Showing papers on "Sputtering published in 1980"
IBM1
TL;DR: In this paper, it was shown that mass correlations are quite unsuccessful, whereas most observations can be understood rather well in terms of bonding, and that the cascade component of sputtering, normally judged to be predominant, should give significantly less compositional change than is observed.
269 citations
TL;DR: In this article, a detailed study of these films has been carried out using x-ray diffraction, scanning electron microscopy, reflection electron diffraction and optical measurement, and electromechanical measurement.
Abstract: ZnO films with an excellent crystal orientation and surface flatness have been prepared by high‐deposition‐rate rf planar‐magnetron sputtering. A detailed study of these films has been carried out using x‐ray diffraction, scanning electron microscopy, reflection electron diffraction, optical measurement, and electromechanical measurement. These films have the c‐axis perpendicular to the substrate. The value of the standard deviation angle σ of the c‐axis orientation distribution is smaller than 0.5°, and the minimum value of σ is 0.35°, where the sputtering conditions are that the gas pressure is 5×10−3–3×10−2 Torr of premixed Ar (50%)+O2(50%) and the substrate temperature is 300–350 °C. ZnO films with a thickness up to 48 μm have been reproducibly prepared without the decreases of film quality and surface flatness. The surface flatness of these films is similar to that of a glass substrate. An optical waveguide loss for the TE0 mode of the He‐Ne 6328‐A line is as low as 2.0 dB/cm in a 4.2‐μm‐thick film, ...
257 citations
TL;DR: In this paper, a normalized energy function and two parameters for each ion target combination are characterized, one of these parameters is the threshold energy and the other parameter is a multiplication factor, which depend mainly on the ion and target mass M1 and M2 and on the surface binding energy EB.
Abstract: Sputtering yields for different ions and materials at low ion energies have a similar energy dependence. Due to this similarity, yield data can be characterized by a normalized energy function and two parameters for each ion target combination. One of these parameters is the threshold energy. An energy scaling can be based on this parameter. The other parameter is a multiplication factor. Both parameters depend mainly on the ion and target mass M1 and M2 and on the surface binding energy EB. An analytic expression for the normalized functions and both the parameters is given. This empirical relation also allows an estimate of unknown sputtering data, if M1, M2, and EB are noted. A physical interpretation of the empirical relation is given for the case M1≪M2, as in this case special collision processes which dominate the sputtering can be identified.
234 citations
TL;DR: In this paper, surface acoustic wave properties, including phase velocity, a coupling coefficient, a propagation loss, and a temperature coefficient of delay, were measured for SAW propagating along the c-axis of the ZnO films, on the (0112) planes of sapphire.
Abstract: Single‐crystal films of ZnO have been epitaxially grown on the (0001) and (0112) planes of sapphire by rf sputtering. Crystalline structures and electrical properties of the films were investigated. Surface acoustic wave (SAW) properties, including a phase velocity, a coupling coefficient, a propagation loss, and a temperature coefficient of delay, were measured for SAW propagating along the c‐axis of the ZnO films, on the (0112) planes of sapphire. Availability of this structure for high‐frequency SAW devices has been demonstrated by a filter with a 1050‐MHz center frequency.
205 citations
TL;DR: In this article, the authors showed that the hillock formation observed in the present case has been explained on the basis of thermal stress relaxation occuring by diffusion creep, with the additional effect of the high surface diffusion of silver atoms on an oxygen-covered silver surface.
187 citations
TL;DR: In this paper, a multilayer model was formulated, its most conspicuous feature being a sheath near to the Al interface comprised of metallic Ni particles in an Al2O3 matrix.
Abstract: Spectrally selective surfaces on Al metal sheets were prepared by dc anodization in dilute phosphoric acid followed by black coloration via ac electrolysis in a bath containing NiSO4. These coatings had good durability, as found from several accelerated tests. The optical performance was studied by the recording of hemispherical reflectance or specular reflectance in conjunction with diffuse light scattering. From these results we extracted a solar absorptance of 0.93–0.96 and a corresponding thermal emittance of 0.10–0.20. The structure of the coatings was investigated by scanning electron microscopy on fractured specimens, Auger electron spectroscopy combined with depth profiling by sputtering, and atomic absorption analysis. Based on this information, a multilayer model was formulated, its most conspicuous feature being a sheath near to the Al interface comprised of metallic Ni particles in an Al2O3 matrix. The optical properties of this layer were described either by the Maxwell Garnett theory or the ...
177 citations
TL;DR: In this paper, it was shown that films with low resistivity (∼4×10−4 Ω cm) and high optical transmission (≳85% between 4000 and 8000 A) can be prepared on low-temperature (40−180 °C) substrates with O2 partial pressures of (2 −7)×10 −5 Torr.
Abstract: High‐quality 800‐A‐thick films of tin‐doped indium oxide have been prepared by magnetron sputtering. It is shown that films with low resistivity (∼4×10−4 Ω cm) and high optical transmission (≳85% between 4000 and 8000 A) can be prepared on low‐temperature (40–180 °C) substrates with O2 partial pressures of (2–7)×10−5 Torr.
172 citations
TL;DR: In this paper, a new type of cathode sputtering apparatus with two targets facing each other was developed to prepare magnetic films at a high deposition rate without the extreme rise of the substrate temperature.
Abstract: A new type of cathode sputtering apparatus with two targets facing each other has been developed to prepare magnetic films at a high deposition rate without the extreme rise of the substrate temperature. When two disks of iron and nickel were used as targets, the maximum deposition rates obtained were approximately 4000 and 5000 A/min, respectively. The substrate temperature was not elevated above 200°C during sputtering. The high rate deposition of Mo permalloy films also was attempted by co-sputtering of two facing targets composed of disks of iron and nickel and chips of molybdenum. The Vicker's hardness of the obtained Mo permalloy films was about 900 and the typical values of permeability at 1 MHz magnetic field and coercive force at dc magnetic field of them were about 2500 and 0.16 Oe, respectively.
159 citations
TL;DR: In this paper, a single-crystalline aluminum nitride film is grown on a basalplane sapphire substrate and the c-axis oriented films are grown on glass and gold-film substrates at substrate temperatures as low as from 50 to 500 °C by using reactive rf planar magnetron sputtering.
Abstract: A single‐crystalline aluminum nitride film is grown on a basal‐plane sapphire substrate and the c‐axis‐oriented films are grown on glass and gold‐film substrates at substrate temperatures as low as from 50 to 500 °C by using reactive rf planar magnetron sputtering. Surface acoustic waves are generated in both structures where interdigital transducers are located on the top of an aluminum nitride film and at the interface between the film and the substrate sapphire. The effective surface acoustic wave coupling factor k2 is 0.09 and 0.12%, respectively, for these interdigital transducer configurations. The aluminum nitride films sputtered on a gold film on a glass rod and on a glass sheet itself are also piezoelectric and used as bulk and surface acoustic wave transducers, respectively. These piezoelectric aluminum nitride films on glass and metal‐film substrates have become available for the first time because film growth at low temperature has become possible in the present study.
155 citations
TL;DR: In this paper, it was shown that the ion peening transition may be controlled by the transfer of momentum to the depositing film, which is consistent with results obtained in low-pressure, cylindrical post-magnetron sputtering.
Abstract: Bombardment of thermally evaporated chromium films with energetic inert gas ions during deposition (ion peening) causes marked changes in properties when the dose exceeds a minimum critical value. The property changes are characterized by a sharp reversal of intrinsic stress from high‐tensile to high‐compressive values, increases in the optical reflectance and optical density to levels approaching pure bulk chromium, and enhanced resistance to oxidation on heating. Observations of the shift in critical ion dose with accelerating voltage and ionic mass (argon and xenon) indicate that the ion peening transition may be controlled by the transfer of momentum to the depositing film. This observation is found to be consistent with results obtained in low‐pressure, cylindrical post‐magnetron sputtering, which ion peening was devised to simulate.
149 citations
TL;DR: In this article, a thermalized ion explosion model is proposed for high energy sputtering which is expected to describe track formation in dielectric materials, and the model is consistent with the observed total sputtering yield and the dependence of the yield on the primary ionization rate of the incident ion.
Abstract: A velocity spectrum of neutral sputtered particles as well as a low resolution mass spectrum of sputtered molecular ions was measured for 4.74 MeV F-19(+2) incident of UF4. The velocity spectrum is dramatically different from spectra taken with low energy (keV) bombarding ions, and is shown to be consistent with a hot plasma of atoms in thermal equilibrium inside the target. A thermalized ion explosion model is proposed for high energy sputtering which is expected to describe track formation in dielectric materials. The model is shown to be consistent with the observed total sputtering yield and the dependence of the yield on the primary ionization rate of the incident ion.
TL;DR: In this article, the temperature at which ZnO is deposited is found to be of crucial importance for the photovoltaic performance of the cells, and Maxima of the open-circuit voltage, the shortcircuit current, and the dark resistance are observed for deposition temperatures between 230 and 240°C.
TL;DR: In this article, an extension of the SAMPLE general process simulator to plasma etching and metallization is described, where the etching algorithm is divided into isotropic, anisotropic, and direct milling components.
Abstract: The extension of the general process simulator SAMPLE to plasma etching and metallization is described The etching algorithm is divided into isotropic, anisotropic, and direct milling components and is suitable for modeling wet etching, plasma etching, reactive ion etching, and ion milling Separate deposition algorithms are used for CVD, sputtering, and planetary deposition With the extension, it is possible to use a simple keyword repertoire to simulate a sequence of photolithography, etching, and deposition steps to obtain device cross sections at each stage of fabrication
TL;DR: In this article, the energy dependence of H2O ice erosion has been measured for Hydrogen and Helium ions between 6 keV and 1.8 MeV, and the erosion coefficient S (molecules removed per incident ion) is much too large to be explained by normal sputtering due to nuclear energy loss.
TL;DR: In this paper, the authors used X-ray photoelectron spectroscopy (XPS) and AES to characterize the air-exposed and sputter-cleaned surfaces of glow-discharge-produced Si1−xCx:H (x=0.05 to 0.90) films.
Abstract: X‐ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) were used to characterize the air‐exposed and sputter‐cleaned surfaces of glow‐discharge‐produced Si1−xCx:H (x=0.05 to 0.90) films. On the air‐exposed surfaces, silicon was preferentially oxidized with the enriched carbon existing as graphite or hydrocarbon. Signal intensities obtained from the surfaces sputter cleaned with 1 keV Ar+ ion beams indicated no significant preferential sputtering of C to Si for these films. The values of the carbon 1s and silicon 2p and 2s binding energies as well as the valence band spectra suggested a significant change in the local atomic configurations at x∼0.6–0.7. Based on these XPS and AES results and the reported IR absorption data, a slightly cross‐linked, carbon and hydrogen substituted polysilicon and an almost fully cross‐linked, silicon and hydrogen substituted polycarbon were proposed to describe the structure of films below and above x∼0.6–0.7, respectively.
TL;DR: In this article, a single metal (Mo) sputtered in a variety of gases (Ne, Ar, Kr, Xe) was found to have high compressive stress, maximum reflectance, minimum resistivity, entrapped inert gas, and dense Zone-T microstructure.
Abstract: Previous work by the present authors on metal films sputtered from cylindrical‐post magnetron sources has established the existence of an abrupt transition in internal stress and other properties that occurs as the working pressure is lowered. High compressive stress, maximum reflectance, minimum resistivity, entrapped inert gas, and dense, Zone‐T microstructure were found in a wide variety of pure metals and alloys when sputtered in argon at sufficiently low pressures. The present study reports this same phenomenon for a single metal (Mo) sputtered in a variety of gases (Ne, Ar, Kr, Xe). In this case the transition pressure varies inversely with the mass of the sputtering gas, from less than 0.3 Pa for xenon to over 0.9 Pa for neon. The concentration of inert gas in the films also varies inversely with the mass, increasing by two orders of magnitude from krypton to neon. Deposition through a narrow slit‐aperature established that the entrapped gas comes from the sputtering cathode (backscattered, neutral...
TL;DR: In this paper, the rf diode sputtering of a ZnO target using an Ar/O2 gas mixture was studied as a function of the O2 content of the sputtering gas.
Abstract: The rf diode sputtering of a ZnO target using an Ar/O2 gas mixture was studied as a function of the O2 content of the sputtering gas. Films sputtered using gas mixtures containing 0–100% O2 were investigated. Glow discharge spectrometry was used to monitor the ionized species present in the various Ar/O2 plasmas. The crystallographic orientation of the films was found to be highly correlated with the ratio of the number of Zn to ZnO ions in the plasma. The most highly ordered films were obtained when the Zn to ZnO ion ratio was at a minimum which occurred when a 75% Ar/25% O2 gas mixture was used. This result can be explained in terms of the relative degree of oxidation of the ZnO target surface and the number of secondary electrons in the plasma for the various Ar/O2 sputtering gas mixtures.
TL;DR: In this paper, a series of experiments for growing epitaxial PLZT thin films has been made with rf sputtering, and X-ray and electron diffraction analyses confirm that the fabricated films grow epitaxially on SrTiO3 and MgO crystals.
Abstract: A series of experiments for growing epitaxial PLZT thin films has been made with rf sputtering. X-ray and electron diffraction analyses confirm that the fabricated films grow epitaxially on SrTiO3 and MgO crystals. A good transparency in the region above 0.4 μm to infrared with good ferroelectric properties is obtained. Propagation loss of He−Ne laser light is less than 6 dB/cm, and the PLZT thin film is a promising candidate for the optical modulator and other functional elements for integrated optics.
TL;DR: In this article, single-phase CuInS 2 thin films were prepared by r.f. sputtering and the asdeposited films were p type with resistivities in the range 10 −1 −10 1 ω cm.
TL;DR: In this article, the authors studied the sputtering of UF-4 surfaces by ions with energies in the electronic stopping region and found that the observed sputtering yields are very large and are associated with the electronic starting power.
Abstract: We have studied the sputtering of ^(235)U from UF_4 surfaces by ions with energies in the electronic stopping region. The observed sputtering yields are very large and are associated with the electronic stopping power. Measured yields produced by ^(19)F ions at energies ranging from 1/16 MeV/amu to 1½ Mev/amu exhibit a peak of S = 7.1 ± 1.5 for ^(19)F^(+3) at an energy of ¼ MeV/amu. The data suggest that the yield depends on the charge state of the incident ion. The yields are independent of target temperature in the range between 70°C and 170°C. The energy spectrum of the neutral component of the sputtered particles produced by ¼ MeV/amu ^(19)F^(+2) has been measured with the mechanical time-of-flight spectrometer developed by Weller and Tombrello. The spectrometer data indicate that a large fraction of the sputtered particles is charged. We also describe the behavior of high energy sputtering of UF_4 by ^(4)He, ^(16)O and ^(20)Ne. Experiments with ^(16)O and ^(20)Ne beams at 100 keV show that the Sigmund theory adequately describes the sputtering of UF_4 in the nuclear stopping region.
TL;DR: In this article, useful expressions to describe the thermal sputtering for materials having a temperature dependent thermal diffusivity, using a heat capacity and thermal conductivity which vary as C = C 0 T n−1 and K = K 0 m−1, respectively, and assigning a width to the initial temperature distribution.
Abstract: Recent experiments on the erosion of condensed gases and alkali halides by incident ions have renewed interest in the description of thermal spikes. In such spikes a localized, transiently heated region produced by incident radiation may induce activated processes like evaporation of atoms or molecules from a surface. In this paper are presented useful expressions to describe the thermal sputtering for materials having a temperature dependent thermal diffusivity, using a heat capacity and thermal conductivity which vary as C = C 0 T n–1 and K = K 0 m–1, respectively, and assigning a width to the initial temperature distribution.
TL;DR: In this paper, the effects of bias voltages on electrical properties such as the resistivity ϱ, the differential change in resistivity with respect to temperature dϱ/dT, the Hall coefficients and the superconductivity were studied in terms of the structural features of the films prepared.
TL;DR: In this paper, optical absorption and emission spectroscopies were used for in situ investigations of process occuring in the plasma and at the electrode-gas interfaces which control the reactive sputter etching of indium targets and the reactive deposition of InN films in mixed Ar-N 2 glow discharges.
TL;DR: In this paper, a thermal spike model was used to model the sputtering of frozen gases by MeV ions. But the model is not consistent with the experimental observations, and the experimental results show that a localized cylindrical region around each incident ion track is raised to a temperature sufficiently high to evaporate a significant quantity of the frozen gas film.
Abstract: Recent measurements of the sputtering of frozen gases by MeV ions exhibit yields that are several orders of magnitude larger than predicted by collision cascade theory. Of the models considered, only a “thermal spike” model is consistent with our experimental observations. The various experimental parameters studied include the energy (0.3–2.0 MeV), atomic number (H+. He+. N+ and Ar+). angle of incidence and current density of the incident ion beam. the thermal conductivity of the substrate, and the temperature and thickness of the frozen film. Calculations for 1.0 MeV He + in Xe. based on a thermal spike mechanism, indicate that a localized cylindrical region around each incident ion track is raised to a temperature sufficiently high to evaporate a significant quantity of the frozen gas film.
TL;DR: In this paper, the effects of low-energy ion bombardment on enhancing elemental diffusion rates at both heterojunction interfaces during film deposition and over the compositionally altered layer created during sputter etching alloy targets have been considered.
Abstract: The effects of low‐energy ion bombardment on enhancing elemental diffusion rates at both heterojunction interfaces during film deposition and over the compositionally altered layer created during sputter etching alloy targets have been considered. Depth dependent enhanced interdiffusion coefficients, expressed as D*(x)=D*(0) exp(−x/Ld), where D*(0) is more than five orders of magnitude greater than thermal diffusion values, were measured in InSb/GaSb multilayer structures deposited by multitarget bias sputering. D*(0) was determined from the amplitude u of the compositional modulation in the multilayered films (layer thicknesses between 20 and 45 A) as measured by superlattice x‐ray diffraction techniques. The value of D*(0) was found to increase from 3×10−17 to 1×10−16 cm2/sec as the applied substrate bias was increased from 0 to −75 V. However even at Va=0, the diffusion coefficient was enhanced owing to an induced substrate potential with respect to the positive space‐charge region in the Ar discharge....
TL;DR: In this paper, the angular etch dependence of a directional reactive ion etch (RIE) at oblique angles has been investigated using a simple grid-covered structure (Faraday cage) in conventional parallel plate sputter etching equipment.
Abstract: Directional reactive ion etching (RIE) at oblique angles is possible using a simple grid‐covered structure (Faraday cage) in conventional parallel‐plate sputter etching equipment. Oblique‐angle etching, as is possible in any ion‐beam system, has been demonstrated using the etchant ions from CHF3 gas on a fused‐silica substrate. The first detailed measurements of the angular etch dependence of RIE show a strong similarity to those of an ion‐beam system (no chemical etching).
TL;DR: In this paper, the present state of quantitative secondary ion mass spectrometry (SIMS) is analyzed critically, and the implications brought about by a fixed experimental geometry and by the mass dependence of instrumental factors are discussed in detail.
TL;DR: In this paper, it was shown that sputtered indium-tin oxide (ITO)/InP solar cells with large lattice mismatch have the same efficiency as CdS/InP junctions with good lattice match.
Abstract: The reason that sputtered indium‐tin oxide (ITO)/InP solar cells junctions with large lattice mismatch have the same efficiency as CdS/InP junctions with good lattice match is shown to be that sputtered ITO/InP junctions actually consist of n+‐ITO/n‐InP/p‐InP buried homojunctions. To demonstrate this and to show that the homojunction formation is caused by thermal damage to the InP surface during sputtering deposition rather than from impurity diffusion from the oxide, a series of five different metal oxide/InP junctions have been formed by sputtering of the oxide, all with high solar efficiency. Junctions have been prepared both from single‐crystal InP : Cd and from epitaxial crystal films of InP : Zn. The effects of sputter deposition of the oxide have been simulated by sputter etching of the InP surface, and the effects analyzed through measurements of the properties of Au/InP junctions, and of the Hall effect and photoluminescence of InP surfaces. Some heat treatment of the sputtered cells is required...
TL;DR: In this article, the influence of the anisotropy of the momentum recoil density of collision cascades in solids on the energy and angular distribution of sputtered particles is considered.
Abstract: The influence of the anisotropy of the momentum recoil density of collision cascades in solids on the energy and angular distribution of sputtered particles is considered. Various sputtering mechanisms are discussed. For some of those mechanisms this anisotropy leads to deviations from a e−2 asymptotic form in the energy distribution and to an asymmetry in the angular distribution as a function of the angle of incidence of the projectile.
Patent•
15 Sep 1980
TL;DR: In this article, a method and apparatus for sputtering an element with a magnetron plasma source where a plasma is formed between two electrostatic field defining surfaces of the source and a generator anode disposed adjacent the plasma ejects it toward the element to be sputtered.
Abstract: Method and apparatus for sputtering an element with a magnetron plasma source where a plasma is formed between two electrostatic field defining surfaces of the source and a generator anode disposed adjacent the plasma ejects it toward the element to be sputtered. Various applications are described including selective coating of substrates of different electrical conductivity, substrate cleaning, ion milling, retrieval of expensive or dangerous coating materials, heating with little loss in the heat source, sputtering with reactive ions, sensitization or charge neutralization, and pumping of active gases.