Method for manufacturing SOI wafer
AssigneeShin-Etsu Handotai Co., Ltd.
InventorIsao Yokokawa
Life of this patent
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Abstract
A method for manufacturing an SOI wafer, including steps of: bonding a bond wafer and a base wafer each composed of a silicon wafer at room temperature with a silicon oxide film interposed therebetween; a thinning the bond wafer; and before the bonding step, cleaning the wafers with a hydrophilic cleaning liquid and drying the cleaned wafers by suction drying or spin drying. After the drying step is ended and before the bonding step is started, the wafers are stored until a state where a bonding speed at which the bonding step is to be performed is 20 mm/second or less. The bonding is performed with the bonding speed of 20 mm/second or less. This provides a method for manufacturing an SOI wafer by which an SOI wafer can be manufactured while generation of outer-peripheral micro voids is suppressed in a simple manner.
Claims10
A method for manufacturing an SOI wafer, the method comprising:
- a bonding step of bonding a bond wafer composed of a silicon wafer and a base wafer composed of a silicon wafer at room temperature with a silicon oxide film interposed therebetween, the silicon oxide film being formed on a surface of at least one of the bond wafer and the base wafer;
- and
- a thinning step of thinning the bond wafer after the bonding step to manufacture an SOI wafer,
- wherein the method further comprises, before the bonding step:
- a cleaning step of cleaning the bond wafer and the base wafer with a hydrophilic cleaning liquid;
- and
- a drying step of drying the cleaned bond wafer and base wafer by at least any one drying method of suction drying and spin drying,
- after the drying step is ended and before the bonding step is started, the bond wafer and the base wafer are stored for a period of 50 minutes or more and 5 hours or less until a state where a bonding speed at which the bonding step is to be performed is 20 mm/second or less, and
- the bonding is performed with the bonding speed of 14 mm/second or more and 20 mm/second or less.
Dependencies are inferred from the claim text.