A process for the fabrication of a supported iron oxide pattern involves electromagnetic wave irradiation of a blank. The blank consists of a layer of iron oxide which is soluble in, for example, an acid medium. Irradiation results in insolubilization so that delineation is accomplished by immersing the processed blank in a suitable solvent.

Pattern delineation method and product so produced

Amorphous iron oxide is deposited on the surface of a substrate at a temperature within 7% of its crystallization temperature to provide a layer thereof which can be crystallized in 10 milliseconds or less. In a particular embodiment, the amorphous ferric oxide is deposited on a semiconductor surface to provide a mask therefor for subsequent diffusion processing, or the like.

Rapid conversion of an iron oxide film

A four-step cleaning process is used for cleaning substrates, such as glass plates, to allow vacuum deposition of pinhole free films, such as chromium films for the fabrication of chromium masks, on the plates. The plates are first brush scrubbed in an aqueous bath. They are then ultrasonically pulsed in a second aqueous bath. The first and second aqueous baths may contain additives, such as sodium bicarbonate, to enhance the cleaning effect. The plates undergo an overflow rinse in purified water until a predetermined resistivity measurement, such as 8 megohms, is obtained. The plates are then spin dried. In the fabrication of chromium masks, a film of chromium is then vacuum evaporated or sputtered on the plates, followed by selective removal of chromium, such as by a photoresist and etching step, to give a desired image pattern.

Substrate cleaning process

A pattern of transparent conductive material, such as tin oxide, is formed on a transparent vitreous substrate using a polycrystalline material, such as cadmium or zinc sulfide, to mask the substrate surface while depositing material forming the transparent conductive layer. The polycrystalline material and any overlying transparent conductive material are easily removed by a chemical etch, leaving the desired pattern of transparent conductive material adhering to the substrate. Two electrically conductive patterns may be formed in intersecting relationship and isolated, one from the other. The degree of electrical connection between the two patterns will be a function of the resistance of the polycrystalline material therebetween at points of crossing. In some instances, electroluminescence may be obtained by selecting the proper crystalline material wherein an electrical display may be created by selectively energizing crossing electrical conductors.

Process for forming tin oxide conductive pattern

A process for forming a pattern of metal oxide on a substrate wherein a metal oxide is selectively formed or etched in accordance with a thermal pattern. In one embodiment, selected portions of a uniform layer of substantially amorphous metal oxide are converted to a more crystalline form by heat and remaining amorphous oxide portions are removed by chemical etching to form the pattern. In another embodiment, a metal-organic compound precursor of the metal oxide is thermally decomposed on the substrate in accordance with the pattern. A novel vapor etching process, and a novel sputtering process for forming amorphous metal oxide, are disclosed.

Process for forming a metal oxide pattern

A METHOD OF MAKING THIN FILMS OF ALPHA FE2O3 BY APPLYING TO AN UNHEATED SUBSTRATE A FILM OF A HIGHLY PERMEABLE NON-CRYSTALLINE FORM OF IRON OXIDE BY SUBJECTING THE SUBSTRATE TO VAPOR PRODUCED BY EVAPORATING A SOURCE OF IRON OXIDE AT A PRESSURE LESS THAN 10-4 TORR AND THEREAFTER HEATING THE DEPOSITED FILM IN AN OXIDIZING ATMOSPHERE AT A TEMPERATURE OF AT LEAST 425*C. FOR A PERIOD OF TIME SUFFICIENT TO CONVERT IT TO A STABLE, CRYSTALLINE FILM OF HEMATITE, ALPHA FE2O3. A FILM OF HEMATITE SO FORMED HAVING A THICKNESS IN THE RANGE OF 1000 A.-3600 A. ON A SUBSTRATE OF TRANSPARENT, ALKALI-FREE GLASS MAY BE PATTERNED TO FORM A MICROCIRCUIT MASK HAVING INCREASED TRANSMISSION IN THE VISIBLE PORTION OF THE SPECTRUM.

Raymond E Szupillo

Papers

Thin films of alpha fe2o3 and method of forming

Chromium filmed glass articles and method for making the same