Gas distribution apparatus for semiconductor processing

Abstract

A gas distribution system for semiconductor processing that includes a contoured surface to achieve the desired gas distribution on the backside of a shower head. The system may include one or more openings towards the air source between the baffle and the temperature-controlled support member. The baffles can have non-uniform thickness and geometrically controlled openings to achieve the desired gas distribution. In one arrangement the baffle is tapered, with holes of uniform diameter extending at different distances across the baffle to achieve uniform gas pressure through the outlets in the flat bottom surface of the baffle. In another arrangement, the holes have a diameter that gradually increases away from the centrally located gas source outlet. The shape of the baffles and / or the configuration of the holes can be designed to achieve the desired air pressure distribution.

Description

field of invention [0001] This invention relates to reaction chambers for processing semiconductor substrates, such as integrated circuit wafers, and in particular to improvements in gas distribution systems for use in these reaction chambers. Background of the invention [0002] Semiconductor processing includes deposition processes like chemical vapor deposition (CVD) of metal, dielectric, and semiconductor materials, etching of these layers, polishing of photoresist mask layers, and the like. In the case of etching, plasma etching is commonly used to etch metal, dielectric and semiconductor materials. A parallel-plate plasma reactor typically includes a gas chamber containing one or more baffles, a showerhead electrode through which etching gas is passed, a support for supporting the silicon wafer on the bottom electrode, an RF power supply, and Gas injection source for supplying gas to the gas chamber. The gas is ionized by the electrodes to form a plasma. The plasma ...

AI Technical Summary

Problems solved by technology

[0007] According to the foregoing, it can be seen that as the size of the semiconductor substrate increases, it becomes more difficult to achieve a uniform distribution of processing gases on the substrate.

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