Abstract: Group III-V, II-VI and related monocrystalline compounds are grown with a rigid support of a sealed ampoule, carbon doping and resistivity control, and thermal gradient control in a crystal growth furnace. A support cylinder provides structural support for the combined sealed ampoule crucible assembly, while low-density insulating material inside the support cylinder deters convection and conduction heating. Radiation channels penetrating the low-density material provide pathways for radiation heating into and out of the seed well and transition regions of the crystal growth crucible. A hollow core in the insulation material directly beneath the seed well provides cooling in the center of the growing crystal, which enables uniform, level growth of the crystal ingot and a flat crystal-melt interface which results in crystal wafers with uniform electrical properties.

Abstract: Disclosed is anew technique for measuring the resistivity of ultra-thin carbon films (less than 200 Å). The technique involves using a probe with very smooth surface, a thin layer lubricant (20-30Å)that enables the intimate and stable electrical contact between probe and the thin film, and measurement of I-V curve to determine resistance. Resistivity measurements were conducted on carbon films doped with hydrogen and nitrogen at different mixture ratios and different thicknesses, and the results were compared with those obtained on a commercially available machine that uses a mercury probe. The advantages of the present technique include simple in use, less expensive and quick measurements with reasonably good accuracy.

Abstract: New oxide phosphors based on doped gallium oxides, alkaline earth gallates and germanates for electoluminescent display materials. Bright orange red electroluminescence has been obtained in amorphous and crystalline oxides Ga.sub.2 O.sub.3 :Eu for the first time. SrGa.sub.2 O.sub.4 and SrGa.sub.4 O.sub.9 doped with 1-8 mole % of Eu and Tb, CaGa.sub.2 O.sub.4, Ca.sub.3 Ga.sub.2 O.sub.8 and CaGa.sub.4 O.sub.7 doped with 1-4 mole % of Eu, Tb, Pr and Dy, BaGa.sub.2 O.sub.4 doped with 1-2 mole % of Eu and Tb, have been prepared using RF magnetron sputtering onto ceramic dielectric substrates and annealed at 600.degree. C.-950.degree. C. in air or Ar for 1-2 hours. Bright electroluminescent (EL) emission was obtained with wavelengths covering the visible spectrum from 400 to 700 nm, and infrared emission above 700 nm with spectral peaks characteristic of rare earth transitions. The films of CaGa.sub.2 O.sub.4 with 1 mole % Eu achieved 22 fL (75 cd/m.sup.2) at 60 Hz and had a maximum efficiency of 0.

Abstract: New oxide phosphors based on doped gallium oxides, alkaline earth gallates and germanates for electroluminescent display materials. Bright orange red electroluminescence has been obtained in amorphous and crystalline oxides Ga.sub.2 O.sub.3 :Eu for the first time. SrGa.sub.2 O.sub.4 and SrGa.sub.4 O.sub.9 doped with 1-8 mole % of Eu and Tb, CaGa.sub.2 O.sub.4, Ca.sub.3 Ga.sub.2 O.sub.6 and CaGa.sub.4 O.sub.7 doped with 1-4 mole % of Eu, Tb, Pr and Dy, BaGa.sub.2 O.sub.4 doped with 1-2 mole % of Eu and Tb, have been prepared using RF magnetron sputtering onto ceramic dielectric substrates and annealed at 600.degree. C.-950.degree. C. in air or Ar for 1-2 hours. Bright electroluminescent (EL) emission was obtained with wavelengths covering the visible spectrum from 400 to 700 nm, and infrared emission above 700 nm with spectral peaks characteristic of rare earth transitions. The films of CaGa.sub.2 O.sub.4 with 1 mole % Eu achieved 22 fL (75 cd/m.sup.2) at 60 Hz and had a maximum efficiency of 0.

Abstract: Improved electrochemical sensors are provided through isostatic processing techniques. Improved electrochemical sensors, especially those suitable for use in metallurgical melts, having, at once, long-term stability, improved sensitivity, and improved physical properties including thermal shock resistance are provided. In accordance with a preferred embodiment, unitary bodies comprising the sensing electrolyte and a source of reference potential are fabricated through isostatic processing techniques. Methods for the preparation of these improved sensors together with methods for the improvement of sensing, especially of oxygen in metallurgical melts are also disclosed.

Abstract: Improved electrochemical sensors are provided through isostatic processing techniques. Improved electrochemical sensors, especially those suitable for use in metallurgical melts, having, at once, long-term stability, improved sensitivity, and improved physical properties including thermal shock resistance are provided. In accordance with a preferred embodiment, unitary bodies comprising the sensing electrolyte and a source of reference potential are fabricated through isostatic processing techniques. Methods for the preparation of these improved sensors together with methods for the improvement of sensing, especially of oxygen in metallurgical melts are also disclosed.

Abstract: An improved gaseous sulfur dioxide galvanic cell is formed by utilizing a solid electrolyte composed of a mixture of lithium sulfate and silver sulfate. A reference electrode is formed by placing a solid mixture of the electrolyte mixture and metallic silver in contact with a portion of the surface of the solid electrolyte. A gas-type detector electrode is provided by contacting the solid electrolyte with a gold lead at a point spatially separated from the contact point between the reference electrode and electrolyte. Catalyst means are preferably provided to convert the sulfur dioxide to an equilibrium mixture of sulfur dioxide and sulfur trioxide near the electrolyte detector electrode surface. The electrolyte is preferably heated to a temperature at which it is a two-phased mixture of solid solutions for increased long term stability.

Abstract: Materials, methods and articles for the electrochemical determination of sulfur and carbon in fluids are provided. In accordance with a preferred embodiment, an electrolyte is furnished comprising a solid solution of an oxide of either zirconium, thorium or hafnium together with an oxide of an element of groups IIA or IIIB of the periodic table of the elements together with a sulfide or carbide of an element of groups IIA or IIIB of the periodic table. Processes employing such electrolytes together with articles incorporating them are also contemplated.