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Showing papers on "Thin film published in 1991"


Book
01 Jan 1991
TL;DR: A review of materials science can be found in this paper, where the authors describe the properties of thin-film materials and their applications in the following categories: electrical and magnetic properties, optical properties, and material properties.
Abstract: A Review of Materials Science. Vacuum Science and Technology. Physical Vapor Deposition. Chemical Vapor Deposition. Film Formation and Structure. Characterization of Thin Films. Epitaxy. Interdiffusion and Reactions in Thin Films. Mechanical Properties of Thin Films. Electrical and Magnetic Properties of Thin Films. Optical Properties of Thin Films. Metallurgical and Protective Coatings. Modification of Surfaces and Films. Emerging Thin-Film Materials and Applications. Appendixes. Index.

3,257 citations


Journal ArticleDOI
TL;DR: Amorphous films having a component of the stoichiometric GeTe-Sb2Te3 pseudobinary alloy system were found to have featuring characteristics for optical memory material presenting a large optical change and enabling high-speed one-beam data rewriting as mentioned in this paper.
Abstract: Amorphous films having a component of the stoichiometric GeTe‐Sb2Te3 pseudobinary alloy system, GeSb2Te4 or Ge2Sb2Te5 representatively, were found to have featuring characteristics for optical memory material presenting a large optical change and enabling high‐speed one‐beam data rewriting. The material films being sandwiched by heat‐conductive ZnS layers can be crystallized (low power) or reamorphized (high power) by laser irradiation of very short duration, less than 50 ns. The cooling speed of the sandwiched film is extremely high: more than 1010 deg/s, which permits the molten material to convert to the amorphous state spontaneously; whereas, a low‐power pulse irradiation of the same duration changed the exposed portion into the crystalline state. The optical constant changes between the amorphous state and the crystalline state of them were measured to be large: from 4.7+i1.3 to 6.9+i2.6 and from 5.0+i1.3 to 6.5+i3.5, respectively. The crystallized portion was known to have a GeTe‐like fcc structure ...

1,320 citations


Journal ArticleDOI
TL;DR: A model is proposed which accounts for the formation and structure of ta-C films on the basis of the compressive stress generated by the shallow implantation of carbon ions, and an optimal range of beam energies between 15 and 70 eV, a high film stress, and a graphitic surface are predicted and confirmed by experimental evidence.
Abstract: Thin tetrahedrally coordinated amorphous carbon (ta-C) films have been grown using a filtered vacuum arc. ta-C is a new allotrope of carbon whose existence was previously thought to be unlikely. A model is proposed which accounts for the formation and structure of these films on the basis of the compressive stress generated by the shallow implantation of carbon ions. An optimal range of beam energies between 15 and 70 eV, a high film stress, and a graphitic surface are predicted and confirmed by experimental evidence. Computer simulation of the growth confirms that high compressive stress is generated by impact energies in this range.

825 citations


Journal ArticleDOI
TL;DR: In this article, the authors have grown compositionally graded GexSi1−x layers on Si at 900 °C with both molecular beam epitaxy and rapid thermal chemical vapor deposition techniques.
Abstract: We have grown compositionally graded GexSi1−x layers on Si at 900 °C with both molecular beam epitaxy and rapid thermal chemical vapor deposition techniques. Triple‐crystal x‐ray diffraction reveals that for 0.10

744 citations


Journal ArticleDOI
TL;DR: In this article, the tendency towards a specific preferred orientation is discussed on the basis of strain and surface energies, and a decrease in lattice parameter with increasing temperature was observed on annealing.

646 citations


Journal ArticleDOI
01 Aug 1991-Nature
TL;DR: In this article, a thin, single-crystal-like film of poly(tetrafluoroethylene) (PTFE) is deposited mechanically on a smooth substrate such as glass.
Abstract: THE formation of highly oriented structures such as single crystals, single-domain liquid crystals and systems comprising uniaxially oriented crystallites is important in many applications of thin films and interfaces, ranging from materials reinforcement to molecular electronics. Of the methods that exist for forming such oriented structures, however, few have sufficient generality to make them applicable to materials of differing chemical composition or physical properties. Here we present a simple and surprisingly versatile method1 for orienting a wide variety of crystalline and liquid-crystalline materials, including polymers, monomers and small organic and inorganic molecules. In our technique, a thin, single-crystal-like film of poly(tetrafluoroethylene) (PTFE) is deposited mechanically on a smooth substrate such as glass. Materials grown on this coated surface from solution, melt or vapour phases show a remarkable degree of alignment.

540 citations


Journal ArticleDOI
TL;DR: In this paper, the electronic and geometric structure of a thin oxide film grown by oxidation on NiAl(110) using electron spectroscopic techniques, i.e., LEED, EELS, XPS and ARUPS, was investigated.

512 citations


Journal ArticleDOI
TL;DR: In this article, a combination of a solid spacer layer with spectrometric analysis of reflected light from the contact enables very thin lubricant films to be accurately measured, which is applied to the study of thin films formed in rolling contacts by low viscosity lubricants.
Abstract: Optical interferometry is now a widely used technique for measuring the separating film thickness in model rolling and sliding elastohydrodynamic contacts. There are two limitations of the method as conventionally employed: first, it cannot easily be used to accurately measure films less than one quarter the wavelength of visible light, i.e. less than about 100 nm. Secondly, only certain, discrete thicknesses, spaced at least 50 nm apart can be determined. This paper describes work aimed at overcoming these limitations so as to make optical interferometry applicable to the study of boundary or very thin film elastohydrodynamic lubrication in rolling contacts. A combination of a solid spacer layer with spectrometric analysis of reflected light from the contact enables very thin lubricant films to be accurately measured. The approach is applied to the study of thin films formed in rolling contacts by low viscosity lubricants. Some anomalies in the relationship between film thickness and speed are found with...

444 citations


Journal ArticleDOI
TL;DR: In this paper, the spectral distribution of the emitted light was measured−in situ−during the anodic oxidation step, and recorded spectra show a maximum which shifts continuously from red‐orange at the beginning of the process towards the yellow range.
Abstract: Porous silicon/silicon structures under anodic oxidation conditions give rise to an electroluminescence phenomenon in the visible range. Using an optical multichannel analyzer the spectral distribution of the emitted light was measured−in situ−during the anodic oxidation step. Recorded spectra show a maximum which shifts continuously from red‐orange at the beginning of the process towards the yellow range. The visible emission well above the band gap of bulk silicon is attributed to a quantum size effect in the very small size (5–20 A) silicon island which constitutes the porous silicon skeleton. The light emission is interrupted when the current flow stops due to the formation of a continuous oxide layer at the porous silicon/silicon interface.

413 citations


Journal ArticleDOI
C. Wang1, A. Garcia1, David C. Ingram1, M. Lake1, Martin E. Kordesch1 
TL;DR: In this paper, a self-emitting CVD polycrystalline diamond film was observed to emit electrons with an intensity sufficient to form an image in the accelerating field of an emission microscope without external excitation.
Abstract: Thick (100 μm) chemical vapour deposited (CVD) polycrystalline diamond films have been observed to emit electrons with an intensity sufficient to form an image in the accelerating field of an emission microscope without external excitation (> 3 MV/m). The individual crystallites are of the order of 1–10 μm. The combined crystallite diameter and the electric field strength in these ‘self-emitting’ films are far below those typical for cold field emitters.

392 citations


Journal ArticleDOI
29 Mar 1991-Science
TL;DR: The surface microstructures of c-axis-oriented films of YBa2Cu3O7, deposited by off-axis magnetron sputtering on MgO and SrTiO3 single crystal (100) substrates, have been investigated and there is strong evidence that the films nucleate as islands and grow by adding material to the edge of a spirally rising step.
Abstract: The surface microstructures of c-axis-oriented films of YBa(2)Cu(3)O(7), deposited by off-axis magnetron sputtering on MgO and SrTiO(3) single crystal (100) substrates, have been investigated with scanning tunneling microscopy and atomic force microscopy. There is strong evidence that the films nucleate as islands and grow by adding material to the edge of a spirally rising step. This results in columnar grains, each of which contains a screw dislocation at its center. This microstructure may be of significance in determining superconducting properties such as critical current, and represents a significant difference between thin films (especially those grown in situ) and bulk materials.

Patent
19 Dec 1991
TL;DR: In this article, the authors describe a process for forming a silicon oxide film comprising the step of depositing a thin film of a silanol, a polymer thereof or a siloxane polymer, each containing an organic group, on a substrate by exciting a gas containing an organosilane or organosILoxane gas and a gas contained H and OH on the substrate in a reaction chamber to cause a reaction in a gas phase or on the substrates and removing the organic group from the thin film by plasma treatment.
Abstract: A process for forming a silicon oxide film comprising the step of depositing a thin film of a silanol, a polymer thereof or a siloxane polymer, each containing an organic group, on a substrate by exciting a gas containing an organosilane or organosiloxane gas and a gas containing H and OH on a substrate in a reaction chamber to cause a reaction in a gas phase or on the substrate and the step of removing the organic group from the thin film by plasma treatment. Preferably the thin film is formed by repeating the depositing step and the removing step in the same chamber and is heat treated at a temperature of 450 °C or below. This process provides a good insulation film having a flatness comparable to that of an SOG film.

Journal ArticleDOI
TL;DR: In this paper, the zinc blende and wurtzitic GaN films have been epitaxially grown onto (001)Si by electron cyclotron resonance microwave plasma assisted molecular beam epitaxy, using a two-step growth process.
Abstract: Zinc blende and wurtzitic GaN films have been epitaxially grown onto (001)Si by electron cyclotron resonance microwave plasma‐assisted molecular beam epitaxy, using a two‐step growth process. In this process a thin buffer layer is grown at relatively low temperatures followed by a higher temperature growth of the rest of the film. GaN films grown on a single crystalline GaN buffer have the zinc blende structure, while those grown on a polycrystalline or amorphous buffer have the wurtzitic structure.

Journal ArticleDOI
TL;DR: A model for the nucleation and growth of Co on Au(111) zigzag reconstruction geometry is proposed and a comparison with the growth of other metals on gold is given.
Abstract: The initial nucleation and the subsequent growth of Co on Au(111) have been studied with scanning tunneling microscopy. At low coverage the cobalt nucleates forming polygonal islands whose location and spacing are determined by the underlying Au(111) zigzag reconstruction geometry. The islands are two atomic layers high and grow laterally with increasing coverage. A model for the nucleation and growth is proposed and a comparison with the growth of other metals on gold is given. We also qualitatively relate our structural results to published magnetic measurements.

Journal ArticleDOI
TL;DR: In this article, a new MBE growth method was proposed for InSb microcrystals on CdTe which has a nearly equal lattice constant to inSb. This method is based on the Sb incorporation into In droplets and thought to be useful for fabricating quantum well boxes.

Journal ArticleDOI
TL;DR: In this paper, optical and electrical measurements reveal uniform films over the thickness range 200-1000 A. They obtain optical absorption coefficients having values between those of Si and Ge and a relative permittivity having a value close to that of amorphous SiO2.
Abstract: Thermal sublimation of pure C60 and C70 has been used for depositing well‐characterized fullerene films on a variety of substrates. Film purity is determined by infrared absorption spectra and the extent of crystallinity of the face‐centered cubic structure by x rays. Thickness‐dependent optical and electrical measurements reveal uniform films over the thickness range 200–1000 A. We obtain optical absorption coefficients having values between those of Si and Ge and a relative permittivity having a value close to that of amorphous SiO2.

Journal ArticleDOI
TL;DR: In this article, the capacity of lH-benzotriazole (1H-BTA) to provide a protective and stable surface film able to withstand harsh chemical and thermal environments was studied.
Abstract: The utility of copper interconnects may ultimately depend on the ability to protect copper from corrosion. We have studied the capacity of lH-benzotriazole (1H-BTA) to provide a protective and stable surface film able to withstand harsh chemical and thermal environments. The film was characterized with electrochemical techniques, in situ ellipsometry, ex situ time-of-flight static secondary ion mass spectrometry, high-temperature mass spectrometry, and accelerated temperature and humidity tests. Several important passivating film properties (thickness, degree of polymerization, thermal stability, corrosion resistance) depend critically on the details of the film preparation conditions. The best corrosion protection is offered by the thin film formed on an oxidized Cu surface. This film has also shown the slowest growth kinetics and the highest degree of polymerization in the Cu-BTA structure. With more aggressive performance requirements for multilevel interconnections, higher conductivity metals, such as copper, are finding their way into a number of products. Copper is a relatively noble metal. Nevertheless, it reacts easily in ordinary, oxygen containing, environments (1). In view of the limited passivation offered by Cu-oxides, we have studied the effectiveness of organic azoles, such as lH-benzotriazole (1H-BTA), as a general method of controlling Cu degradation. For over 40 years 1H-BTA has been successfully used in the prevention of atmospheric Cu corrosion (2), in packaging, storage and transport, in the reduction of thermal oxidation and, in particular, in the protection of copper under immersed conditions (Ref. (3) and references within). The relevant literature is abundant but not unified in its teaching about bonding, thickness, composition and structure of the resulting film and the nature of its protection. Recent work from our laboratory, based on a combination of electrochemical, ellipsometric, and XPS data, has shown that the spontaneous reaction of Cu and 1H-BTA under a variety of conditions leads to the formation of Cu-BTA (4, 5), with copper being Cu +1 , as reported elsewhere (6-12). The formation of a Cu-N bond was clearly identified from the Cu LMM Auger lines. The film was formed both on an oxidized and an oxide-free Cu surface, in contrast to reports suggesting that the presence of Cu2O is a prerequisite for the buildup of CuBTA (8, 14). The thickness of the film was determined to be 0.5-4 nm in the pH range from 3 to 12, reaching 25 nm only under harsh conditions, i.e., in pH 2. Several recent studies of ultrahigh vacuum deposited 1H-BTA have indeed detected 1H-BTA adsorption on clean Cu metal (14-16). An electrochemical equivalent of such a film was formed in our laboratory at Cu 0 kept in

Journal ArticleDOI
TL;DR: In this article, the grain boundary junctions in YBa2Cu3O7 thin films were constructed by controlling the inplane epitaxy of the deposited film using seed and buffer layers.
Abstract: We have developed a new way of making grain boundary junctions in YBa2Cu3O7 thin films by controlling the in‐plane epitaxy of the deposited film using seed and buffer layers. We produce 45° grain boundaries along photolithographically defined lines. The typical value of the critical current density of the junctions is 103–104 A/cm2 at 4.2 K and 102–103 A/cm2 at 77 K, while the rest of the film has a critical current density of 1–3×106 A/cm2 at 77 K. The current‐voltage characteristics of the junctions show resistively shunted junction behavior and we have used them to fabricate dc superconducting quantum interference devices (SQUIDs) which show modulation at temperatures well above 77 K. This is the first planar high Tc Josephson junction technology that appears readily extendable to high Tc integrated circuits.

Patent
13 Feb 1991
TL;DR: In this paper, a polyimide substrate and a glass carrier plate are attached to a metal conductor, and an insulation layer covers the metal conductor and, in one embodiment, is made of polyimides having a cure temperature lower than the temperature at which interdiffusion occurs in the metal layers in the conductor.
Abstract: A biocompatible thin film electrical component is configured for use in a human body or other ionic liquid environment. A polyimide substrate is bonded to a glass carrier plate sized for handling by automatic equipment and a multiple-layer metal conductor is deposited on the substrate and patterned to define an electrical circuit or biosensor. The polyimide and the glass establish a bond therebetween that withstands handling yet is broken using biocompatible releasing agents and techniques. The polyimide substrate and glass carrier plate preferably have similar thermal expansion properties to reduce the likelihood of fracture and delamination problems during release of the substrate from the carrier plate. An insulation layer covers the metal conductor and, in one embodiment, is made of a polyimide having a cure temperature lower than the temperature at which interdiffusion occurs in the metal layers in the conductor.


Journal ArticleDOI
TL;DR: In this article, the bulk properties of cubic GaN/GaAs were investigated by cathodoluminescence, which revealed a broad midgap peak as well as several sharp emission peaks just below the expected band gap.
Abstract: We present the first comprehensive investigation of the bulk properties, both optical and structural, of cubic GaN as grown by plasma‐assisted molecular‐beam epitaxy on vicinal (100) GaAs substrates. X‐ray measurements determined the crystal structure of GaN/GaAs to be cubic with a lattice constant of 4.5 A. High resolution transmission electron microscopy revealed a high density of planar defects propagating along the GaN {111} planes. The majority of the defects originated from disordered regions at the GaN/GaAs interface. The optical properties of the films were investigated by cathodoluminescence which revealed a broad midgap peak as well as several sharp emission peaks just below the expected band gap. The data imply that the room temperature band gap of cubic GaN is approximately 3.45 eV.

Journal ArticleDOI
TL;DR: In this article, a superconducting epitaxial YBa2Cu3O7−δ/BaTiO3 thin film was grown on Si(001) by pulsed laser deposition.
Abstract: Epitaxial MgO thin films were grown on Si(001) by pulsed laser deposition. In spite of a large (−22.5%) lattice mismatch, epitaxy occurs with alignment of all crystallographic axes. Epitaxial quality and deposition rate are both sensitive to temperature and oxygen pressure. We believe this is the first demonstration of epitaxial MgO on Si. We employ MgO intermediate layers for superconducting epitaxial YBa2Cu3O7−δ/BaTiO3 thin films on Si with a critical current density of 6.7×105 A/cm2 at 77 K.

Journal ArticleDOI
TL;DR: In this paper, a composite membrane consisting of a thin palladium film supported on the outer surface of a porous glass cylinder was shown to be highly permeable to hydrogen, having an extremely high selectivity for hydrogen separation.

Journal ArticleDOI
TL;DR: In this paper, the effect of ambient oxygen pressure on the synthesis of epitaxial YBa2Cu3O7−x films on (100) SrTiO3 substrates by post-deposition annealing of amorphous precursor films was studied for oxygen partial pressures pO2 between 1.0 and 8.0×10−5 atm.
Abstract: The effect of ambient oxygen pressure on the synthesis of epitaxial YBa2Cu3O7−x films on (100) SrTiO3 substrates by post‐deposition annealing of amorphous precursor films was studied for oxygen partial pressures pO2 between 1.0 and 8.0×10−5 atm and annealing temperatures between 890 and 650 °C. A pO2−1/T diagram containing recent literature data regarding YBa2Cu3O7−x oxygen stoichiometry, phase stability, and liquid‐phase formation was compiled to provide guidance for the selection and interpretation of annealing conditions. The results evidence a strong dependency of growth properties on the oxygen pressure with enhanced c‐oriented epitaxy at lower pO2 values. A particularly interesting result is the formation of predominantly c‐oriented films at 740 °C and pO2=2.6×10−4 atm (0.2 Torr). Similar to YBa2Cu3O7−x films produced by in situ laser ablation at the same temperature and oxygen pressure, the films exhibited low ion channeling yields (χmin<0.1) and a dense (smooth) surface morphology, while critical ...

Journal ArticleDOI
TL;DR: The optical properties of vanadium oxide coatings are reviewed and the dependence of film properties on sample preparation and resultant film microstructure is stressed.
Abstract: Several oxides of vanadium undergo a transition from a semiconductor or insulating state to a metal phase at a critical temperature. Vanadium dioxide undergoes this transition near 68 degrees C, while V(2)O(5) undergoes a similar phase transition near 257 degrees C. During the transition a change in oxide crystal structure is accompanied by large changes in electrical and optical behavior. Thin films of vanadium oxides are capable of reversibly switching from the semiconductor to the metallic state at high speeds and with high spatial resolution. Therefore, these oxides have potential use, particularly in thin film form, for a wide variety of applications involving thermally activated electronic or optical switching devices. Such films are of considerable technical interest because of applications in chemical sensors, energy-conserving coatings, transparent conductors, and switching materials. The numerous potential electronic, optical, and optoelectronic device applications which have been suggested have stimulated work on the preparation of thin films by a variety of techniques, including chemical vapor deposition, solgel, evaporation, and sputter deposition. This paper reviews the optical properties of vanadium oxide coatings and stresses the dependence of film properties on sample preparation and resultant film microstructure.

Journal ArticleDOI
TL;DR: In this paper, it was found that the crystal orientation and grain structure change with B2H6 flow rate and the decreasing of the film transmittance due to the free carrier absorption in the wavelength region above 1000 nm was observed and it seems that the impurity scattering was the dominant interaction during this process.
Abstract: The highly conductive and textured ZnO films have been grown by metalorganic chemical vapor deposition using diethylzinc and H2O as reactant gases. The B2H6 gas has also been successfully used as an n‐type dopant gas to obtain highly conductive ZnO with a sheet resistivity for 2‐μm‐thick film as low as 10 Ω/⧠ at the very low temperature of 150 °C. It was found that the crystal orientation and grain structure change with B2H6 flow rate. The decreasing of the film transmittance due to the free‐carrier absorption in the wavelength region above 1000 nm was observed and it seems that the impurity scattering was the dominant interaction during this process. The shift of the absorption edge due to band filling was also observed as the B2H6 flow rate was increased.

Journal ArticleDOI
TL;DR: In this article, a model for the condensation of energetic carbon atoms into diamond-like films in which a quench-type surface accommodation mechanism is operative is proposed, and the degree of diamondlike film character is found to depend upon the deposition technique as well as the substrate temperature and thermal diffusivity.
Abstract: Trends in recently reported data on high sp3 fraction (up to 85%), nonhydrogenated amorphous diamond‐like carbon films deposited by ion beam sputtering and laser vaporization are examined. The degree of diamondlike film character is found to depend upon the deposition technique as well as the substrate temperature and thermal diffusivity. The data suggest that the combination of incident particle kinetic energy and surface accommodation determine the physical properties of the resultant film. A model is proposed for the condensation of energetic carbon atoms into diamondlike films in which a quench‐type surface accommodation mechanism is operative.

Journal ArticleDOI
TL;DR: In this paper, the authors studied the oxidation kinetics of copper thin films at temperatures below 200 °C in air and found that the amorphous Cu65Ti35 alloy film is more oxidation resistant than the crystalline phase.
Abstract: The oxidation kinetics of copper thin films have been studied at temperatures below 200 °C in air. The protection of copper from oxidation can be achieved by alloying copper film with Ti, Pd, Cr, or Al. The influence of the composition and microstructure to the oxidation rate has been studied. The compounds Cu3Ti, Cu3Pd, and CuAl2 are stable in the oxidation ambient. The formation of Cr‐oxide, which is a passive oxide, explains the inhibition of oxidation on Cu‐Cr films. Compared with the crystalline phase, the amorphous Cu65Ti35 alloy film is more oxidation resistant. A TiN layer with oxygen incorporated is more effective in preventing copper oxidation than a TiN layer without oxygen incorporated. A passivating Si3N4 layer on copper thin films can prevent copper oxidation effectively at 350 °C in oxygen ambient.

Journal ArticleDOI
TL;DR: In this paper, the authors investigated the tensile and compressive total (thermal and intrinsic) stress in diamond films prepared by microwave plasma CVD, as a function of methane concentration (0.2% −3.0%) and deposition temperature (600-900°C).
Abstract: The stress in diamond films prepared by microwave plasma CVD was investigated as a function of methane concentration (0.2%–3.0%) and deposition temperature (600–900 °C). Tensile and compressive total (thermal and intrinsic) stress were observed, depending on the deposition conditions. The thermal stress is compressive and relatively constant (0.215–0.275 GPa) over the temperature range investigated. The intrinsic stress is tensile and its origin is interpreted in terms of the grain boundary relaxation model. Calculations indicate a value of 0.84 GPa, using the grain boundary model, which is in fair agreement with the measured value. For the methane series, the tensile intrinsic stress decreases with increasing the methane fraction. The increasing compressive stress is ascribed to increased impurity (hydrogen and nondiamond phase carbon) incorporation with increasing methane fraction. 15N nuclear reaction analysis shows a linear correlation between hydrogen in the film and methane in the supply gas while spectroscopic ellipsometry shows a direct correlation between optically absorbing nondiamond (sp2) carbon incorporation and methane. For the temperature series, the intrinsic tensile stress increases with deposition temperature. The increase is ascribed to decreasing sp2 C incorporation with temperature, as confirmed by spectroscopic ellipsometry measurements.

Journal ArticleDOI
TL;DR: In this article, the dependence of a near-band edge emission on the indium mole fraction of InGaN has been investigated, and the photoluminescence has been observed for the first time.
Abstract: InGaN single‐crystal films were grown on (0001) plane sapphire substrates at 800 °C by metalorganic vapor phase epitaxy. By using such a high temperature for growth, the crystalline quality has been greatly improved. But a high nitrogen over pressure and high indium source flow rate were necessary to achieve significant indium incorporation during growth. For the first time, photoluminescence has been observed in InGaN, and near‐band edge emission is seen in the photoluminescence at 77 K. From this photoluminescence, the dependence of a near‐band edge emission on the indium mole fraction of InGaN has been investigated.