Showing papers on "Sputter deposition published in 1986"

On structure and properties of sputtered Ti and Al based hard compound films

Abstract: After investigating basic correlations between process and film characteristics in previous works new multicomponent hard coatings, on the basis of Ti–Al and Ti–Zr, have been deposited by magnetron sputtering. These ternary and quaternary nitrides are crystallizing in a face centered cubic TiN lattice with reduced or enlarged lattice parameters depending on the amount and the radius of foreign atoms. Improved wear behavior compared to chemical vapor deposition (CVD) TiN coatings has been stated with (Ti,Al)N, (Ti,Zr)N, and (Ti,Al,V)N coatings. According to these results the development of the coating material itself will be of major interest in the future.

Ferroelectric (Pb,La)(Zr,Ti)O3 epitaxial thin films on sapphire grown by rf-planar magnetron sputtering

Abstract: Ferroelectric (Pb,La)(Zr,Ti)O3 (PLZT) thin films have been epitaxially grown on the c plane of sapphire by rf‐planar magnetron sputtering. The sputtering conditions were investigated to obtain epitaxial and transparent films. Dielectric, piezoelectric, and electro‐optic properties of the films were measured. Piezoelectricity of the PLZT(28/0/100) film was confirmed and was as strong as that of BaTiO3. Excellent quadratic electro‐optic effects for PLZT(28/0/100) and PLZT(9/65/35) films and a linear electro‐optic effect for PLZT(21/0/100) film were observed at 0.633‐μm wavelength. Epitaxial PLZT thin film on sapphire is presently the most promising material for new functional devices.

Interlayer dielectric process

Abstract: A method for producing a film over a topologically non-planar surface of a material which has a sputter etch rate which is higher in a direction parallel to the plane of the wafer than in a direction perpendicular to the plane of the wafer. Key steps in the process include first, depositing the material by plasma enhanced chemical vapor deposition while simultaneously sputter etching it. Then second, sputter etching the material. Using this two step process, a substantially conformal or sloped film is produced by repeating the steps consecutively until the desired thickness is obtained. The film can then be substantially planarized if desired, by an extended sputter etch to selectively remove material having a sloped surface rather than a flat surface, since the etch rate is higher parallel to the plane of the wafer than perpendicular to the wafer. If a thicker planar surface is desired, additional material can then be deposited by steps of simultaneous plasma chemical vapor deposition and sputter etch, or by consecutive steps of simultaneous plasma deposition and sputter etch followed by sputter etching.

Method for forming Cu In Se2 films

Abstract: A method for fabricating a copper indium diselenide semiconductor film comprising use of DC magnetron sputtering apparatus to sequentially deposit a first film of copper on a substrate and a second film of indium on the copper film. Thereafter the substrate with copper and indium films is heated in the presence of gas containing selenium at a temperature selected to cause interdiffusion of the elements and formation of a high quality copper indium diselenide film. In a preferred form, an insulating substrate is used and an electrical contact is first deposited thereon in the same DC magnetron sputtering apparatus prior to deposition of the copper and indium films.

Morphology and properties of sputtered (Ti,Al)N layers on high speed steel substrates as a function of deposition temperature and sputtering atmosphere

Abstract: (Ti,Al)N layers were prepared by reactive dc and radio‐frequency (rf) magnetron sputtering onto polished flat high speed steel (HSS) surfaces. The rectangular samples were mounted on a special sample holder providing a temperature gradient in the range of 500 °C to room temperature along the length of the sample. The (Ti,Al)N layers were deposited at various N2 and Ar pressures. The target was a Ti–50 at. % Al alloy. The film morphology and composition was observed by scanning electron microscopy (SEM) and Auger electron spectroscopy (AES), respectively, and correlated to mechanical properties like hardness and critical load (scratch test). The results are discussed with the respect of the sputtering conditions.

Electrochromic hydrated nickel oxide coatings for energy efficient windows: Optical properties and coloration mechanism

Abstract: Durable electrochromic coatings of hydrated nickel oxide were produced by reactive rf magnetron sputtering of Ni followed by treatment in KOH. Spectrophotometry was used to assess the achievable modulation of luminous and solar transmittance and to verify that the studied material is interesting for ‘‘smart window’’ applications. 15N nuclear reaction analysis suggested that coloration occurred upon hydrogen extraction.

Highly Conductive and Transparent Silicon Doped Zinc Oxide Thin Films Prepared by RF Magnetron Sputtering

Abstract: Highly conductive and transparent films of Si-doped ZnO have been prepared by rf magnetron sputtering of a ZnO target with SiO2 or SiO dopant added. Films with resistivity as low as 3.8×10-4 Ω cm and average transmittance above 85% in the visible region can be produced on low temperture substrates at below 250°C. Great improvement in the stability of the resistivity for use at high temperatures was obtained for Si-doped ZnO films in comparison with undoped films.

Applications of Monte Carlo simulation in the analysis of a sputter‐deposition process

Abstract: Practicality of the Monte Carlo (MC) method developed for the analysis of the particle transport process in sputter‐deposition was examined. Titanium film thickness distributions on both faces of a planar substrate facing and not facing a planar‐magnetron‐type target were compared with corresponding calculated profiles. The results show that sufficient performance of the MC method can be obtained in the usual sputtering condition up to the argon pressure beyond which the majority of particles are transported by the thermal diffusion process.

Sputter module for modular wafer processing system

Abstract: A machine for sputter deposition of a wafer workpiece also sputters on the wafer supporting mechanism. This causes a need for cleaning or replacement of the support mechanism. A sputter machine is provided in which the supporting mechanism can be isolated from the sputtering source, the pumps and other processing apparatus for cleaning without exposing the entire machine to atmosphere.

Wear-protected device

Abstract: A hard carbon film (12) is formed by ion-beam sputtering on a surface of a substrate (11) such as glass lens or metal sheet of a magnetic disk or a plastic film of a magnetic video tape, by selecting the direction of the ion-beam in the sputtering process to be parallel with surface of the substrate (11) of a magnetic disk, and subsequently theroen a lubricative film (13), such as ZnS 2 is formed also by ion-beam sputtering.

Multiple ion source method and apparatus for fabricating multilayer optical films

Abstract: A method of fabricating multiple layer, solid, thin films on a substrate having a surface to be coated, the method providing control over the thickness, stoichiometry, and morphology of each separate layer formed by a method comprising steps: A. forming a first ion beam from an inert gas; B, bombarding a target surface with said first ion beam in a vacuum chamber to generate a vapor cloud composed of the target material atoms by the process of sputtering; C. adjusting the respective positions of the substrate surface for coating and the target surface to promote the condensation of the vapor upon the substrate surface for coating; D. forming a second ion beam, the second ion beam's ions being formed from a mixture of inert and reactive gases; E. bombarding the substrate surface simultaneously with the second ion beam to promote a chemical reaction between the target vapor atoms and the chemically reactive gas ions as the target atoms and the chemically reactive gas ions impinge upon the substrate surface for coating, the resulting chemical compound building up in thickness as a homogeneous thin solid film layer; F. positioning an alternative target material in the place occupied by the previous one; G. repeating the above method steps to produce each successive thin solid film layer of different material formed upon each previous layer.

Cross-section preparation for TEM of film-substrate combinations with a large difference in sputtering yields

Abstract: The preparation of cross-section samples of thin films for TEM, may be difficult and tedious, especially if the difference in chemical or physical etching rates is large between the film and the substrate. In this paper, a method is presented whereby cross-sections can be prepared even if the film and the substrate have a large difference in sputtering yield. By utilizing the strong angular dependence of the sputtering yield and sputter at a low ion incidence angle with respect to the substrate surface of 7–12° and, furthermore, by avoiding sputtering parallel to the interface, samples with homogeneous thickness can be obtained. The technique is demonstrated on reactively sputtered titanium nitride coatings on high speed steel substrates. The difference in sputtering yields is about three for this film-substrate combination with the substrate being sputtered fastest.

Hollow‐cathode‐enhanced magnetron sputtering

Abstract: A hollow cathode arc electron source has been added to a conventional planar magnetron sputtering system to form a triode magnetron. The hollow cathode source was chosen in place of a filament for high emission current at low energy, lifetime, and ease of operation in high magnetic fields and reactive gases. The electrons emitted from the hollow cathode produced additional gas ionization, resulting in a denser plasma at constant voltage. Up to 60% of the hollow cathode emission current could be directly coupled into the discharge current of the magnetron. Increases in the discharge current and the deposition rate of up to 10× were recorded over the conventional magnetron at the same voltage. The hollow cathode enhanced magnetron discharges were also capable of high current operation at voltages down to 20 V, which is below the sputter threshold. The pressure of operation could also be reduced significantly, and the magnetron could be operated at full power as low as 5×10−5 Torr in argon.

Reactive radio frequency sputter deposition of higher nitrides of titanium, zirconium, and hafnium

Abstract: Higher nitrides of Ti, Zr, and Hf have been prepared by reactive rf sputtering of Ti, Zr, and Hf metals in a pure nitrogen atmosphere. The electrical and optical properties of these films are highly dependent on two deposition parameters, namely, the substrate temperature and the target voltage. We find that at each particular target voltage, there exists a critical temperature below which the higher nitride phase can be deposited and above which the phase cannot form. This suggests that the higher nitride phase (which is speculated to be an ordered defect structure) is metastable and is not energetically favored at high processing temperature or at high input power. At 2000 V target voltage, this critical temperature is determined to be approximately 200 °C for Hf–N, 25 °C for Zr–N, and is unknown for Ti–N system. The optical band gap of the ZrNx films decreases from 5.31 to 1.66 eV as the substrate temperature varies from −196 to 750 °C. Thermal analyses, using modulated beam mass spectrometry for monit...

Anisotropy induced signal waveform modulation of DC magnetron sputtered thin film disks

Abstract: Thin films of Co-alloy, intended for use in longitudinal recording, were deposited onto variously prepared substrates by in-line DC magnetron sputtering. An anisotropy induced signal waveform modulation was observed through the use of a disk certifier and verified with vibrating sample magnetometer (VSM) orientation measurements and electron microscopic observation of grain structure. The partial low angle of incidence which can occur in in-line sputtering, the magnetic field generated from the magnetron target, the surface topography of substrates and the sputtering conditions, all affected the extent of preferred anisotropy in the films. By minimizing low angle of incidence sputtering, texturing the substrate surface circumferentially, and adjusting the processing conditions, we can eliminate not only the signal waveform modulation but also enhance the magnetic properties.

The use of nitrogen flow as a deposition rate control in reactive sputtering

Abstract: It is well known in reactive sputtering that the deposition rate generally drops drastically at a high enough partial pressure level of the active gas to form a compound on the target surface At the point where the deposition rate drops, there exists a simple relationship between the consumed nitrogen and the deposition rate of stoichiometric films This abrupt decrease in deposition rate can be measured indirectly by monitoring the processing gas by mass spectroscopy (MS) and studying the discharge by optical emission spectroscopy (OES) We have shown that it is possible to select a desired deposition rate by simply choosing a correct mass flow value of the active gas (nitrogen) while maintaining correct stoichiometry of the sputtered film This can be achieved by presetting the mass flow of the nitrogen Thereafter, the rf power is increased to the transition level, where the surface of the target changes from compound to elemental The combination of mass flow control and diagnostic tools (MS) and (OES) enables precise control of the process

Thermal stability of heat‐reflective films consisting of oxide–Ag–oxide deposited by dc magnetron sputtering

Abstract: Transparent heat‐reflective films consisting of ITO–Ag–ITO or ZnO–Ag–ZnO were deposited onto soda‐lime glass by dc magnetron sputtering. In particular, the oxide layers were deposited from an electrically conductive oxide target. The transmittance in the visible range of the ITO–Ag–ITO film was more than 80% and the reflectance at 10 μm was nearly 95%. After the heat treatment at 650 °C, the transmittance of the films increased to nearly 85% and the reflectance at 10 μm was the same value of 95% as it was before the heat treatment. Moreover, the sheet resistance decreased to less than 4 Ω/cm2 by the heat treatment. Further, there were no visual changes or damage to the film up to 650 °C. The results showed that the ITO–Ag–ITO film was durable for the glass bending process. The ZnO–Ag–ZnO film also had high transmittance in the visible range and high reflectance in the infrared range, i.e., the transmittance in the visible range was more than 80% and the reflectance at 10 μm was 95%. However, these properties are much deteriorated by the heat treatment as compared with those of the ITO–Ag–ITO film.

Thin film thermocouples for internal combustion engines

Abstract: The feasibility of fabricating thin film thermocouples on internal combustion engine hardware was investigated. The goal was to find a procedure that would be useful for the measurement of the surface metal temperature of valves, valve seats, combustion chamber surfaces, cylinder walls, and piston heads during engine operation. The approach pursued was to coat the engine hardware material with an aluminum‐containing, oxidation‐resistant ferrous alloy (FeCrAlY) which forms a thermal oxide layer with good electrical resistance. This thermal oxide was coated with a thin layer of reactively sputtered aluminum oxide and sputtered thin film type S thermocouple legs of platinum and platinum plus rhodium. This project was used to investigate the materials problems related to obtaining good adhesion in the metal/metal–oxide/oxide/metal laminate and the electrical insulating properties of the oxide. Thermal oxidation, reactive sputtering of Al2O3, and platinum alloy sputtering were investigated using optical micros...

Correlation between process conditions, chemical composition and morphology of MoS2 films prepared by RF planar magnetron sputtering

Abstract: MoS2 films have been prepared by RF sputtering in a planar magnetron system. Their chemical composition was analysed by energy dispersive X-ray spectroscopy. The morphology and growth characteristics were examined by scanning and transmission electron microscopy and by electron diffraction. Correlation between process conditions, film stoichiometry and morphology has been pointed out by a systematic variation of the experimental sputter parameters with emphasis on a stable substrate temperature during deposition. It has been shown that by a precise control of the substrate temperature specific morphologies can be obtained which are independent of film thickness. In particular, at high deposition temperature the films exhibit a lamellar-type microstructure with the 002 planes of the MoS2 crystallites perpendicular to the substrate. The crystallite size strongly decreases for deposition at lower temperature. The increase of power density was found to give higher sulphur concentration in the films whereas substrate biasing results in a pronounced excess of the metallic element.

System and method for depositing plural thin film layers on a substrate

Abstract: A sealed substrate processing path has a plural selectably isolatable vacuum deposition chambers (12, 14, 16, 18, 20 and 22) along the path. A transporter carries substrates along the path and an independently controllable sputter deposition is performed in each deposition chamber (14, 16, 18, and 20) on substrate therein. Substrates are loaded from a load chamber (12) to a first deposition chamber (14) while vacuum is maintained in the first deposition chamber (14) and load chamber (12). Substrates are transferred from a last deposition chamber (20) to an unloaded chamber (22) while a vacuum is maintained in the last (20) and unload (22) chambers. Substrates are placed in the load chamber (12) while the load (12) and first (14) chamber are isolated and are removed from the unload chamber (22) while the last (20) and unload (22) chambers are isolated. In one embodiment, substrates travel successively from the load chamber (12) to first (14) through fourth (20) deposition chambers and then to unload chamber (22). In another embodiment, substrates travel from the load chamber (12) to first (14) to second (16) to first (14) and to third (18) deposition chambers and then to the unload chamber (22).

Characterization of reactively sputtered WNx film as a gate metal for self‐alignment GaAs metal–semiconductor field effect transistors

Abstract: Properties of reactively sputtered WNx films on a GaAs substrate have been investigated by electrical and physical analyses. WNx films were deposited from a pure W target by using three types of sputtering systems: (1) Magnetron sputtering system equipped with rf and dc mode; (2) S‐gun sputtering system; (3) rf diode sputtering system. The composition of WNx films was easily and reproducibly controlled by changing the N2 content in Ar–N2 mixed ambient gas. The WNx–GaAs system was both electrically and metallurgically stable even after high‐temperature annealing of up to 800 °C. The Schottky barrier height to n‐type GaAs was more than 0.8 V, which is the highest value obtained so far among any other refractory metals. Self‐aligned GaAs MESFET’s were successfully fabricated using a WNx gate. The transconductance was typically 150 mS/mm for 1.5 μm gate length.

Process for equipment to coat tools for machining and forming techniques with mechanically resistant layers

Abstract: Process and apparatus for coating a tool with a layer of a compound which contains at least one of carbon and nitrogen and at least one of titanium, zirconium, chromium, tungsten, tantalum, vanadium, niobium, hafnium and molybdenum. The apparatus includes a vacuum chamber and a substrate holder for accommodating at least one tool with the substrate holder at a bias of between -40 and -200 V relative to ground. The apparatus includes at least two magnetron sputtering cathodes disposed in mirror symmetry to the substrate holder. The target contains at least one metal selected from the group consisting of T, Zr, Cr, W, Ta, V, Nb, Hf and Mo. The apparatus includes at least one gas source for supplying the vacuum chamber with a noble gas and a reaction gas. The reaction gas contains at least one of nitrogen and a gaseous carbon compound. The apparatus includes at least one anode in the edge region of each target so that the anodes are positioned in mirror symmetry with respect to the target holder. Each of the anodes is connected to a voltage means for applying a voltage of +10 to +200 V relative to ground.

Tribological properties of MoNx coatings in contact with copper

Abstract: In metal forming processes, coatings can be used to prevent adhesion between the tool and the workpiece in order to increase the lifetime of the tool. A new promising coating material for copper forming tools is MoNx, which has low galling tendency in an unlubricated contact with copper. MoNx coatings were deposited in a magnetron sputtering system. Tribological tests were carried out in a pin‐on‐disk tribometer. Also the adhesion and structure of the coatings were characterized. The lowest coefficient of friction and the lowest wear rate against copper was measured when the nitrogen concentration in the coating was 15 at. %–18 at. % and the Vickers microhardness about 2000 HV at a load of 10 g.

An interferometric investigation of the thermalization of copper atoms in a magnetron sputtering discharge

Abstract: The average kinetic energy of the atoms sputtered from the copper cathode of a magnetron sputtering discharge has been deduced from the shapes of their Doppler‐broadened emission lines, which were measured with a high‐resolution scanning Fabry–Perot interferometer. At a fixed distance from the cathode the energy decreased with increasing sputtering gas pressure, as expected. The experimental points fell between the theoretical curves of Westwood [J. Vac. Sci. Technol. 15, 1 (1978)], and Meyer, Schuller, and Falco [J. Appl. Phys. 52, 5803 (1981)] lying somewhat closer to the former than to the latter.

Growth of silicon homoepitaxial thin films by ultrahigh vacuum ion beam sputter deposition

Abstract: Silicon homoepitaxial films have been grown by ion beam sputter deposition using an ultrahigh vacuum (UHV) apparatus with in situ diagnostic equipment. The deposition conditions are characterized and the beginning of single crystal growth occurs at 250 °C. Films of high crystalline and morphological quality are obtained at deposition temperatures above 700 °C, where good doping element transfer efficiency from the target to the film is observed. Room temperature bulk mobility is found for film thicknesses as low as 0.5 μm and deposition temperatures near 700 °C.