Silicon wafer for hydrogen heat treatment and method for manufacturing the same
AssigneeKomatsu Electronic Metals Co., Ltd.
InventorsToshiaki Saishoji, Kozo Nakamura, Junsuke Tomioka
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Abstract
In growing silicon single crystals by the CZ method, the cooling rate in the 1150-1080° C. temperature zone (defect-forming temperature range) where the grown-in defects are formed is set at more than 2.0° C./min to manufacture single crystals having an as-grown LSTD density of larger than 3.0×106/cm3 or a FPD density of larger than 6.0×105/cm3. As this single crystal has a small defect size, thus the dissolution rate of the defects increases by the heat treatment in a non-oxidizing atmosphere containing a hydrogen gas, so the effect of the hydrogen heat treatment can extend to the depth more than 3 μm from the wafer surface.
Claims3
A method of manufacturing a silicon wafer for a hydrogen heat treatment, comprising the steps of:
- growing a single crystal silicon by the CZ method;
- and
- slicing the single crystal silicon into silicon wafers,
- wherein the step of growing comprises a step of pulling the single crystal silicon while cooling and a cooling rate at a temperature range of 1150° C.-1080° C. is larger than 2.0° C./min in the step of growing.
Dependencies are inferred from the claim text.