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Process technology for linear integrated circuits
A B S T R A C T S ON M I C R O E L E C T R O N I C S AND R E L I A B I L I T Y
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surface of the films were found to be greater than the bulk value. This was interpreted as being at least partly due to the presence of compressive stresses. The effects of annealing in an Ar-H atmosphere were studied in terms of diffraction line width, lattice parameter and resistivity.
Deposition parameter effects on vapeur-deposited z i n c films. R. M. LUMLEYand J. D. Woov, Trans. MetalL Soc. AIME, 236, March (1966), p. 326. In this investigation, polyethylene terephthalate (Mylar) was coated with various thicknesses of a vapour-deposited silver precoat followed by a vapourdeposited zinc using several orders of magnitude variation in deposition rate of both the silver and zinc. The grain size and resistivity of the zinc film was primarily a function of the silver-precoat thickness (in the range of 0.001-10 A average Ag precoat thickness) and a secondary function of the zinc film thickness. The silver and zinc deposition rates were found to have a minor effect on the characteristics of the zinc film. Electron and X-ray diffraction results showed that all zinc films exhibited a fibre texture with the <001 > axes essentially perpendicular to the plane of the film. Process technology for linear integrated circuits. N. A. CHEVLI,Trans. Metall. Soc. AIME, 236, March (1966), p. 369. Exploratory work was conducted in the fabrication of integrated circuitry, specifically linear amplifier circuits, by three general methods: (1) monolithic diffused silicon; (2) a combination of metal thin-film and monolithic diffused silicon; and (3) a hybrid of metal films and diffused silicon on an alumina substrate. In these linear amplifier integrated circuits the following conditions were desired: very high-frequency response, high voltage gain and good thermal tracking stability of electrical characteristics. The resulting circuit designs imposed problems of isolation between elements, layout and smallness of size of active elements; and close tolerances on electrical characteristics of the passive elements. Interconnexion problems for specific designs resulted from the small dimensions involved and the topography of the hybrid fabrication techniques. The desired integratedcircuit characteristics were achieved with the technologies of categories (2) and (3) above. Solutions to the problems imposed by these characteristics lay in the ability to isolate circuit elements of small size while providing a layout designed to minimize element-to-element variations. Sufficient freedom in the formation of passive elements was achieved by uniting the metal film and the monolithic silicon technologies. The most satisfactory designs were based on the beam-lead interconnection and isolation technique. The deposition o f siHcon upon sapphire substrates. P. H. ROBINSONand C. W. MUELLER,Trans. Metall. Soc..4IME, 236, March (1966), p. 268. A technique was developed for depositing single-crystal films of silicon on single-crystal sapphire substrates via the pyrolytic decomposition of S i H J H 2 mixtures. Electron diffraction and X-ray Laue reflection examinations of these films revealed single-crystal patterns. These films were characterized by measuring conductivity type, thickness, resistivity and Hall mobility. Chemical etching, dislocation staining and electron-microscopy examination have indicated the presence of low-angle grain boundaries and microtwinning in the silicon films. The role of the sapphire substrate with respect to its quality, orientation, surface finish, and thermal and chemical treatment was investigated. Hall mobility as a function of sapphire orientation was measured. A mobility equal to 88 per cent of bulk silicon mobility was attained. Insulated-gate field-effect transistors which have a transconductance of 4000 ~ mho at 6 mA were fabricated using these films. Temperature coefficients of resistance of evaporated th;n films. ANITA CALCATELLIand G. CERUTTI,Vacuum, 16, No. 7 (1966), p. 373. Variations in the electrical resistance of thin films heated in air with time and temperature were examined. The films were prepared by evaporating a chromiumsilicon powder. Tests carried out at high temperatures showed the influence of various substrates on the film resistance values at which inversion of the sign of the temperature coefficient of resistance (TCR) occurs. The results showed that films on substrates of silica glass and mica continue to be conductors at temperatures approaching 300°C whilst those on substrates of SAP (synterized aluminium powder) can sometimes go beyond such limits and in some cases reach 500°C. Properties and structure of thin silicon films sputtered on fused quartz substrates. H. Y. KUMAGAI,J. M. THOMPSON and G. KRAUSS, Trans. Metall. Soc. AIME, 236, March (1966), p. 295. Boron-doped p-type and arsenic-doped n-type source materials were used to deposit thin silicon films
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surface of the films were found to be greater than the bulk value. This was interpreted as being at least partly due to the presence of compressive stresses. The effects of annealing in an Ar-H atmosphere were studied in terms of diffraction line width, lattice parameter and resistivity.
Deposition parameter effects on vapeur-deposited z i n c films. R. M. LUMLEYand J. D. Woov, Trans. MetalL Soc. AIME, 236, March (1966), p. 326. In this investigation, polyethylene terephthalate (Mylar) was coated with various thicknesses of a vapour-deposited silver precoat followed by a vapourdeposited zinc using several orders of magnitude variation in deposition rate of both the silver and zinc. The grain size and resistivity of the zinc film was primarily a function of the silver-precoat thickness (in the range of 0.001-10 A average Ag precoat thickness) and a secondary function of the zinc film thickness. The silver and zinc deposition rates were found to have a minor effect on the characteristics of the zinc film. Electron and X-ray diffraction results showed that all zinc films exhibited a fibre texture with the <001 > axes essentially perpendicular to the plane of the film. Process technology for linear integrated circuits. N. A. CHEVLI,Trans. Metall. Soc. AIME, 236, March (1966), p. 369. Exploratory work was conducted in the fabrication of integrated circuitry, specifically linear amplifier circuits, by three general methods: (1) monolithic diffused silicon; (2) a combination of metal thin-film and monolithic diffused silicon; and (3) a hybrid of metal films and diffused silicon on an alumina substrate. In these linear amplifier integrated circuits the following conditions were desired: very high-frequency response, high voltage gain and good thermal tracking stability of electrical characteristics. The resulting circuit designs imposed problems of isolation between elements, layout and smallness of size of active elements; and close tolerances on electrical characteristics of the passive elements. Interconnexion problems for specific designs resulted from the small dimensions involved and the topography of the hybrid fabrication techniques. The desired integratedcircuit characteristics were achieved with the technologies of categories (2) and (3) above. Solutions to the problems imposed by these characteristics lay in the ability to isolate circuit elements of small size while providing a layout designed to minimize element-to-element variations. Sufficient freedom in the formation of passive elements was achieved by uniting the metal film and the monolithic silicon technologies. The most satisfactory designs were based on the beam-lead interconnection and isolation technique. The deposition o f siHcon upon sapphire substrates. P. H. ROBINSONand C. W. MUELLER,Trans. Metall. Soc..4IME, 236, March (1966), p. 268. A technique was developed for depositing single-crystal films of silicon on single-crystal sapphire substrates via the pyrolytic decomposition of S i H J H 2 mixtures. Electron diffraction and X-ray Laue reflection examinations of these films revealed single-crystal patterns. These films were characterized by measuring conductivity type, thickness, resistivity and Hall mobility. Chemical etching, dislocation staining and electron-microscopy examination have indicated the presence of low-angle grain boundaries and microtwinning in the silicon films. The role of the sapphire substrate with respect to its quality, orientation, surface finish, and thermal and chemical treatment was investigated. Hall mobility as a function of sapphire orientation was measured. A mobility equal to 88 per cent of bulk silicon mobility was attained. Insulated-gate field-effect transistors which have a transconductance of 4000 ~ mho at 6 mA were fabricated using these films. Temperature coefficients of resistance of evaporated th;n films. ANITA CALCATELLIand G. CERUTTI,Vacuum, 16, No. 7 (1966), p. 373. Variations in the electrical resistance of thin films heated in air with time and temperature were examined. The films were prepared by evaporating a chromiumsilicon powder. Tests carried out at high temperatures showed the influence of various substrates on the film resistance values at which inversion of the sign of the temperature coefficient of resistance (TCR) occurs. The results showed that films on substrates of silica glass and mica continue to be conductors at temperatures approaching 300°C whilst those on substrates of SAP (synterized aluminium powder) can sometimes go beyond such limits and in some cases reach 500°C. Properties and structure of thin silicon films sputtered on fused quartz substrates. H. Y. KUMAGAI,J. M. THOMPSON and G. KRAUSS, Trans. Metall. Soc. AIME, 236, March (1966), p. 295. Boron-doped p-type and arsenic-doped n-type source materials were used to deposit thin silicon films