Silicon-based deposition for semiconductor processing

Patent metadata

Field	Value
Publication number	US-10600648-B2
Application number	US-201715492662-A
Country	US
Kind code	B2
Filing date	Apr 20, 2017
Priority date	Apr 20, 2017
Publication date	Mar 24, 2020
Grant date	Mar 24, 2020

Abstract

A method for processing a stack with a carbon based patterned mask is provided. The stack is placed in an etch chamber. A silicon oxide layer is deposited by atomic layer deposition over the carbon based patterned mask by providing a plurality of cycles, wherein each of the cycles of the plurality of cycles, comprises providing a silicon precursor deposition phase, comprising flowing an atomic layer deposition precursor gas into the etch chamber, where the atomic layer deposition precursor gas is deposited while plasmaless and stopping the flow of the atomic layer deposition precursor gas and providing an oxygen deposition phase, comprising flowing ozone gas into the etch chamber, wherein the ozone gas binds with the deposited precursor gas while plasmaless and stopping the flow of ozone gas into the etch chamber. Part of the silicon oxide layer is etched. The stack is removed from the etch chamber.

First claim

What is claimed is:

1. A method for processing a stack with a carbon based patterned mask in-situ, comprising:
placing the stack in an etch chamber;
depositing by atomic layer deposition a silicon oxide layer over the carbon based patterned mask without consuming or attacking the carbon based patterned mask by providing a plurality of cycles, wherein each of the plurality of cycles comprises:
providing a silicon precursor deposition phase, comprising:
flowing an atomic layer deposition precursor gas comprising a silicon containing component into the etch chamber, where the atomic layer deposition precursor gas is deposited over the carbon based patterned mask, while plasmaless; and
stopping the flow of the atomic layer deposition precursor gas; and

providing an oxygen deposition phase, comprising:
flowing only an oxygen deposition gas consisting essentially of ozone gas into the etch chamber, wherein the ozone gas binds with the deposited precursor gas, while plasmaless; and
stopping the flow of the oxygen deposition gas into the etch chamber;

etching part of the silicon oxide layer, comprising:
flowing a shaping gas comprising a fluorocarbon into the etch chamber;
forming the shaping gas into a plasma, which etches the silicon oxide layer; and
stopping the flow of the shaping gas; and

removing the stack from the etch chamber.

2. The method, as recited in claim 1 , further comprising trimming the carbon based patterned mask after placing the stack in the etch chamber and before depositing the silicon oxide layer over the carbon based patterned mask.

3. The method, as recited in claim 2 , further comprising:
stripping the carbon based patterned mask after etching the silicon oxide layer; and
etching an etch layer below the silicon oxide layer after stripping the carbon based patterned mask and before removing the stack from the etch chamber.

4. The method, as recited in claim 3 , wherein the carbon based patterned mask comprises at least one of amorphous carbon, organic material, or photoresist.

5. The method, as recited in claim 4 , wherein a BARC layer is below the carbon based patterned mask, further comprising etching the BARC layer before depositing the silicon oxide layer over the carbon based patterned mask.

6. The method, as recited in claim 5 , wherein the silicon containing component of the atomic layer deposition precursor gas is aminosilane BTBAS (bis(tertiarybutylamino)silane) or H 2 Si[N(C 2 H 5 ) 2 ] 2 .

7. The method, as recited in claim 6 , wherein the flowing of the ozone gas into the etch chamber provides a pressure of greater than 100 mTorr.

8. The method, as recited in claim 1 , further comprising:
stripping the carbon based patterned mask after etching the silicon oxide layer; and
etching an etch layer below the silicon oxide layer after stripping the carbon based patterned mask and before removing the stack from the etch chamber.

9. The method, as recited in claim 1 , wherein the carbon based patterned mask comprises at least one of amorphous carbon, organic material, or photoresist.

10. The method, as recited in claim 1 , wherein a BARC layer is below the carbon based patterned mask, further comprising etching the BARC layer before depositing the silicon oxide layer over the carbon based patterned mask.

11. The method, as recited in claim 1 , wherein the silicon containing component of the atomic layer deposition precursor gas is aminosilane BTBAS (bis(tertiarybutylamino)silane) or H 2 Si[N(C 2 H 5 ) 2 ] 2 .

12. The method, as recited in claim 1 , wherein the flowing of the ozone gas into the etch chamber provides a pressure of greater than 100 mTorr.

13. The method, as recited in claim 1 , wherein the carbon based patterned mask comprises photoresist.

14. An apparatus for etching an etch layer in a stack in-situ, wherein the etch layer is below a carbon based patterned mask, comprising a processing chamber;
a substrate support within the processing chamber;
a gas inlet for providing a process gas into the processing chamber;
a gas source for providing the process gas to the gas inlet, wherein the gas source comprises:
an ozone source;
an atomic layer deposition precursor silicon containing gas source; and
a shaping gas source;

an exhaust pump for pumping gas from the processing chamber;
a lower electrode;
an electrode or a coil;
at least one power source for providing power to the lower electrode and the electrode or coil; and
a controller controllably connected to the gas source and the at least one power source, wherein the controller comprises:
at least one processor; and
computer readable media, comprising:
computer readable code for depositing by atomic layer deposition a silicon oxide layer over the carbon based patterned mask by providing a plurality of cycles, wherein each of the plurality of cycles comprises:
providing a silicon precursor deposition phase, comprising:
 flowing an atomic layer deposition precursor gas comprising a silicon containing component into the etch chamber, where the atomic layer deposition precursor gas is deposited over the carbon based patterned mask, while plasmaless; and
 stopping the flow of the atomic layer deposition precursor gas; and
providing an oxygen deposition phase, comprising:
 flowing only an oxygen deposition gas consisting essentially of ozone gas into the etch chamber, wherein the ozone gas binds with the deposited precursor gas, while plasmaless; and
 stopping the flow of the oxygen deposition gas into the etch chamber; and

computer readable code for etching the silicon oxide layer, comprising:
flowing a shaping gas comprising a fluorocarbon into the etch chamber; and
forming the shaping gas into a plasma, which etches the silicon oxide layer.

15. The apparatus, as recited in claim 14 , wherein the gas source, further comprises:
a trim gas source;
a stripping gas source; and
a feature etch gas source.

16. The apparatus, as recited in claim 15 , wherein the computer readable media further comprises:
computer readable code for trimming the carbon based patterned mask before depositing the atomic layer deposition, comprising:
computer readable code for flowing trimming gas from the trimming gas source into the processing chamber;
computer readable code for providing power to the electrode or coil, which transforms the trimming gas into a plasma, causing the trimming of the carbon based patterned mask; and
computer readable code for stopping the flow of the trimming gas; and

computer readable code for stripping the carbon based patterned mask after etching the silicon oxide layer, comprising:
computer readable code for flowing stripping gas from the stripping gas source into the etch chamber;
computer readable code for providing power to the electrode or coil, which transforms the stripping gas into a plasma, causing the stripping of the carbon based mask; and
computer readable code for stopping the flow of the stripping gas; and

computer readable code for etching the etch layer after stripping the carbon based patterned mask, comprising:
computer readable code for flowing a feature etch gas from the feature etch gas source into the processing chamber;
computer readable code for providing power to the electrode or coil, which transforms the feature etch gas into a plasma, causing the etching of the etch layer; and
computer readable code for stopping the flow of the feature etch gas.

17. The apparatus, as recited in claim 16 , wherein the atomic layer deposition precursor silicon containing gas source provide

Assignees

• Lam Res Corp

Inventors

• Kamp Tom A
• Abatchev Mirzafer K

Classifications

• H10P50/287

  by chemical means · CPC title

• H10P50/285

  of materials not containing Si, e.g. PZT or Al2O3 · CPC title

• H10P50/283

  by chemical means · CPC title

• H10P50/268

  of silicon-containing layers · CPC title

• H10P14/69215

  the material being a silicon oxide, e.g. SiO2 · CPC title