PLASMA ETCHING PROCESS
First Claim
1. A method for etching a layer to be etched in a plasma etching reactor, with such method comprising:
- an initial phase comprising;
at least one initial step of etching, with the initial step of etching comprising, for a duration D0, an injection into the reactor of at least one reactive gas to form a reactive gas plasma, with the reactive gas plasma forming, together with the layer to be etched, a reactive layer which goes into the layer to be etched, with the duration D0 of injection being longer than a determined duration Ds of injection upon completion of which the reactive layer reaches a steady state thickness which will be steady over time, so that the thickness of the reactive layer can reach said steady state thickness during said initial step of etching;
at least one step of removing the reactive layer, formed upon completion of the initial step of etching;
with the method comprising, after the initial phase, a subsequent phase including at least a sequence of steps, with each sequence including at least the following steps;
for a duration D1, an injection into the reactor of at least one reactive gas to form a reactive gas plasma, with the reactive gas plasma forming, together with the layer to be etched, a reactive layer which goes into the layer to be etched, with the duration D1 of injection being shorter than the determined duration Ds of injection upon completion of which the reactive layer would reach a steady state thickness, so that, during the subsequent phase, the thickness of the reactive layer remains smaller than said steady state thickness;
at least one step of removing the reactive layer, formed upon completion of the injection performed during the duration D1, with the removing step comprising injecting at least one inert gas into the reactor to form an inert gas plasma making it possible to remove the reactive layer only, formed upon completion of the injection performed during the duration D1.
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Accused Products
Abstract
A method and system are provided for etching a layer to be etched in a plasma etching reactor, including: forming a reactive layer by injection of at least one reactive gas to form a reactive gas plasma, which forms, together with the layer to be etched, a reactive layer which goes into the layer to be etched during etching of said layer to be etched, wherein the reactive layer reaches a steady state thickness upon completion of a determined duration of said injection; said injection being interrupted before said determined duration has elapsed so that, upon completion of the forming of the reactive layer, the thickness of the reactive layer is smaller than said steady state thickness; and removing the reactive layer by injection of at least one inert gas to form an inert gas plasma, which makes it possible to remove only the reactive layer.
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Citations
27 Claims
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1. A method for etching a layer to be etched in a plasma etching reactor, with such method comprising:
an initial phase comprising; at least one initial step of etching, with the initial step of etching comprising, for a duration D0, an injection into the reactor of at least one reactive gas to form a reactive gas plasma, with the reactive gas plasma forming, together with the layer to be etched, a reactive layer which goes into the layer to be etched, with the duration D0 of injection being longer than a determined duration Ds of injection upon completion of which the reactive layer reaches a steady state thickness which will be steady over time, so that the thickness of the reactive layer can reach said steady state thickness during said initial step of etching; at least one step of removing the reactive layer, formed upon completion of the initial step of etching; with the method comprising, after the initial phase, a subsequent phase including at least a sequence of steps, with each sequence including at least the following steps; for a duration D1, an injection into the reactor of at least one reactive gas to form a reactive gas plasma, with the reactive gas plasma forming, together with the layer to be etched, a reactive layer which goes into the layer to be etched, with the duration D1 of injection being shorter than the determined duration Ds of injection upon completion of which the reactive layer would reach a steady state thickness, so that, during the subsequent phase, the thickness of the reactive layer remains smaller than said steady state thickness; at least one step of removing the reactive layer, formed upon completion of the injection performed during the duration D1, with the removing step comprising injecting at least one inert gas into the reactor to form an inert gas plasma making it possible to remove the reactive layer only, formed upon completion of the injection performed during the duration D1. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 27)
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26. A method for etching a layer to be etched in a plasma etching reactor, with such method comprising at least:
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a step of forming a reactive layer comprising an injection of at least one reactive gas into the reactor to form a reactive gas plasma able to etch the layer to be etched, with a reactive layer being formed on the surface of the layer to be etched under the effect of the reactive gas plasma, characterized in that; the injection of the reactive gas is executed for a duration D1 shorter than 1,000 milliseconds, and in that; the method comprises at least one step of removing the reactive layer, at least partly executed after the step of forming the reactive layer, with the removing step comprising injecting at least one inert gas into the reactor to form an inert gas plasma making it possible to remove the reactive layer; and comprising the following step executed prior to the step of forming a reactive layer by injecting the reactive gas for a duration D1; one initial step of etching, for a duration D0, an injection into the reactor of at least one reactive gas to form a reactive gas plasma, with the reactive gas plasma forming, together with the layer to be etched, a reactive layer which goes into the layer to be etched, with the duration D0 of injection being longer than a determined duration Ds of injection, upon completion of which the reactive layer reaches a steady state thickness, so that the thickness of the reactive layer can reach said steady state thickness during said initial step of etching.
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Specification