Sputtering target and method of manufacturing the same
AssigneeKabushiki Kaisha Toshiba
InventorsMichio Satou, Takasi Yamanobe, Mituo Kawai, Tooru Komatu, Hiromi Shizu, Noriaki Yagi
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Abstract
According to the present invention, silicide grains are coupled with each other in a linked manner so as to provide a metal silicide phase, and grains forming a Si phase are dispersed in the gaps of the metal silicide phase discontinuously so as to provide a mixed structure of a sputtering target of high density and containing carbon at a rate less than 100 ppm. Because of the high density and high strength of the target, generation of particles at the time of sputtering can be reduced, and because of the reduced content of carbon, mixing of carbon in a thin film formed by the sputtering can be prevented.
Claims6
A method of manufacturing a sputtering target comprising a metal silicide of a stoichiometric composition expressed by MSi.sub.2 where M represents a metal coupled in link form so as to provide a metal silicide phase having gaps and a Si phase made of Si grains dispersed in the gaps of the silicide phase discontinuously so as to provide a compact mixed structure of the target, the compact mixed structure having a carbon content of less than 100 ppm, said method comprising:
- I. a step of mixing metal powder M and Si powder Si at a Si/M atom ratio ranging from 2.0 to 4.0 so as to form a mixed powder;
- II. a step of filling the mixed powder obtained in step I in a mold, and heating the mixed powder in a vacuum of less than 10.sup.-4 Torr at a temperature of from 1000.degree. to 1300.degree. C. to reduce carbon and oxygen amounts in the mixed powder;
- III. a step wherein the heated and degassed mixed powder obtained in step II is heated in a vacuum of less than 10.sup.-4 Torr and under a press-pressure of from 10 to 100 Kg/cm.sup.2 to execute synthesis and sintering of the metal silicide;
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- IV. a step where the material obtained in step III. is further heated in a vacuum of less than 10.sup.-4 Torr or an inert gas and under a press-pressure of from 100-300 Kg/cm.sup.2 to a temperature T, wherein T.sub.s -50.ltoreq.T<T.sub.s where T.sub.s is the eutectic temperature in .degree. C., to promote compactness of the target.
Dependencies are inferred from the claim text.