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Ion plating deposits thin film on complex surface in one operation. The ionized materials follow electric lines of force to all points on the objects, uniformly plating the surface from all sides simultaneously.
A system for depositing a thin film of one material on another is described. A mass filter is interposed between the source of material being deposited and the object upon which deposition is being made.
Means and methods of depositing thin films on substrates
Thickness monitoring technique for thin films, using silicon solar cell mounted adjacent to substrate with iron deposition
Copper indium disulfide thin films were deposited via aerosol-assisted chemical vapor deposition using single source precursors. Processing and post-processing parameters were varied in order to modify morphology, stoichiometry, crystallography, electrical properties, and optical properties in order to optimize device-quality material. Growth at atmospheric pressure in a horizontal hot-wall reactor at 395 C yielded best device films. Placing the susceptor closer to the evaporation zone and flowing a more precursor-rich carrier gas through the reactor yielded shinier, smoother, denser-looking films. Growth of (112)-oriented films yielded more Cu-rich films with fewer secondary phases than growth of (204)/(220)-oriented films. Post-deposition sulfur-vapor annealing enhanced stoichiometry and crystallinity of the films. Photoluminescence studies revealed four major emission bands (1.45, 1.43, 1.37, and 1.32 eV) and a broad band associated with deep defects. The highest device efficiency for an aerosol-assisted chemical vapor deposited cell was 1.03 percent.
The deposition of semiconducting and insulating thin films at low temperatures using microwave technology was explored. The method of plasma formations, selection of a power source, the design of the microwave plasma cavity, the microwave circuitry, impedance matching, plasma diagnostics, the deposition chamber and the vacuum system were studied.
Ion beam sputter-deposited thin films of Al2O3, SiO2, and a codeposited mixture of predominantly SiO2 with small amounts of a fluoropolymer were evaluated both in laboratory plasma ashing tests and in space on board shuttle flight STS-8 for effectiveness in preventing oxidation of polyimide Kapton. Measurements of mass loss and optical performance of coated and uncoated polyimide samples exposed to the low Earth orbital environment are presented. Optical techniques were used to measure loss rates of protective films exposed to atomic oxygen. Results of the analysis of the space flight exposed samples indicate that thin film metal oxide coatings are very effective in protecting the polyimide. Metal oxide coatings with a small amount of fluoropolymer codeposited have the additional benefit of great flexibility.
Ion beam sputter-deposited thin films at Al2O3, SiO2, and a codeposited mixture of predominantly SiO2 with small amounts of fluoropolymer were evaluated both in laboratory plasma ashing tests and in space on board Shuttle flight STS-8 for effectiveness in preventing oxidation of polyimide Kapton. Measurements of mass loss and optical performance of coated and uncoated polyimide samples exposed to the low earth orbital environment are presented. Optical techniques were used to measure loss rates of protective films exposed to atomic oxygen. Results of the analysis of the space flight exposed samples indicate that thin film metal oxide coatings are very effective in protecting the polyimide. Metal oxide coatings with a small amount of fluoropolymer codeposited have the additional benefit of great flexibility.
A simple, inexpensive circuit is described for switching the current through a resistively heated evaporation boat during thin-film deposition. The circuit uses a silicon-controlled rectifier (SCR) to switch the 0-15-A current in the primary of a 2-kV A step-down transformer that supplies the 0-200-A current to an evaporation boat. The circuit is controlled by a 0-10 V-dc signal similar to that furnished by an Inficon XTC deposition-rate controller. This circuit may be assembled from a handful of parts for a cost of about $400, nearly one-tenth the cost of similar commercial units. Minimum construction is required, since the circuit is built around an off-the-shelf, self-contained SCR unit.
Thin film silicon monoxide capacitor vacuum deposition and intact removal from substrate to study breakdown characteristics
Feasibility of laser deposited metal films for mirror production
A series of FORTRAN-77 programs is described which correct for the effect of a conducting substrate when a linear four-point probe is used to measure the resistivity of a thin film. The resistivity of the film is given in terms of the thicknesses of the film and substrate, the known resistivity of the substrate, and the measured delta V/I. A full development is given as well as a complete description of the operation of the programs. The programs themselves can be obtained through COSMIC, and are identified as LEW No. 14381.
A state-of-the-art research laboratory was established to grow and characterize amorphous thin films that are useful in semi-conductor devices. Two film systems, nitride films and silicon dioxide films were studied. Over seventy deposition runs for nitride films were made. The films were deposited on silicon substrate using plasma enhanced chemical vapor deposition. It was found that the uniformity of the films were affected by the location of the film on the platen.
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Ion plating technique keeps the substrate surface clean until the film is deposited, allows extensive diffusion and chemical reaction, and joins insoluble or incompatible materials. The technique involves the deposition of ions on the substrate surface while it is being bombarded with inert gas ions.
Amorphous and microcrystalline silicon carbon films (a-SiC:H, micro-c-SiC:H) have been deposited using SiH4, CH4 and H2 mixed gas ECR (electron cyclotron resonance) plasmas. The optical bandgap of a-SiC:H films is not dependent on the hydrogen dilution in the ECR plasma. The deposition rate of a-SiC:H films is found to be strongly dependent on the ECR magnetic field and the hydrogen dilution. The hydrogen dilution effect on the deposition rate indicates that the etching in ECR hydrogen plasmas plays an important role in the deposition of a-SiC:H films. The optical constants n and k of ECR-deposited a-SiC:H films in the wavelength region of 0.4 to 1.0 micron are determined to be 2.03-1.90 and 0.04-0.00, respectively. The microstructures of ECR-deposited micro-c-SiC:H films are shown by X-ray diffraction and SEM (scanning electron microscopy) to be composed of 1000-A alpha-SiC microcrystallites and amorphous network structures.
ErBa2Cu3O(7-x) films have been produced by simultaneous deposition of Er, Ba, and Cu from three ionized cluster beam (ICB) sources at acceleration voltages of 0.3 to 0.5 kV. Combining ozone oxidation with ICB deposition at 650 C eliminated any need of post annealing processing. The substrates were rotated at 10 rotations per minute during the deposition which took place at a rate of about 3 to 4 nm. Films with areas up to 70 mm in diameter have been made by ICB deposition. These films, 100 nm thick, were deposited on SrTiO3 (100) substrates at 650 C in a mixture of six percent O3 in O2 at a total pressure of 4 x 10(exp -4) Torr. They had T(sub c) ranging from 84.3 K to 86.8 K over a 70 mm diameter and J(sub c) above 10(exp 6) A/sq cm at 77 K. X ray diffraction measurements of the three samples showed preferential c-axis orientation normal to the substrate surface. Scanning electron micrographs (SEM) of the three samples also show some texture dependence on sample position. For the three samples, there is a correlation between SEM texture, full width at half-maximum of rocking curves and J(sub c) versus temperature curves.
Ionized cluster beam (ICB) deposition is employed to produce ErBa2Cu3O(7-x) films on different substrates without post-annealing. Films with diameters of up to 70 mm are grown on SrTiO3 100 plane and exhibit Tc values of 84-87 K, Jc of about 10 exp 6 A/sq m at 77 K. These films are epitaxial with the c-axis perpendicular to the plane of the substrate surface, and they can be routinely produced by ICB with good Jc and Tc.