Silicon wafer having plasma CVD gettering layer with components/composition changing in depth-wise direction and method of manufacturing the silicon wafer
AssigneeShin-Etsu Handotai Co., Ltd.
InventorsShoichi Takamizawa, Norihiro Kobayashi
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Abstract
In a silicon wafer having a CVD film formed on one main face and having the other main face mirror-polished, the components and/or composition of the CVD film change in the thicknesswise direction of the film. This makes it possible to provide a silicon wafer having a thin film provided on the back surface, which thin film has excellent and persistent gettering capability that can remove a greater variety of types of elements and can prevent autodoping.
Claims20
A silicon wafer having a CVD film formed on one main face and having the other main face mirror-polished, wherein the composition of at least a partial portion of the CVD film continuously changes in the thicknesswise direction of the CVD film.
A method of manufacturing a silicon wafer, comprising the steps of:
- forming a CVD film on one main face of the silicon wafer by chemical vapor deposition in one process step or in a consecutive manner such that the composition of at least a partial portion of the CVD film continuously changes in the thicknesswise direction of the CVD film,
- wherein the silicon wafer has a mirror-polished face on the other main face.
Dependencies are inferred from the claim text.