Patent ID: 6835277
Filing Date: 2004-12-28
Classification: H01J

Abstract:
An ashing apparatus for semiconductor wafers, comprising:a reaction chamber; a wafer stage disposed in a lower portion of the chamber so as to support a wafer thereon; a plasma generator that generates plasma ions; an ion ejector, coupled to the plasma generator and extending through a side wall of the reaction chamber, through which the plasma ions are ejected into the reaction chamber; a chamber upper cover transparent to halogen light so that light radiated from a halogen lamp can be transmitted therethrough; and an annular distribution pipe coupled to the ion ejector and disposed within the reaction chamber above said wafer stage, the distribution pipe having a lowermost portion facing in a downward direction towards the wafer stage, a radially innermost portion circumscribing an open area through which light can be transmitted through said cover and onto a wafer supported on the wafer stage, and a plurality of ejection holes extending radially therethrough at locations between said lowermost and radially innermost portions thereof, some of said ejection holes being spaced from each other in a direction along the length of said annular distribution pipe, and some of said ejection holes being spaced from each other in the circumferential direction of the cross section of said pipe, wherein said ejection holes are open directly to the interior of said reaction chamber, and are oriented at such different angles that plasma ions fed into said pipe from said plasma generator are sprayed through the holes directly toward and uniformly onto a wafer supported on the wafer stage.