Method for high modulus ALD SiO2 spacer
Methods and apparatuses for forming high modulus silicon oxide spacers using atomic layer deposition are provided. Methods involve depositing at high temperature, using high plasma energy, and post-treating deposited silicon oxide using ultraviolet radiation. Such silicon oxide spacers are suitable for use as masks in multiple patterning applications to prevent pitch walking.
1. A method of performing multiple patterning on a substrate, the method comprising:
providing a substrate having a patterned core material;
exposing the substrate to alternating exposures of a silicon-containing precursor and an oxidant; and
igniting a plasma when exposing the substrate to the oxidant to form a conformal silicon oxide spacer material having an elastic modulus of at least 55 GPa over the patterned core material, wherein forming the conformal silicon oxide spacer material is conducted at a substrate temperature greater than about 50° C. and less than about 80° C.
2. The method of claim 1 , wherein the plasma is ignited using a radio frequency plasma energy of at least about 1000 Joules.
3. The method of claim 1 , further comprising exposing the conformal silicon oxide spacer material to ultraviolet radiation to densify the conformal silicon oxide spacer material.
4. The method of claim 3 , wherein the plasma is ignited using a radio frequency plasma energy of at least about 1000 Joules.
5. The method of claim 1 , wherein the plasma is ignited using a radio frequency plasma energy of at least about 1000 Joules.
6. The method of claim 5 , further comprising exposing the conformal silicon oxide spacer material to ultraviolet radiation to densify the conformal silicon oxide spacer material.
7. The method of claim 3 , wherein the conformal silicon oxide spacer material is exposed to the ultraviolet radiation for a duration between about 5 minutes and about 30 minutes.
8. The method of claim 1 , wherein the patterned core material comprises features with a pitch less than about 45 nm.
9. The method of claim 1 , wherein the conformal silicon oxide spacer material is used as a mask for self-aligned double patterning.
10. The method of claim 1 , wherein the oxidant is selected from the group consisting of oxygen, carbon dioxide, water, nitrous oxide, and combinations thereof.
11. The method of claim 1 , wherein the silicon-containing precursor is an aminosilane.
12. The method of claim 1 , wherein the patterned core material comprises a material selected from the group consisting of spin on carbon, diamond-like carbon, and gapfill ashable hard mask.
13. The method of claim 1 , wherein exposing the substrate to the oxidant comprises flowing an inert gas selected from the group consisting of argon, hydrogen, nitrogen, and helium.
14. The method of claim 1 , wherein the elastic modulus of the conformal silicon oxide spacer material is between about 55 GPa and about 70 GPa.
15. A method of performing multiple patterning on a substrate, the method comprising:
providing a substrate having a patterned core material;
exposing the substrate to alternating exposures of a silicon-containing precursor and an oxidant; and
igniting a plasma when exposing the substrate to the oxidant to form a conformal silicon oxide spacer material having an elastic modulus of at least 55 GPa over the patterned core material, wherein the plasma is ignited using a radio frequency plasma energy of at least about 1000 Joules.
16. The method of claim 15 , further comprising exposing the conformal silicon oxide spacer material to ultraviolet radiation to densify the conformal silicon oxide spacer material.