonal Wurtzite Structure ◽

X Ray Diffraction ◽

Step Method ◽

X Ray ◽

Band Emission ◽

Growth Method ◽

Step Growth

Two-step growth technology to successfully synthesize scallion-root-shaped GaN nanorods was presented in this paper. This growth method is applicable to continuous synthesis a large number of single-crystalline GaN nanorods with a high purity at a low cost. X-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) are employed to characterize the structure, composition and morphology of as-grown GaN nanorods. The results show that the obtained nanorods are single-crystal GaN with hexagonal wurtzite structure and have a relatively high purity. The diameter of the nanorods is about 500nm with length up to several tens of micrometers. The representative photoluminescence spectra (PL) measured at room temperature exhibited a strong and broad emission peak at 388nm corresponding to the strong-band-emission in wurtzite GaN, indicating that the nanorods have a good emission property. The growth mechanism is also briefly discussed.

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Growth of High Quality GaN on Si (111) Substrate by Using Two-Step Growth Method for Vertical Power Devices Application

Crystals ◽

10.3390/cryst11030234 ◽

2021 ◽

Vol 11 (3) ◽

pp. 234

Author(s):

Jae-Hoon Lee ◽

Ki-Sik Im

Keyword(s):

Reference Sample ◽

Threading Dislocation ◽

X Ray Diffraction ◽

Power Devices ◽

X Ray ◽

Growth Method ◽

Step Growth ◽

Gan On Si ◽

Growth Methods ◽

Gan Film

A crack-free GaN film grown on 4-inch Si (111) substrate is proposed using two-step growth methods simply controlled by both III/V ratio and pressure. Two-step growth process is found to be effective in compensating the strong tensile stress in the GaN layer grown on Si substrate. The high-resolution X-ray diffraction (XRD) rocking curves of (002) and (102) planes for the GaN epitaxial layer with two-step growth method are 317 and 432 arcsec, while the corresponding values for the reference sample without two-step growth method are 550 and 1207 arcsec, respectively. The reduced threading dislocation of GaN film with two-step growth method is obtained to be ~2 × 108/cm2, which is attributed to effectively annihilate and bend threading dislocation.

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Influence of Growth Temperature of the Nucleation Layer on the Growth of InP on Si (001)

Coatings ◽

10.3390/coatings9120823 ◽

2019 ◽

Vol 9 (12) ◽

pp. 823

Author(s):

Shizheng Yang ◽

Hongliang Lv ◽

Likun Ai ◽

Fangkun Tian ◽

Silu Yan ◽

...

Keyword(s):

Growth Temperature ◽

Wafer Level ◽

X Ray Diffraction ◽

Nucleation Layer ◽

Force Microscopy ◽

Gas Source ◽

Atomic Force ◽

Growth Method ◽

Step Growth ◽

Microscopy Images

InP layers grown on Si (001) were achieved by the two-step growth method using gas source molecular beam epitaxy. The effects of growth temperature of nucleation layer on InP/Si epitaxial growth were investigated systematically. Cross-section morphology, surface morphology and crystal quality were characterized by scanning electron microscope images, atomic force microscopy images, high-resolution X-ray diffraction (XRD), rocking curves and reciprocal space maps. The InP/Si interface and surface became smoother and the XRD peak intensity was stronger with the nucleation layer grown at 350 °C. The Results show that the growth temperature of InP nucleation layer can significantly affect the growth process of InP film, and the optimal temperature of InP nucleation layer is required to realize a high-quality wafer-level InP layers on Si (001).

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Strain, Stress, and Magnetic Surfaceanisotropy of Epitaxial FE(110)/MO (110) Multilayers

MRS Proceedings ◽

10.1557/proc-317-439 ◽

1993 ◽

Vol 317 ◽

Cited By ~ 1

Author(s):

R.M. Osgood ◽

B.M. Clemens ◽

R.L. White ◽

S. Brennan

Keyword(s):

Strain State ◽

Single Layer ◽

Grazing Incidence ◽

Magnetic Surface ◽

Stress And Strain ◽

Surface Anisotropy ◽

X Ray Diffraction ◽

X Ray ◽

Plane Direction ◽

Strain Stress

ABSTRACTGrazing incidence and asymmetric X-ray diffraction were used to measure the stress and strain state of Fe(110)/Mo(110) Multilayers. The highest stress in the Fe constituent of the multilayer was along the [110] in-plane direction and was due to interaction with the substrate. The Magnetic anisotropy of the Fe Multilayer constituent was measured and the magnetic surface anisotropy, which favored in-plane [001] magnetization, was deduced. In contrast, the magnetic surface anisotropy of a single layer of Fe on W preferred in-plane [110] magnetization, in agreement with the Néel Model.

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Strain Measurement by X-ray Diffraction Methods

Aeronautical Quarterly ◽

10.1017/s0001925900000160 ◽

1949 ◽

Vol 1 (3) ◽

pp. 211-224

Author(s):

G. B. Greenough

Keyword(s):

Strain Measurement ◽

Plastic Anisotropy ◽

Stress And Strain ◽

Routine Method ◽

X Ray Diffraction ◽

Strain Measurements ◽

X Ray ◽

The Past ◽

Polycrystalline Metals ◽

The Individual

SummaryMany papers have been written on the measurement of strain by X-ray diffraction methods and on the interpretation of these strains in terms of stresses. Whereas, during the past few years, the experimental methods of determining the strains have. remained largely unchanged, research has shown that the older techniques for calculating stresses from strains are not always valid.In this paper an attempt is made to describe some of the principles of strain measurement by X-ray diffraction methods to those who are unfamiliar with the methods. The types of stress and strain systems which may exist in polycrystalline metals are then considered, particular attention being paid to the effect of the elastic and plastic anisotropy of the individual crystals. Some indication is given as to how the earlier methods of interpreting X-ray strain measurements should be modified, but no rigid routine method is proposed for use in a general case.

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Microscopic Stress and Strain Evolved in a Twinning-Induced Plasticity Fe-Mn-C Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.996.135 ◽

2014 ◽

Vol 996 ◽

pp. 135-140

Author(s):

Shigeru Suzuki ◽

Shigeo Sato ◽

Koji Hotta ◽

Eui Pyo Kwon ◽

Shun Fujieda ◽

...

Keyword(s):

Strain Distribution ◽

Crystal Orientation ◽

Fem Simulation ◽

Tensile Loading ◽

Stress And Strain ◽

X Ray Diffraction ◽

Principal Stresses ◽

Orientation Data ◽

Tensile Direction ◽

X Ray

White X-ray diffraction with micro-beam synchrotron radiation was used to analyze microscopic stress evolved in coarse grains of a twinning-induced plasticity Fe-Mn-C steel under tensile loading. In addition, electron backscatter diffraction (EBSD) was used to determine the crystal orientation of grains in the polycrystalline Fe-Mn-C steel. Based on these orientation data, the stress and strain distribution in the microstructure of the steel under tensile loading was estimated using FEM simulation where the elastic anisotropy or the crystal orientation dependence of the elasticity was taken into account. The FEM simulation showed that the strain distribution in the microstructure depends on the crystal orientation of each grain. The stress analysis by the white X-ray diffraction indicated that the direction of the maximum principal stresses at measured points in the steel under tensile loading are mostly oriented toward the tensile direction. This is qualitatively consistent with the results of by the FEM simulation, although absolute values of the principal stresses may contain the effect of heterogeneous plastic deformation on the stress distribution.

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