| 摘要 |
Formation of a metallic interconnect pattern in submicron geometry architectures, without the photoresist being lifted off the substrate and resulting in the deposited metal being electroplated therebeneath, is achieved by a combination of a toughened-skin photoresist and pulsed electroplating. For toughening the skin of the photoresist and thereby enhancing its ability to withstand encroachment of the electrodeposited metal, the photoresist layer is illuminated with ultraviolet radiation. After the UV-irradiated photoresist has been allowed to cool, the resulting structure is placed in an electroplating bath, with appropriate electrodes disposed in the bath and connected to a said layer on the wafer for the deposition of the interconnect metal. The electrode differential is pulsed to provide a low frequency plating current through which the conductor metal is plated onto the seed metal on the wafer, as defined by the pattern of the toughened photoresist. After a prescribed, controlled electrodeposition interval during which the interconnect conductor has been plated to a desired level by the pulsed electroplating current, the wafer is removed from the bath and the photoresist layer is etched off, to leave only the electrodeposited interconnect layer and the underlying base (seed) metal. The exposed base metal is then etched leaving only the desired electrodeposited interconnect pattern.
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