Method for manufacturing a semiconductor wafer
AssigneeSpeedfam Corporation
InventorMichihiko Yanagisawa
Life of this patent
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Abstract
In the semiconductor wafer manufacturing method of the present invention, a deteriorated layer on the surface of a semiconductor wafer which has been made flat by lapping or polishing is removed by the following dry etching. Plasma which contains a neutral active species is generated within a discharge tube. The neutral active species is separated from the plasma thus generated and is then conveyed to an orifice side of a nozzle portion of the discharge tube. The orifice is opposed to the wafer surface and the nozzle portion moves along the wafer surface while the neutral active species is sprayed from the nozzle orifice toward the wafer surface which is pre-heated. By such dry etching, the deteriorated layer on the wafer surface is removed without the occurrence of any etch pit.
Claims5
A method for manufacturing a semiconductor wafer, comprising:
- a slicing process for slicing an ingot of a single silicon crystal to afford a semiconductor wafer for semiconductors;
- a planarizing process for lapping or polishing a surface of said wafer obtained in the slicing process to flatten the wafer surface;
- a dry etching process for removing a deteriorated layer from said wafer by spraying a neutral active species gas locally to the surface of said wafer obtained in said planarizing process,
- wherein the dry etching process comprises:
- a plasma generating step for allowing a halogen-containing compound gas in a discharge tube to generate plasma gas containing a neutral active species;
- an active species conveying step for separating said neutral active species from said plasma gas by conveying said plasma gas to an orifice side of a nozzle portion of said discharge tube, and spraying the neutral active species locally to the wafer surface opposed to nozzle orifice;
- and
- a deteriorated layer removing step by moving said nozzle portion relatively along said wafer surface to etch off said deteriorated layer from said wafer.
Dependencies are inferred from the claim text.