Sputtering target and method for manufacturing semiconductor device
AssigneeSemiconductor Energy Laboratory Co., Ltd.
InventorShunpei Yamazaki
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Abstract
An object is to provide a deposition technique for depositing an oxide semiconductor film. Another object is to provide a method for manufacturing a highly reliable semiconductor element using the oxide semiconductor film. A novel sputtering target obtained by removing an alkali metal, an alkaline earth metal, and hydrogen that are impurities in a sputtering target used for deposition is used, whereby an oxide semiconductor film containing a small amount of those impurities can be deposited.
Claims16
A sputtering target for forming an oxide semiconductor film, comprising a sintered body of at least one oxide selected from zinc oxide, aluminum oxide, gallium oxide, indium oxide, and tin oxide, wherein concentration of each of alkali metals contained in the sintered body by SIMS is 5×1016 cm−3 or lower.
A method for manufacturing a semiconductor device, the method comprising the steps of:
- forming a conductive film over a substrate;
- etching the conductive film to form a gate electrode;
- forming a gate insulating layer over the gate electrode;
- and
- forming an oxide semiconductor film over the gate insulating layer by a sputtering method using a sputtering target,
- wherein the sputtering target comprises a sintered body of at least one oxide selected from zinc oxide, aluminum oxide, gallium oxide, indium oxide, and tin oxide, wherein concentration of each of alkali metals contained in the sintered body by SIMS is 5×1016 cm−3 or lower.
Dependencies are inferred from the claim text.