Pulsed ultra-high aspect ratio dielectric etch
AssigneeLam Research Corporation
InventorsKyeong-Koo Chi, Erik A. Edelberg
Life of this patent
Estimating the term…
Abstract
A method for selectively etching an ultra high aspect ratio feature dielectric layer through a carbon based mask in an etch chamber is provided. A flow of an etch gas is provided, comprising a fluorocarbon containing molecule and an oxygen containing molecule to the etch chamber. A pulsed bias RF signal is provided. An energizing RF signal is provided to transform the etch gas to a plasma.
Claims18
A method for etching an ultra high aspect ratio feature dielectric layer through a carbon based mask in an etch chamber, comprising:
- a selective etching the dielectric layer with respect to the carbon based mask, wherein the selective etching provides a net deposition of a fluorocarbon based polymer on the carbon based mask;
- stopping the selective etch;
- and
- a subsequent selective etching the dielectric layer with respect to the carbon based mask, comprising:
- providing a flow of an etch gas, comprising a fluorocarbon containing molecule and an oxygen containing molecule to the etch chamber;
- providing a pulsed bias RF signal;
- and
- providing an energizing RF signal.
A method for selectively etching an ultra high aspect ratio feature dielectric layer through a carbon based mask in an etch chamber, comprising:
- providing a flow of an etch gas, comprising a fluorocarbon containing molecule and an oxygen containing molecule to the etch chamber;
- providing a pulsed bias RF signal;
- providing an energizing RF signal to transform the etch gas to a plasma;
- and etching the carbon based mask until a feature has a high aspect ratio greater than 25.
Dependencies are inferred from the claim text.