Patent ID: 7484546
Filing Date: 2009-02-03
Classification: C23C,G11B,H01L

Abstract:
1. A method of manufacturing a sputtering target for use in forming a phase change memory film, comprising the steps of melting and casting a raw material in a vacuum or under a hermetically sealed inert gas atmosphere to form an ingot pulverizing the ingot to form a powder, and hot pressing the powder to form said sputtering target such that the sputtering target is composed from elements of not less than a three component system and one or more principal components selected from a group consisting of stibium, tellurium and selenium, said target has a compositional deviation in relation to an intended composition of ±1.0 at % or less, an average crystal grain size of 50 μm or less and a relative density of 90% or more; said target having a purity, excluding gas components, of 99.995 wt. % or more, and a total amount of carbon, nitrogen, oxygen and sulfur, which are gas components, of 700 ppm or less and said target has an average value of composition Ai (wt %) of respective constituent elements of said target, excluding the one or more principal components, in each of two or more samples (i =2, 3, 4 . . . ) collected from an arbitrary location within said target of A(wt %), |A−Ai|≦0.15.