Capped ALD films for doping fin-shaped channel regions of 3-D IC transistors
Disclosed herein are methods of doping a fin-shaped channel region of a partially fabricated 3-D transistor on a semiconductor substrate. The methods may include forming a multi-layer dopant-containing film on the substrate, forming a capping film comprising a silicon carbide material, a silicon nitride material, a silicon carbonitride material, or a combination thereof, the capping film located such that the multi-layer dopant-containing film is located in between the substrate and the capping film, and driving dopant from the dopant-containing film into the fin-shaped channel region. Multiple dopant-containing layers of the film may be formed by an atomic layer deposition process which includes adsorbing a dopant-containing film precursor such that it forms an adsorption-limited layer on the substrate and reacting adsorbed dopant-containing film precursor. Also disclosed herein are multi-station substrate processing apparatuses for doping the fin-shaped channel regions of partially fabricated 3-D transistors.
1. A method of depositing a film comprising silicon and oxygen onto a substrate, the method comprising:
(a) providing the substrate in a chamber;
(b) introducing into the chamber a silicon-containing precursor selected from the group consisting of caged siloxanes;
(c) purging the chamber with a purge gas;
(d) introducing an oxidant into the chamber; and
(e) purging the chamber with the purge gas,
wherein (b)-(e) are repeated until a desired thickness of the film is deposited.
2. The method of claim 1 , wherein the oxidant is selected from the group consisting of oxygen, ozone, hydrogen, nitrous oxide, carbon monoxide, and mixtures thereof.
3. The method of claim 1 , wherein the oxidant comprises an oxidative plasma.
4. The method of claim 3 , wherein the oxidative plasma is generated in the chamber housing the substrate.
5. The method of claim 3 , wherein the oxidative plasma is generated remotely.
6. The method of claim 1 , wherein the film comprises carbon.
7. The method of claim 6 , wherein a concentration of carbon in the film is between about 1 and 4 g/cm 3 .
8. The method of claim 1 , wherein the film is formed at a temperature between about 25° C. and 450° C.
9. The method of claim 1 , wherein the silicon-containing precursor is selected from the group consisting of silsesquioxane.
10. The method of claim 1 , wherein the silicon-containing precursor is chemically adsorbed onto a surface of the substrate to form a chemisorbed precursor on the surface of the substrate.
11. The method of claim 10 , wherein introducing the oxidant is performed after purging the chamber in (c) and wherein the oxidant reacts with chemisorbed precursor on the surface of the substrate.
12. The method of claim 10 , wherein the substrate is heated.