GB1411566A - Dielectric body and discharge panel - Google Patents

Abstract

1411566 Coated dielectric layers OWENSILLINOIS INC 17 July 1972 [15 July 1971] 10429/75 Divided out of 1411565 Heading B2E [Also in Division H1] A dielectric surface is coated with a first layer selected from (i) at least one compound of an element of group IA, groups IIA, Al, Si, Ti, Zr, Hf or mixtures thereof or (ii) a conductive or semi-conductive compound of an element of group IB, IIIB, VB or VIII in the form of an isolated island at each discharge site, a second layer selected from the same compounds defined for the first layer and being chemically different from the first layer and a third layer of an electron-emissive material with the proviso that at least one of the layers is selected from (ii) the combinations of the first and second layers being sufficient to prevent ion migration from the dielectric to the third layer and sufficient to provide a thermally and structurally stable base for the third layer and the second layer being chemically inert relative to the third layer. The thickness of each layer may be at least 100Š, preferably 200-10000Š. Compounds useful in the first and second layers include oxides, nitrides, fluorides, borides and carbides of the group IA elements, the group IIA elements, Al, Si, Ti, Zr, Hf or mixtures thereof. Preferred conductive or semicondutive materials are GaAs, GaP, InAs, InSb, InP, Nio, AgOCs - and AuOCs. At least one layer may be lead oxide and/or magnesium oxide. Each of the three layers may be applied vapour deposition, vacuum deposition, chemical vapour deposition, wet spraying and drying, dry spraying, electron beam evaporation, plasma flame and/ or arc spraying and/or deposition and sputtering target techniques.