Sputtering target for insulating oxide film, method for forming insulating oxide film, and method for producing field-effect transistor
AssigneeRicoh Company, Ltd.
InventorsYukiko Abe, Yuki Nakamura, Shinji Matsumoto, Yuji Sone, Naoyuki Ueda, Ryoichi Saotome, Minehide Kusayanagi
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Abstract
A sputtering target for an insulating oxide film, the sputtering target including a sintered body including a lanthanum oxide and at least one selected from the group consisting of a beryllium oxide, a magnesium oxide, a calcium oxide, a strontium oxide, and a barium oxide, wherein lanthanum has highest molar ratio among elements other than oxygen contained in the sintered body.
Claims4
A field-effect transistor including a gate insulating film formed of an insulating metal oxide film through a sputtering method using a sputtering target for the insulating oxide film, the sputtering target comprising
- a sintered body including a lanthanum oxide and at least one selected from the group consisting of a beryllium oxide, a magnesium oxide, a calcium oxide, a strontium oxide, and a barium oxide,
- wherein lanthanum has highest molar ratio among elements other than oxygen contained in the sintered body of the sputtering target for the insulating oxide film, and
- the insulating metal oxide film is formed by disposing the sputtering target for the insulating metal oxide film in a vacuum chamber, introducing, into the vacuum chamber, sputtering gas that includes oxygen and argon and satisfies an oxygen flow ratio of 0%<O2/(Ar+O2)<90, and sputtering the sputtering target for the insulating metal oxide film with plasma of the sputtering gas.
Dependencies are inferred from the claim text.