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1.
In this study, we discuss the case for integration of epitaxial (Pb,La)(Zr,Ti)O3 (PLZT) thin films with silicon for electro-optic device applications. PLZT films, approximately 500 nm thick, were grown by on-axis radio frequency magnetron sputtering on CeO2/YSZ-buffered Si(100) substrate with a SrRuO3 electrode layer embedded between CeO2 and PLZT. The structural properties and surface topography of the different oxide layers were examined with X-ray diffraction analysis and atomic force microscopy. The perovskite thin films were predominantly (001)-oriented, with a (002) rocking curve halfwidth of approximately 0.3° and a surface roughness compatible with requirements for application in optical devices. The PLZT cation stoichiometry was assessed from quantitative X-ray photoelectron spectroscopy. These measurements uncovered a substantial depletion of lead in the film surface for layers deposited at substrate temperatures above ~ 600 °C, whereas the surface concentration of La, Zr and Ti remained virtually unaffected over a wide range of growth temperatures. 相似文献
2.
3.
Using pulsed magnetron sputtering at low substrate temperature (Ts = 580 °C) the homoepitaxial growth on Si(111) was studied. The films were comprehensively characterized by cross-section transmission electron microscopy and various diffraction methods. Up to a film thickness of 1240 nm no breakdown of the epitaxial growth was observed. The surface microstructure, characterized by electron backscatter diffraction, exhibits exclusively crystalline structure with (111) orientation. Careful analysis of selected area electron diffraction patterns and high-resolution X-ray diffraction data clearly proves the existence of twinning/stacking faults in the {111} planes. Besides these defects – which are typical for low-temperature epitaxy – no additional significant defects related to the energetic particle bombardment by the sputter deposition method are observed. 相似文献
4.
The epitaxial growth of gallium nitride thin film was obtained on the inclined Si(111) substrates by the process of ion-beam-assisted evaporation (IBAE) at the low temperature of 500 °C. The film composition determined by Rutherford backscattering spectrometry shows that the synthesized film is a stoichiometric nitride. The epitaxial quality of GaN film is enhanced by minimizing the bombardment-induced film damage by decreasing the ion flux. However, the crystallinity of the GaN film becomes very poor when the ion flux is not sufficient to densify the film. The optimum flux ratio of N+2 to Ga and the energy of incident N+2 ions for the epitaxial growth were found to be 3.4 and 50 eV, respectively. The GaN film deposited on the 4 °-inclined Si (111) with respect to substrate surface shows much better crystalline quality compared with that on the 0 ° inclined Si(111) due to many stable nucleation sites. A thin amorphous layer exists at the interface between GaN and Si(111) substrate and acts as a buffer zone enabling the subsequent epitaxial growth of GaN by relaxing the large misfit strain (23%) in the early stage of film growth. The epitaxial GaN film shows an orientational relation with the Si(111) substrate. 相似文献
5.
A. ZianiC. Le Paven-Thivet D. FasquelleL. Le Gendre R. Benzerga F. TessierF. Cheviré J.C. CarruA. Sharaiha 《Thin solid films》2012,520(14):4536-4540
LaTiOxNy thin films have been deposited by RF sputtering on (001) Nb-doped SrTiO3 and (001) MgO single-crystalline substrates at high temperature (TS = 800 °C) under different nitrogen ratios in the plasma (vol.% N2 = 0, 25, 71). The band gaps ranged from Eg = 3.30 eV for the epitaxial transparent film containing no nitrogen to Eg = 2.65 eV for the textured coloured film containing a moderate amount of nitrogen. Dielectric characterization in the frequency range [100 Hz-1 MHz], using a metal-insulator-metal structure, has shown a stable permittivity and loss tangent of the epitaxial low-nitrided LaTiOxNy film with values of ε′ = 135 and tanδ = 1.2 10− 2 at 100 kHz (RT). 相似文献
6.
Koichiro Okamoto Shigeru Inoue Takayuki Nakano Tae-Won Kim Masaharu Oshima Hiroshi Fujioka 《Thin solid films》2008,516(15):4809-4812
We have grown AlN films on single-crystalline Mo(110), (100), and (111) substrates using a low temperature pulsed laser deposition (PLD) growth technique and investigated their structural properties. Although c-axis oriented AlN films grow on Mo(100), the films contain 30° rotated domains due to the difference in the rotational symmetry between AlN(0001) and Mo(100). AlN films with only poor crystalline quality grow on Mo(111) substrates, probably due to the poor surface morphology and high reactivity of the substrates. On the other hand, single crystal AlN films grow epitaxially on Mo(110) substrates with an in-plane relationship of AlN[11-20] // Mo[001]. Reflection high-energy electron diffraction or electron backscattered diffraction analysis has revealed that neither in-plane 30° rotated domains nor cubic phase domains exist in the AlN films. X-ray reflectivity measurements have revealed that the heterointerface between AlN and Mo prepared by PLD at 450 °C is quite abrupt. These results indicate that PLD epitaxial growth of AlN on single crystal Mo substrates is quite promising for the fabrication of future high frequency filter devices. 相似文献
7.
Yasunobu Akiyama Katsuya Shitanaka Young-Sik Shin Nobuyuki Imaishi 《Thin solid films》2007,515(12):4975-4979
Lithium niobate films grown epitaxially on sapphire substrate were prepared using a thermal chemical vapor deposition method from the metalorganic compounds Li(C11H19O2) and Nb(OC2H5)5. The range of operating conditions for obtaining pure epitaxially grown LiNbO3 without other oxides is within that for obtaining pure polycrystalline LiNbO3 grown on silicon substrate. On analyzing the composition of the epitaxially grown LiNbO3 film, the composition of the film was similar to that of the LiNbO3 solid solution in the phase diagram of the Li-Nb composite oxide obtained for crystal growth from a molten solution. 相似文献
8.
The growth of TiO2 films in the anatase crystal structure was investigated using reactive sputter deposition with H2O serving as the oxidizing species. With water vapor, the formation of phase-pure anatase TiO2 thin films via epitaxial stabilization on (001) LaAlO3 was achieved, although crystallinity was slightly inferior to that obtained when O2 was employed. Films grown using water vapor exhibited a rougher surface morphology indicating a difference in growth mechanisms. At low H2O pressure, the formation of a TinO2n−1 Magnéli phase was observed. When hydrogen was employed during growth, mixed phase films of rutile and anatase resulted. The development of crystallinity and phase as a function of deposition temperature and oxidant pressure are discussed. 相似文献
9.
N.S.L.S. Vasconcelos J.S. Vasconcelos V. BouquetS.M. Zanetti E.R. LeiteE. Longo L.E.B. SoledadeF.M. Pontes M. Guilloux-ViryA. Perrin M.I. BernardiJ.A. Varela 《Thin solid films》2003,436(2):213-219
Oriented LiNbO3 thin films were prepared using a polymeric precursor solution deposited on (0001) sapphire substrate by spin coating and crystallized in a microwave oven. Crystallization of the films was carried out in a domestic microwave oven. The influence of this type of heat treatment on the film orientation was analyzed by X-ray diffraction and electron channeling patterns, which revealed epitaxial growth of films crystallized at 550 and 650 °C for 10 min. A microstructural study indicated that the films treated at temperatures below 600 °C were homogeneous and dense, and the optical properties confirmed the good quality of these films. 相似文献
10.
Peter Sigmund 《Thin solid films》2012,520(19):6031-6049
The paper is an attempt to trace milestones in the understanding of sputtering by ion bombardment. The field developed rapidly between 1955 and the end of the 1980s, but several important aspects are still under active investigation today. The focus here is on the evolution of the present understanding of the process of sputter emission. The presentation is based primarily on physical arguments, supported by results from theory referred to in the text. Many research groups have contributed to this field. Doing justice to them all appears close to impossible within the given frame. 相似文献
11.
The growth of epitaxial MgO/TiN multilayer films on (001) Cu has been investigated. In particular, epitaxial structures were grown on (001) Cu layers that were epitaxial on (001) SrTiO3. X-ray diffraction and reflection high-energy electron diffraction indicate that the multilayer structures are epitaxial on the (001) Cu surface. The motivation is the use of crystalline MgO/TiN multilayers as a diffusion barrier to both copper and oxygen. MgO/TiN multilayers are potentially useful as diffusion barriers for Cu interconnects on semiconductors as well as for superconducting wires based on the epitaxial growth of cuprate superconductors on biaxially textured copper. 相似文献
12.
We report the effect of growth temperature and annealing on microstructural, elemental and emission properties of as-grown and in-situ annealed MgZnO thin films, containing ∼ 10 at. % Mg, grown at high temperature by RF sputtering. Microstructural analysis carried out by TEM reveals formation of thin oxide layer with increased layer thickness on growth temperature, in the interface between Si substrate and MgZnO thin film. Irrespective of growth temperature, increase in Mg mole fraction with increase in thickness of MgZnO thin film is observed from EDX and AES spectroscopy, and a maximum of 14 at. % Mg is observed at 800 °C. The photoluminescence investigation shows blue shift of 104 meV in MgZnO film grown at 800 °C, compared to the film grown at 600 °C, which is due to the enhancement of the Mg incorporation at higher temperature. In addition, annealing at the growth temperature enhanced the intensity ratio of the UV/deep level emission and increased the grain size. Thermal treatment in a vacuum improved the emission efficiency and changed the origin of the point defects. 相似文献
13.
We report on epitaxial growth of ZnO on (112) orientated CuInS2 thin films. Step-by-step growth and investigation by photoelectron spectroscopy (PES) and low energy electron diffraction (LEED) provided information on the growth mode and the electronic structure of the ZnO-CuInS2-interface. During the initial growth no ZnO is deposited. Instead a monolayer of ZnS is formed by depletion the CuInS2 surface of excess sulfur. Thereafter, the ZnO growth starts on the ZnS buffer layer. The band alignment derived from PES shows that the ZnS buffer layer is thin enough to provide a beneficial band alignment for photovoltaic applications. 相似文献
14.
We studied the growth and electrical properties of single crystalline mixed (Nd1 − xGdx)2O3 (NGO) thin films and compared the results with those of the binary Gd2O3 and Nd2O3 thin films, respectively. Epitaxial ternary NGO thin films were grown on Si(100) substrates using modified solid state molecular beam epitaxy. The films were characterized physically using various techniques. The capacitance equivalent oxide thickness of a 4.5 nm NGO thin film extracted from capacitance-voltage (C-V) characteristics was 0.9 nm, which is lower than all values reported earlier for other crystalline oxides. The leakage current density and the density of interface traps were 0.3 mA/cm2 at |Vg − VFB| = 1 V and 1.4 × 1012/cm2, respectively. These excellent electrical properties of NGO thin films demonstrate that such ternary oxides could be one of the promising candidates for gate dielectrics in the upcoming generations of complementary metal oxide semiconductor (CMOS) devices. 相似文献
15.
An overlay coating material was deposited on a single crystal superalloy SRR99 by laser cladding.The microstructure and oxidation behavior of this coating was investigated through scanning electron microscopy(SEM) and X-ray diffraction(XRD). The results indicated that although the composition of the coating was chosen based on the γ' composition in René N5 superalloy, the primary solidification phase of this coating during laser cladding was γ-Ni. Furthermore, under the laser cladding condition, fine parallel dendrites grew epitaxially in the coating from the substrate, indicating the single crystal structure of the substrate was reproduced. When the single crystal MCrAlY coating was oxidized at 1000?, both Al_2O_3 and Al_2O_3 formed during initial oxidation process. As the oxidation time proceeded, the presence of Al_2O_3 facilitated the formation of NiAl_2O_4 spinel oxide. Once the spinel was observed, it flourished and induced some porosity in the scale. When the scale thickness increased to 6–7 μm, large area spallation of the scale began. 相似文献
16.
《Vacuum》2004,75(3):207-215
Radio frequency magnetron sputtering of polypropylene (PP) using argon as a working gas was applied in order to prepare organic films. Changes of the structure and morphology of the PP target and sputtered films have been investigated by infrared spectroscopy, AFM and scanning electron microscopy. It has been shown that the sputtered films are hydrocarbon plasma polymers. The increased incorporation of OH groups into the deposited films was found as a consequence of the PP target history. 相似文献
17.
Epitaxial SrTiO3 (STO) films have been grown on TiN buffered Si(001) by pulsed laser deposition. The TiN layer was in situ deposited at 540, 640 or 720°C whereas the STO film was grown at a fixed temperature of 640°C. We have studied the effect of the growth temperature of TiN on the epitaxial relationship of STO/TiN heterostructures. It is found that for TiN grown at 540 or 640°C the epitaxial relationship is 001STO 001TiN, and for TiN grown at 720°C it changes to (101)STO (001)TiN and [
01]STO [1
0]TiN (or [
01]STO [110]TiN). This change of relationship is accompanied by a sharp reduction in the out-of-plane lattice constant of the TiN layer. Fourier transform infrared spectra show that the longitudinal optic modes are active for all the STO films, but the absorption peak associated with the transverse optic mode is observed only in the (101) oriented STO films. 相似文献
18.
The epitaxial growth of β-FeSi2 films produced on flat and patterned Si(001) substrates under various substrate temperatures (Ts) with deposition rates of Fe (VFe) was investigated by transmission electron microscopy (TEM). In the film deposited on the flat Si(001) substrate, precipitates of flat-bottom shaped β-FeSi2 and those of round-bottom shaped α-FeSi2 were formed at Ts = 500 °C and VFe = 0.02 nm/s. The β-FeSi2 adopted the epitaxy to (001)Si plane, while α-FeSi2 selected the epitaxy to {111}Si planes inside the Si matrix. At Ts = 350 °C and VFe = 0.01 nm/s, a continuous β-FeSi2 layer were formed epitaxially on the Si(001) substrate without forming α-FeSi2. It was found that the lower temperature and the higher Fe-concentration suppress the formation of α-FeSi2 and promote the formation of β-FeSi2. In addition, the morphology of β-FeSi2 changed from fine isolated precipitates (islands) to a continuous layer with increasing the deposition rate and the substrate temperature. In the film deposited on the patterned Si(001) substrate at Ts = 500 °C and VFe = 0.02 nm/s, on the other hand, both β- and α-FeSi2 precipitates were formed on the top-hills and the valleys of the patterned substrate, while only α-FeSi2 precipitates were formed on the sidewalls. These results demonstrate that not only the growth conditions but also geometric situations affect strongly the epitaxial growth of FeSi2 precipitates. 相似文献
19.
Epitaxial Si-based tunnel diodes 总被引:1,自引:0,他引:1
P.E Thompson K.D Hobart M.E Twigg S.L Rommel N Jin P.R Berger R Lake A.C Seabaugh P.H Chi D.S Simons 《Thin solid films》2000,380(1-2):145-150
Tunneling devices in combination with transistors offer a way to extend the performance of existing technologies by increasing circuit speed and decreasing static power dissipation. We have investigated Si-based tunnel diodes grown using molecular beam epitaxy (MBE). The basic structure is a p+ layer formed by B delta doping, an undoped spacer layer, and an n+ layer formed by Sb delta doping. In the n-on-p configuration, low temperature epitaxy (300–370°C) was used to minimize the effect of dopant segregation and diffusion. In the p-on-n configuration, a combination of growth temperatures from 320 to 550°C was used to exploit the Sb segregation to obtain a low Sb concentration in the B-doped layer. Post-growth rapid thermal anneals for 1 min in the temperature interval between 600 and 825°C were required to optimize the device characteristics. Jp, the peak current density, and the peak-to-valley current ratio (PVCR), were measured at room temperature. An n-on-p diode having a spacer layer composed of 4 nm Si0.6Ge0.4, bounded on either side by 1 nm Si, had a Jp=2.3 kA/cm2 and PVCR=2.05. A p-on-n tunnel diode with an 8 nm Si spacer (5 nm grown at 320°C, 3 nm grown at 550°C) had a Jp=2.6 kA/cm2 and PVCR=1.7. 相似文献
20.
Fumikazu Imai Kimio Kunimori Takaaki Manabe Toshiya Kumagai Hisakazu Nozoye 《Thin solid films》1997,310(1-2):184-193
We synthesized titanium oxide thin films on MgO(100) single-crystal substrates by two reactive deposition methods and compared the structures of the thin films formed by these methods. In one method (pulsed-molecular-beam deposition method), molecular oxygen is supplied to the substrates by using a pulsed-molecular-oxygen beam source and deposition of one unit layer of titanium and subsequent supply of molecular oxygen are repeatedly performed. In the other method (radical beam deposition method), atomic oxygen is irradiated to the substrates by using an atomic oxygen beam generated by the radical beam source and irradiation of the atomic oxygen and deposition of titanium are simultaneously performed. In the case of the pulsed-molecular-beam deposition method, the crystal structure was changed by increasing the number of oxygen pulses supplied from the beam source. We found that the crystal structure of titanium oxide depended on the composition ratio of O:Ti in the film. The maximum ratio of O:Ti attainable by this method was 1.85, and at this ratio, (100)-oriented pseudorutile was formed. In the case of the radical beam deposition method, (100)-oriented anatase was formed below the titanium deposition rate of 0.10 nm/s and pseudorutile (TiO2−δ) was formed above 0.15 nm/s. The pseudorutile structure synthesized on this experiment was very stable in air. We concluded that the crystal structure of the pseudorutile is a new crystal structure of titanium oxide. 相似文献