Internal plasma grids for semiconductor manufacturing

Abstract

Embodiments disclosed herein relate to internal plasma grids for semiconductor manufacturing, and in particular to improved methods and apparatus for etching semiconductor substrates. A plasma grid is positioned in the reaction chamber to divide the chamber into upper and lower sub-chambers. The plasma grid may have specific aspect ratio slots to allow certain species to pass from the upper subchamber to the lower subchamber. In some cases, an electron-ion plasma is generated in the upper subchamber. Electrons passing through the grid to the lower subchamber are cooled as they pass. In some cases, this results in an ion-ion plasma in the lower subchamber. The plasma in the lower subchamber has a lower electron density, lower electron effective temperature and higher negative ion:positive ion ratio than the plasma in the upper subchamber. The disclosed embodiments may result in an etch process with good center-to-edge uniformity, selectivity, profile angle, and Iso / dense loading.

Description

[0001] Cross References to Related Applications [0002] This application claims priority to U.S. Patent Application No. 14 / 082,009, filed June 12, 2013, entitled "INTERNAL PLASMA GRID FORSEMICONDUCTOR FABRICATION," which claims priority on April 5, 2013 Priority to U.S. Provisional Application No. 61 / 809,246, entitled "INTERNAL PLASMA GRID FORSEMICONDUCTOR FABRICATION," filed on , each of which is hereby incorporated by reference in its entirety for all purposes. technical field [0003] The present invention relates generally to the field of semiconductor fabrication technology, and more particularly to internal plasma grids for semiconductor fabrication. Background technique [0004] One operation frequently employed in semiconductor production is an etching operation. In an etching operation, one or more materials are partially or completely removed from a partially fabricated integrated circuit. Plasma etching is frequently used, especially where the geometries involv...

AI Technical Summary

Problems solved by technology

[0008] Multiple objectives such as those articulated above have been found to be difficult to achieve when etching advanced structures such as FinFET gates

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