| 摘要 |
A method and apparatus are provided for plasma etching a substrate in a processing chamber. A focus ring assembly circumscribes a substrate support, providing uniform processing conditions near the edge of the substrate. The focus ring assembly comprises two rings, a first ring and a second ring, the first ring comprising quartz, and the second ring comprising monocrystalline silicon, silicon carbide, silicon nitride, silicon oxycarbide, silicon oxynitride, or combinations thereof. The second ring is disposed above the first ring near the edge of the substrate, and creates a uniform electric field and gas composition above the edge of the substrate that results in uniform etching across the substrate surface. |
