Silicon wafer and method for producing the same
AssigneeSiltronic AG
InventorsKatsuhiko Nakai, Atsushi Ikari, Masamichi Ohkubo
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Abstract
Silicon wafers having excellent voltage resistance characteristics of an oxide film and high C-mode characteristics are derived from single crystal silicon ingots doped with nitrogen and hydrogen, characterized in that a plurality of voids constituting a bubble-like void aggregates are present ≧50% relative to total voids; a V1 region having a void density of over 2×104/cm3 and below 1×105/cm3 is ≦20% of the total area of wafer; a V2 region having a void density of 5×102 to 2×104/cm3 occupies ≧80% of the total area of the wafer; and bulk microdefect density is ≧5×108/cm3.
Claims3
A silicon wafer doped with nitrogen and hydrogen, comprising:
- a plurality of voids constituting bubble-like void aggregates which are present in an amount ≧ to 50% of total void number;
- a V1 region having a void density of over 2×104/cm3 and below 1×105/cm3 which occupies ≦ to 20% of the total area of the silicon wafer;
- a V2 region having a void density of 5×102 to 2×104/cm3 which occupies to 80% of the total area of the silicon wafer;
- and
- a bulk micro defect density ≧5×108/cm3.
Dependencies are inferred from the claim text.