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Large single crystals (many cubic centimeters) can be grown by the gas transport (vapor-phase deposition), hydrothermal synthesis, Thin films can be produced by chemical vapor deposition, metalorganic vapour phase epitaxy, electrodeposition, pulsed laser deposition, sputtering, sol-gel synthesis, atomic layer deposition, spray pyrolysis, etc.
Ordinary white powdered zinc oxide can be produced in the laboratory by electrolyzing a solution of sodium bicarbonate with a zinc anode. The zinc hydroxide upon heating decomposes to zinc oxide.
Zn O forms cement-like products when mixed with a strong aqueous solution of zinc chloride and these are best described as zinc hydroxy chlorides.
Zn O decomposes into zinc vapor and oxygen at around 1975 °C with a standard oxygen pressure.
However, many of these form deep acceptors and do not produce significant p-type conduction at room temperature.
In the indirect or French process, metallic zinc is melted in a graphite crucible and vaporized at temperatures above 907 °C (typically around 1000 °C).
Zinc oxide is an inorganic compound with the formula Zn O.
Because of the lower purity of the source material, the final product is also of lower quality in the direct process as compared to the indirect one.Current limitations to p-doping limit electronic and optoelectronic applications of Zn O, which usually require junctions of n-type and p-type material.Known p-type dopants include group-I elements Li, Na, K; group-V elements N, P and As; as well as copper and silver.By weight, most of the world's zinc oxide is manufactured via French process.The direct or American process starts with diverse contaminated zinc composites, such as zinc ores or smelter by-products.