Silicon oxide selective dry etch process

Abstract

Systems and methods for processing a workpiece are provided. In one example, a method includes exposing the workpiece to a first gas mixture when the workpiece is at a first temperature to conduct a doped silicate glass etch process. The first gas mixture can include hydrofluoric acid (HF) vapor. The doped silicate glass etch process at least partially removes the doped silicate glass layer at a first etch rate that is greater than a second etch rate associated with removal of the at least one second layer. The method can include heating the workpiece to a second temperature. The second temperature is greater than the first temperature. The method can include exposing the workpiece to a second gas mixture when the workpiece is at a second temperature to remove a residue from the workpiece.

Description

[0001] priority statement [0002] This application claims priority to US Application Serial No. 16 / 557,346, filed August 30, 2019, entitled "Silicon Oxide Selective Dry Etch Process," which is incorporated by reference. technical field [0003] The present disclosure generally relates to the processing of workpieces, such as semiconductor workpieces. Background technique [0004] Processing of semiconductor workpieces can involve depositing, patterning, and removing layers of different materials on a substrate to form multilayer structures. For better patterning contrast in the fabrication of 3D device structures, each layer is approximately planar. Within each layer, a dielectric material such as silicate glass can be used to separate structures and insulate conductive materials. Doped silicate glasses, including borosilicate glass (BSG), phosphosilicate glass (PSG) and borophosphosilicate glass (BPSG), are commonly used as dielectric or insulating layers between conduct...

AI Technical Summary

Problems solved by technology

Finally, as mentioned above, wet etch processes can have issues with surface tension induced pattern collapse and post-etch residue inside high aspect ratio structures

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