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

Crystals ◽  
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.

A Comparative Study of GaN Films Grown on Different Faces of Sapphire by ECR-Assisted MBE

1992 ◽  
Vol 242 ◽  
Author(s):  
T. D. Moustakas ◽  
R. J. Molnar ◽  
T. Lei ◽  
G. Menon ◽  
C. R. Eddy
Keyword(s):  
Surface Morphology ◽  
Low Temperatures ◽  
Smooth Surface ◽  
Growth Process ◽  
X Ray Diffraction ◽  
Epitaxial Relationship ◽  
X Ray ◽  
Sapphire Substrates ◽  
Growth Method ◽  
Step Growth

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.

scholarly journals Void Shapes Controlled by Using Interruption-Free Epitaxial Lateral Overgrowth of GaN Films on Patterned SiO2AlN/Sapphire Template

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Yu-An Chen ◽  
Cheng-Huang Kuo ◽  
Li-Chuan Chang ◽  
Ji-Pu Wu
Keyword(s):  
Electron Microscopy ◽  
Epitaxial Lateral Overgrowth ◽  
Threading Dislocation ◽  
X Ray Diffraction ◽  
Air Voids ◽  
X Ray ◽  
Lateral Overgrowth ◽  
Transmission Electron ◽  
Gan Film ◽  
Scanning Electron

GaN epitaxial layers with embedded air voids grown on patterned SiO2AlN/sapphire templates were proposed. Using interruption-free epitaxial lateral overgrowth technology, we realized uninterrupted growth and controlled the shape of embedded air voids. These layers showed improved crystal quality using X-ray diffraction and measurement of etching pits density. Compared with conventional undoped-GaN film, the full width at half-maximum of the GaN (0 0 2) and (1 0 2) peaks decreased from 485 arcsec to 376 arcsec and from 600 arcsec to 322 arcsec, respectively. Transmission electron microscopy results showed that the coalesced GaN growth led to bending threading dislocation. We also proposed a growth model based on results of scanning electron microscopy.

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

1994 ◽  
Vol 341 ◽  
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.

Heteroepitaxy of GaAs on Si by MOCVD

1987 ◽  
Vol 91 ◽  
Author(s):  
Tetsuo Soga ◽  
Toru Imori ◽  
Masayoshi Umeno
Keyword(s):  
Curvature Radius ◽  
Stress And Strain ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gaas On Si ◽  
Intermediate Layers ◽  
Growth Method ◽  
Step Growth

ABSTRACTThe stress and strain of GaAs on Si grown by using strained superlattice intermediate layers and a two-step growth method are characterized by the photoluminescence, X-ray diffraction and the curvature radius. The strain of GaAs grown using strained superlattice intermediate layers is smaller than that grown by the two-step growth method.

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

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).

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

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.

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

Coatings ◽  
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).

scholarly journals Dislocation Arrangement in a Thick LEO GaN Film on Sapphire

2000 ◽  
Vol 5 (S1) ◽  
pp. 97-103
Author(s):  
Kathleen A. Dunn ◽  
Susan E. Babcock ◽  
Donald S. Stone ◽  
Richard J. Matyi ◽  
Ling Zhang ◽  
...  
Keyword(s):  
High Resolution ◽  
Electron Diffraction ◽  
Threading Dislocations ◽  
X Ray Diffraction ◽  
Burgers Vector ◽  
X Ray ◽  
The Third ◽  
Dislocation Arrangement ◽  
Image Position ◽  
Gan Film

Diffraction-contrast TEM, focused probe electron diffraction, and high-resolution X-ray diffraction were used to characterize the dislocation arrangements in a 16µm thick coalesced GaN film grown by MOVPE LEO. As is commonly observed, the threading dislocations that are duplicated from the template above the window bend toward (0001). At the coalescence plane they bend back to lie along [0001] and thread to the surface. In addition, three other sets of dislocations were observed. The first set consists of a wall of parallel dislocations lying in the coalescence plane and nearly parallel to the substrate, with Burgers vector (b) in the (0001) plane. The second set is comprised of rectangular loops with b = 1/3 [110] (perpendicular to the coalescence boundary) which originate in the coalescence boundary and extend laterally into the film on the (100). The third set of dislocations threads laterally through the film along the [100] bar axis with 1/3<110>-type Burgers vectors These sets result in a dislocation density of ∼109 cm−2. High resolution X-ray reciprocal space maps indicate wing tilt of ∼0.5º.

Defect Reduction in Cd1-xZnxTe Epilayers on GaAs Substrates

1994 ◽  
Vol 299 ◽  
Author(s):  
Saket Chadda ◽  
Kevin Malloy ◽  
John Reno
Keyword(s):  
Threading Dislocation ◽  
Full Width ◽  
X Ray Diffraction ◽  
Defect Reduction ◽  
X Ray ◽  
Gaas Substrates ◽  
Transmission Electron ◽  
Threading Dislocation Density ◽  
Optimum Period ◽  
Bulk Alloys

AbstractCd0.91Zn0.09Te/CdTe multilayers of various period thicknesses were inserted into Cd0.955Zn0.045Te bulk alloys grown on (001) GaAs. The net strain of the multilayer on the underlying Cd0.955Zn0.045Te was designed to be zero. X-ray diffraction full width at half maximum (FWHM) was used as a means to optimize the period thickness of the multilayer. Transmission electron microscopy of the optimum period thickness samples demonstrated four orders of magnitude decrease in the threading dislocation density. Mechanism of bending by equi-strained multilayers is discussed.

Synthesis, Structure and Magnetism of ErCoIn5

2004 ◽  
Vol 848 ◽  
Author(s):  
Evan Lyle Thomas ◽  
Erin E. Erickson ◽  
Monica Moldovan ◽  
David P. Young ◽  
Julia Y. Chan
Keyword(s):  
Magnetic Properties ◽  
Electrical Resistivity ◽  
Magnetic Susceptibility ◽  
Single Crystal ◽  
Experimental Results ◽  
Flux Growth ◽  
X Ray Diffraction ◽  
Metallic Behavior ◽  
X Ray ◽  
Growth Method

AbstractA new member of the LnMIn5 family, ErCoIn5, has been synthesized by a flux-growth method. The structure of ErCoIn5 was determined by single crystal X-ray diffraction. It crystallizes in the tetragonal space group P4/mmm, Z = 1, with lattice parameters a = 4.5400(4) and c = 7.3970(7) Å, and V = 152.46(2) Å3. Electrical resistivity data show metallic behavior. Magnetic susceptibility measurements show this compound to be antiferromagnetic with TN = 5.1 K. We compare these experimental results with those of LaCoIn5 in an effort to better understand the effect of the structural trends observed on the transport and magnetic properties.

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