Effects of Sapphire Substrate Configurations on MBE Growth of ZnO

1999 ◽  
Vol 587 ◽  
Author(s):  
Keiichiro Sakurai ◽  
Ken Nakahara ◽  
Tetsuhiro Tanabe ◽  
Shizuo Fujita ◽  
Shigeo Fujita
Keyword(s):  
Surface Morphology ◽  
Sapphire Substrate ◽  
Film Growth ◽  
Semiconductor Devices ◽  
Optical Characteristics ◽  
Zno Films ◽  
Zno Film ◽  
Mbe Growth ◽  
Sapphire Substrates ◽  
Sensitive Factor

AbstractMBE growth of ZnO films for optical semiconductor devices was investigated on off-angled c-plane sapphire substrates. Twin crystal RHEED patterns and surface facetting observed with c-plane just-oriented substrates were suppressed by enlarging the offset angles from near-zero to 2.87 degrees. Though no significant changes were seen in optical characteristics, FWHM of XRC narrowed and surface morphology improved with larger offset angles, indicating that the offset angle is also a sensitive factor for ZnO film growth.

Growth of ZnO Thin Films on Sapphire Substrates by ECR-Assisted MBE

1997 ◽  
Vol 474 ◽  
Author(s):  
Hee-Bog Kang ◽  
Kiyoshi Nakamura ◽  
Kazuo Ishikawa
Keyword(s):  
Sapphire Substrate ◽  
Electron Cyclotron Resonance ◽  
Rf Sputtering ◽  
Zno Films ◽  
Zno Film ◽  
Epitaxial Relationship ◽  
Rocking Curve ◽  
Sapphire Substrates ◽  
Relationship Of ◽  
Ecr Source

ABSTRACTEpitaxial ZnO films were grown on c-plane sapphire substrate at low temperature using the electron cyclotron resonance-assisted molecular beam epitaxy(ECR-assisted MBE) technique. In this method, Zn vapor provided by a Knudsen cell reacts with oxygen activated in an ECR source on the surface of sapphire substrate. The crystal structure, surface morphology and epitaxial relationship of the films were investigated. It was confirmed that the ECR-assisted MBE technique was capable of growing a high quality epitaxial ZnO films on c-plane sapphire substrates at low temperatures in comparison with CVD and RF sputtering. The FWHM of an x-ray rocking curve of the (0002) peak for a 0.33μ-thick ZnO film was as narrow as 0.58°. The epitaxial relationship between ZnO film and c-plane sapphire substrate was determined to be (0001)ZnO//(0001)Al2O3 with in-plane alignment of [1100]ZnO//[2110]Al2O3, which is equivalent to the 30° rotation of ZnO relative to sapphire in the c-plane.

Room-Temperature Deposition of ZnO Thin Films by Using DC Magnetron Sputtering

2014 ◽  
Vol 896 ◽  
pp. 237-240 ◽  
Author(s):  
Putut Marwoto ◽  
Sulhadi ◽  
Sugianto ◽  
Didik Aryanto ◽  
Edy Wibowo ◽  
...  
Keyword(s):  
Thin Films ◽  
Magnetron Sputtering ◽  
Room Temperature ◽  
Film Growth ◽  
Transparent Conductive Oxide ◽  
Zno Thin Films ◽  
Zno Films ◽  
Plasma Power ◽  
Zno Film ◽  
Dc Magnetron Sputtering

ZnO thin films have successfully been deposited using DC magnetron sputtering at room temperature by means of plasma power variation. XRD results show that films were grown at a plasma power of 30 W and 40 W are polycrystalline, while at 20 W is considered as amorphous. The optical bandgap of films are shrinkage by increasing the plasma power. The broadest transmittance range is belongs to ZnO film growth at plasma power of 40 W. The electrical conductivity of ZnO films increase from 4.02x10-7(Ωcm)-1to 8.92x10-7(Ωcm)-1once the plasma power is increased. Based on the electrical and optical properties of the films it clearly be seen that ZnO film grown at plasma power of 40 W has highest transmittance and lower electrical resistivity therefore it appropriate for transparent conductive oxide (TCO).

Microstructure of epitaxial AlN layers on sapphire substrates deposited by physical vapor deposition

2013 ◽  
Vol 1492 ◽  
pp. 129-134
Author(s):  
Sandeep Kohli ◽  
Boris Druz ◽  
Adrian Devasahayam ◽  
Arindom Datta ◽  
Frank Cerio
Keyword(s):  
Sapphire Substrate ◽  
Physical Vapor Deposition ◽  
Film Growth ◽  
Sapphire Substrates ◽  
Aln Film ◽  
Dislocation Densities ◽  
Out Of Plane ◽  
20 Nm ◽  
Edge Dislocations

ABSTRACTAsymmetric (10L) XRD peaks have been employed as a measure of epitaxial quality for aluminum nitride (AlN) nucleation layers (NL) deposited on sapphire substrate. Epitaxial AlN films have been deposited on 2-6” sapphire substrate by reactive sputtering. FWHM of AlN (103) and (105) were found to be an excellent indicator of quality of AlN films for GaN growth. AlN films produced nucleation layers with highly reproducible microstructure and GaN film growth. NLs had in-plane and out-of-plane texture as evident by the pole-figure results and selected area diffraction pattern. Based on electron microscopy results, AlN film thickness for complete atomic ordering was estimated to be 6-7 nm and most of the edge dislocations were seen in the first 20 nm of the film. Excellent thickness and texture uniformity were seen on planar and patterned sapphire substrates. A compressive stress of 2.9±0.2 GPa was seen in our BKM films. The maximum screw and edge dislocation densities of films were found to be ∼3 x 108 cm−2 and ∼9 x 109 cm−2 respectively. The root mean square roughnesses of A-polar films were found to be < 0.3 nm.

scholarly journals The Investigation of High-Temperature SAW Oxygen Sensor Based on ZnO Films

Materials ◽  
2019 ◽  
Vol 12 (8) ◽  
pp. 1235 ◽  
Author(s):  
Lin Shu ◽  
Xuemin Wang ◽  
Dawei Yan ◽  
Long Fan ◽  
Weidong Wu
Keyword(s):  
High Temperature ◽  
Surface Morphology ◽  
Gas Sensor ◽  
Oxygen Sensor ◽  
Experimental Period ◽  
Zno Films ◽  
Zno Film ◽  
Axis Orientation ◽  
Potential Applications ◽  
Oxygen Gas

In this paper, a wireless oxygen sensor based on a surface acoustic wave (SAW) was reported. For high-temperature applications, novel Al2O3/ZnO/Pt multilayered conductive film was deposited on langasite substrate as the electrodes, and ZnO film obtained by the pulse laser deposition (PLD) method was used as the sensitive film. The measurements of X-ray diffraction (XRD) and a scanning electron microscope (SEM) showed that the c-axis orientation of the ZnO grains and the surface morphology of the films were regulated by the deposition temperature. Meanwhile, the gas response of the sensor was strongly dependent on the surface morphology of the ZnO film. The experimental results showed that the oxygen gas sensor could operate at a high-temperature environment up to 850 °C with good stability for a long period. The max frequency shift of the sensors reaches 310 kHz, when exposed to 40% O2 gas at 850 °C. The calculated standard error of the sensors in a high-temperature measurement process is within 3%. Additionally, no significant signal degradation could be observed in the long-term experimental period. The prepared SAW oxygen gas sensor has potential applications in high-temperature sensing systems.

scholarly journals Aerosol assisted chemical vapour deposition of Ga-doped ZnO films for energy efficient glazing: effects of doping concentration on the film growth behaviour and opto-electronic properties

2015 ◽  
Vol 3 (24) ◽  
pp. 13039-13049 ◽  
Author(s):  
Shuqun Chen ◽  
Giorgio Carraro ◽  
Davide Barreca ◽  
Andrei Sapelkin ◽  
Wenzhi Chen ◽  
...  
Keyword(s):  
Electronic Properties ◽  
Energy Efficient ◽  
Doping Concentration ◽  
Vapour Deposition ◽  
Film Growth ◽  
Chemical Vapour ◽  
Zno Films ◽  
Zno Film ◽  
Growth Behaviour ◽  
Doped Zno

AACVD ZnO film growth as a function of doping concentration.

Towards Lower Deposition Temperatures of Spray Deposited ZnO Films

2007 ◽  
Vol 1012 ◽  
Author(s):  
Sophie E. Gledhill ◽  
Nicholas Allsop ◽  
Pablo Thier ◽  
Christian Camus ◽  
Martha Lux-Steiner ◽  
...  
Keyword(s):  
Deposition Temperature ◽  
Film Growth ◽  
Spray Deposition ◽  
Free Charge Carrier ◽  
Precursor Solution ◽  
Zno Films ◽  
Zno Film ◽  
Roll Coating ◽  
Roll To Roll ◽  
Substrate Temperatures

AbstractHighly transparent, conductive ZnO:Al doped films have been deposited by a non-vacuum spray deposition method. At substrate temperatures above 400C we attain resistivites of 5x10-3Ohmcm and free charge carrier concentrations of 10-20cm-3. ZnO film growth and quality are sensitive to the precursor solution. For a non-vacuum process the properties of the films are excellent.The challenge is to lower the deposition temperature to a maximum of 250C to be useful for Cu(In, Ga)(S, Se)2 solar cells and yet maintain the ZnO film quality and conductivity. As the deposition temperature decreases the resistivity of the ZnO drastically increases yet is conducting enough to be used undoped as the intrinsic ZnO layer. This is particularly relevant as the deposition technique is readily up-scalable to roll to roll coating processes.

X-RAY ABSORPTION SPECTROSCOPY STUDY OF THIN ZnO FILMS GROWN BY SINGLE SOURCE CVD ON Si(100)

1997 ◽  
Vol 04 (01) ◽  
pp. 39-44 ◽  
Author(s):  
M. H. KOCH ◽  
A. J. HARTMANN ◽  
R. N. LAMB ◽  
M. NEUBER ◽  
J. WALZ ◽  
...  
Keyword(s):  
Film Thickness ◽  
Absorption Spectroscopy ◽  
Film Growth ◽  
Chemical Vapor ◽  
Zno Films ◽  
Single Source ◽  
Zno Film ◽  
High Concentration ◽  
X Ray ◽  
X Ray Absorption

In situ X-ray absorption spectroscopy analysis of early states of ZnO film growth on Si(100) by single source chemical vapor deposition (CVD) has been performed using basic zinc acetate as precursor. A high concentration of carbon is detected at the interface, which decreases with increasing film thickness (~2 nm thickness), and as expected there is some oxidization of the Si surface. This is explained by the chemical nature of the immediate surface upon which the deposition takes place, varying from a reactive, clean Si surface to a less reactive, mixed oxide layer after successive deposition steps. On the latter surface, the decomposition fragments are believed to be more volatile and thus the resulting film contains less carbon contamination. The results confirm that the tetrahedral core of the central oxygen atom with four neighboring zinc atoms, which reassembles the structure in solid ZnO , is kept intact upon decomposition of the precursor on the heated Si (100) (400°C) substrate. However, no long range orientation of the ZnO tetrahedrons was found, indicating that the resulting ZnO film has no preferred crystalline structure for the film thickness investigated here (~2 nm).

Immobilization of ZnO Suspension on Glass Substrate to Remove Filtration During the Removal of Remazol Red R from Aqueous Solution

2016 ◽  
Vol 12 (6) ◽  
pp. 4127-4133
Author(s):  
Nazmul Kayes ◽  
Jalil Miah ◽  
Md. Obaidullah ◽  
Akter Hossain ◽  
Mufazzal Hossain
Keyword(s):  
Aqueous Solution ◽  
Glass Substrate ◽  
Uv Light ◽  
Aqueous Suspension ◽  
Light Irradiation ◽  
Zno Films ◽  
Light Sources ◽  
Zno Film ◽  
Semiconductor Oxides ◽  
Remazol Red

Photodegradation of textile dyes in the presence of an aqueous suspension of semiconductor oxides has been of growing interest. Although this method of destruction of dyes is efficient, the main obstacle of applying this technique in the industry is the time and cost involving separation of oxides from an aqueous suspension. In this research, an attempted was made to develop ZnO films on a glass substrate by simple immobilization method for the adsorption and photodegradation of a typical dye, Remazol Red R (RRR) from aqueous solution. Adsorption and photodegradation of  RRR were performed in the presence of glass supported ZnO film. Photodegradation of the dye was carried out by varying different parameters such as the catalyst dosage, initial concentrations of RRR, and light sources. The percentage of adsorption as well as photodegradation increased with the amount of ZnO, reaches a maximum and then decreased. Maximum degradation has been found under solar light irradiation as compared to UV-light irradiation. Removal efficiency was also found to be influenced by the pre-sonication of ZnO suspension.

Growth of Epitaxial IrSi3 Layers on Si(111)

1989 ◽  
Vol 160 ◽  
Author(s):  
T. L. Lin ◽  
C. W. Nieh
Keyword(s):  
Surface Morphology ◽  
Molecular Beam ◽  
Solid Phase ◽  
Single Mode ◽  
Growth Conditions ◽  
Tem Analysis ◽  
Mbe Growth ◽  
Good Surface ◽  
Transmission Electron

AbstractEpitaxial IrSi3 films have been grown on Si (111) by molecular beam epitaxy (MBE) at temperatures ranging from 630 to 800 °C and by solid phase epitaxy (SPE) at 500 °C. Good surface morphology was observed for IrSi3 layers grown by MBE at temperatures below 680 °C, and an increasing tendency to form islands is noted in samples grown at higher temperatures. Transmission electron microscopy (TEM) analysis reveals that the IrSi3 layers grow epitaxially on Si(111) with three epitaxial modes depending on the growth conditions. For IrSi3 layers grown by MBE at 630 °C, two epitaxial modes were observed with ~ 50% area coverage for each mode. Single mode epitaxial growth was achieved at a higher MBE growth temperature, but with island formation in the IrSi3 layer. A template technique was used with MBE to improve the IrSi3 surface morphology at higher growth temperatures. Furthermore, single-crystal IrSi3 was grown on Si(111) at 500 °C by SPE, with annealing performed in-situ in a TEM chamber.

Properties of Sputter Deposited ZnO Films Co-doped with Lithium and Phosphorus

2013 ◽  
Vol 1494 ◽  
pp. 77-82
Author(s):  
T. N. Oder ◽  
A. Smith ◽  
M. Freeman ◽  
M. McMaster ◽  
B. Cai ◽  
...  
Keyword(s):  
Rf Magnetron Sputtering ◽  
Zno Films ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sapphire Substrates ◽  
Hall Effect Measurements ◽  
Sputter Deposited ◽  
P Type ◽  
Post Deposition ◽  
Co Doped

ABSTRACTThin films of ZnO co-doped with lithium and phosphorus were deposited on sapphire substrates by RF magnetron sputtering. The films were sequentially deposited from ultra pure ZnO and Li3PO4 solid targets. Post deposition annealing was carried using a rapid thermal processor in O2 and N2 at temperatures ranging from 500 °C to 1000 °C for 3 min. Analyses performed using low temperature photoluminescence spectroscopy measurements reveal luminescence peaks at 3.359, 3.306, 3.245 eV for the co-doped samples. The x-ray diffraction 2θ-scans for all the films showed a single peak at about 34.4° with full width at half maximum of about 0.17°. Hall Effect measurements revealed conductivities that change from p-type to n-type over time.

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