Self-aligned double patterning with spatial atomic layer deposition
Provided are self-aligned double patterning methods including feature trimming. The SADP process is performed in a single batch processing chamber in which the substrate is laterally moved between sections of the processing chamber separated by gas curtains so that each section independently has a process condition.
1. A processing method for self-aligned double patterning, the processing method comprising:
exposing a patterned layer of a substrate to a plasma, the substrate having a first layer and the patterned layer thereon, portions of the first layer exposed through the patterned layer, the patterned layer comprising a feature having a top surface and two vertical faces defining an initial width prior to exposing the patterned layer to the plasma and with an aspect ratio greater than about 3:1, the two vertical faces substantially perpendicular to the first layer;
reducing the initial width of the patterned layer by an amount greater than or equal to about 30% of the initial width of a feature;
depositing a substantially conformal spacer layer over the first layer and patterned layer by radical assisted ALD with a direct plasma and an ion blocker at a temperature less than 100° C., the ion blocker filtering out ionic components from the direct plasma, so that the substantially conformal spacer layer forms a film on the portions of the first layer exposed through the patterned layer, the top surface and both vertical faces of the feature; and
etching the substantially conformal spacer layer from the top surface of the feature and the portions of the first layer exposed through the patterned layer,
wherein each of exposing the pattern layer to the plasma, depositing the substantially conformal spacer layer and the etching the spacer layer occurs in a single processing chamber in which the substrate is moved laterally between a plurality of sections, each section separated from adjacent sections by a gas curtain,
wherein during the substrate being moved laterally:
a first portion of the substrate is exposed to one of the exposing the patterned layer, reducing the initial width of the patterned layer, depositing the substantially conformal spacer layer, or etching the conformal spacer layer,
at the same time that a second portion of the substrate is exposed to a different one of the exposing the patterned layer, reducing the initial width of the patterned layer, depositing the substantially conformal spacer layer, or etching the conformal spacer layer, and
at the same time that an intermediate portion of the substrate is exposed to the gas curtain.
2. The processing method of claim 1 , wherein the patterned layer comprises one or more of a photoresist or spin-on-carbon.
3. The processing method of claim 1 , wherein the patterned layer has an initial width in the range of about 200 Å to about 800 Å.
4. The processing method of claim 1 , wherein the patterned layer comprises a dielectric.
5. The processing method of claim 1 , wherein the patterned layer has an aspect ratio in the range of about 3:1 to about 20:1.
6. The processing method of claim 1 , wherein the patterned layer comprises spin-on-carbon.
7. The processing method of claim 1 , the initial width is reduced by an amount in the range of about 10 Å to about 200 Å.
8. The processing method of claim 1 , wherein after exposing the patterned layer to the plasma, the vertical faces are substantially perpendicular to the first layer.
9. The processing method of claim 1 , wherein the spacer layer comprises one or more of an oxide, a nitride or a carbonitride.
10. The method of claim 1 , further comprising removing the patterned layer followed by etching the spacer and exposed first layer.
11. A processing method for self-aligned double patterning, the processing method comprising:
exposing at least a portion of a substrate with a first layer and a patterned layer thereon to a first process condition in a first section of a processing chamber and exposing portions of the first layer through the patterned layer, the patterned layer comprising a feature having a top surface and two vertical faces defining an initial width prior to exposing the at least the portion of the substrate to the first process condition, the feature having an aspect ratio greater than or equal to about 3:1, the two vertical faces substantially perpendicular to the first layer, the first process condition comprising a plasma;
trimming the patterned layer and reducing the initial width by greater than or equal to about 40% of the initial width;
laterally moving the substrate through a gas curtain comprising a purge gas stream and a vacuum stream to a second section of the processing chamber;
exposing the substrate to radical assisted ALD with a direct plasma and an ion blocker at a temperature less than 100° C., the ion blocker filtering out ionic components from the direct plasma, to deposit a substantially conformal spacer layer over the first layer and the patterned layer so that the substantially conformal spacer layer forms a film on the portions of the first layer exposed through the patterned layer, the top surface and both vertical faces of the feature;
laterally moving the substrate through a gas curtain comprising a purge gas stream and a vacuum stream to a third section of the processing chamber; and
exposing the substrate to a third process condition to etch the substantially conformal spacer layer from the top surface of the at least one feature and the portions of the first layer exposed through the patterned layer,
wherein during lateral movement of the substrate, a first portion of the substrate is exposed to the first process condition at the same time that a second portion of the substrate is exposed to the second process condition and an intermediate portion of the substrate is exposed to the gas curtain.
12. The processing method of claim 11 , wherein the patterned layer has an initial width in the range of about 200 Å to about 800 Å.
13. The processing method of claim 11 , wherein trimming the patterned layer reduced the width by an amount in the range of about 10 Å to about 200 Å.
14. The processing method of claim 11 , wherein the spacer layer comprises one or more of an oxide, a nitride or a carbonitride.
15. The method of claim 11 , further comprising removing the patterned layer followed by etching the spacer and exposed first layer.
16. A processing method for self-aligned double patterning, the processing method comprising:
exposing a substrate layer to a plasma, the substrate having a first layer comprising a dielectric and a patterned layer comprising spin-on-carbon thereon, portions of the first layer exposed through the patterned layer, the patterned layer comprising a feature having a top surface and two vertical faces defining an initial width in the range of about 200 Å to about 800 Å, with an aspect ratio greater than about 3:1, the two vertical faces substantially perpendicular to the first layer, wherein exposing the substrate to the plasma reduces the initial width of the patterned layer by an amount greater than or equal to about 50% of the initial width and the vertical faces remain substantially perpendicular to the first layer; and
depositing a substantially conformal spacer layer comprising a silicide over the first layer and patterned layer by radical assisted ALD with a direct plasma and an ion blocker at a temperature less than 100° C., the ion blocker filtering out ionic components from the direct plasma, so that the substantially conformal spacer layer forms a film on the portions of the first layer exposed through the patterned layer, the top surface and both vertical faces of the feature; and
etching the substantially conformal spacer layer from the top surface of the feature and the portions of the first layer exposed through the patterned layer,
wherein each of exposing the substrate to the plasma, depositing the substantially conformal spacer layer and the etching the spacer layer occurs in a single processing chamber in which the substrate is moved laterally between a plurality of sections, each section separated from adjacent sections by a gas curtain, wherein during the lateral movement a first portion of the substrate is exposed to one of exposing the substrate layer, depositing the substantially conformal spacer layer and etching the substantially conformal spacer layer, at the same time that a second portion of the substrate is exposed to a different one of exposing the substrate layer, depositing the substantially conformal spacer layer, or etching the substantially conformal spacer layer, and an intermediate portion of the substrate is exposed to the gas curtain.