Semiconductor device and method for atomic layer deposition of a dielectric over a substrate
A method includes performing an atomic layer deposition (ALD) process to deposit a dielectric material over a substrate, curing the deposited dielectric material using an ultra violet (UV) light, and annealing the deposited dielectric material after the curing.
1. A method comprising:
performing multiple cycles of an atomic layer deposition (ALD) process, wherein the performing of one cycle includes:
supplying a gas comprising SiH 3 N(C 3 H 7 ) 2 and O 3 to a deposition chamber having a substrate to deposit a dielectric material over the substrate; and
supplying an O 2 plasma to the deposition chamber after the supplying of the gas;
curing the deposited dielectric material using an ultra violet (UV) light; and
annealing the deposited dielectric material after the curing, wherein the annealing comprises a steam anneal process performed at a temperature below about 450° C. and for a time interval greater than about 30 minutes.
2. The method of claim 1 , wherein a flow rate of SiH 3 N(C 3 H 7 ) 2 is between about 50 standard cubic centimeter per minute (sccm) to about 100 sccm, and a flow rate of O 3 is between about 4000 sccm to about 8000 sccm.
3. The method of claim 2 , wherein the ALD process is performed at a pressure between about 1.5 torr to about 2.2 torr.
4. The method of claim 1 , further comprising removing one or more gases from the deposition chamber after the supplying the gas and before the supplying the O 2 plasma.
5. The method of claim 1 , wherein the UV light has a wavelength between about 200 nm to about 400 nm.
6. The method of claim 5 , wherein the curing is performed at a temperature between about 10° C. to about 450° C.
7. The method of claim 6 , wherein the curing is performed for a time interval between about 1 minute to about 4 minutes.
8. The method of claim 1 , wherein O—Si—O—H bonds are formed at a surface of the substrate when the gas comprising SiH 3 N(C 3 H 7 ) 2 and O 3 is introduced to the deposition chamber due to chemical reactions with the O 3 .
9. The method of claim 8 , wherein the SiH 3 N(C 3 H 7 ) 2 reacts with the O—Si—O—H bonds to form O—Si—O—SiH 3 bonds through chemisorption, forming a layer of insulation material.
10. The method of claim 9 , wherein the O 3 reacts with the O—SiH 3 bonds to form O—Si—OH bonds, oxidizing the layer of insulation material.
11. The method of claim 10 , wherein the O—Si—OH bonds of the layer of insulation material react with the O 2 plasma and forms O—Si—O bonds, turning top portions of the layer of insulation into silicon oxide.
12. The method of claim 1 , wherein the deposited dielectric material is formed such that it has a wet etch rate (WER) that is uniform from a top surface of the deposited dielectric material to a bottom surface of the deposited dielectric material.
13. The method of claim 1 , wherein the steam anneal process is performed for a time interval between about 30 minutes to about 120 minutes.
14. A method comprising:
filling a recess over a substrate with an insulation material using an atomic layer deposition (ALD) process comprising a first deposition cycle including:
forming a first layer of the insulation material using a gas comprising SiH 3 N(C 3 H 7 ) 2 and O 3 ; and
treating the first layer using an O 2 plasma;
and performing a post treatment to reduce an etching rate of the insulation material, wherein the performing the post treatment comprises:
curing the insulation material using an ultra violet (UV) light; and
performing a steam anneal process over a time interval greater than about 30 minutes at temperatures below about 450° C. to the insulation material after the curing.
15. The method of claim 14 , wherein the ALD process further comprises a second deposition cycle after the first deposition cycle, wherein the second deposition cycle forms a second layer of the insulation material over the first layer of the insulation material.
16. The method of claim 14 , wherein the curing process is performed at temperatures below about 450° C.
17. A method of forming a Fin-Field Effect Transistor (FinFET) comprising:
forming a fin protruding above a substrate;
performing multiple cycles of an atomic layer deposition (ALD) process to deposit an oxide film in a recess adjacent to the fin, wherein the performing of one cycle of the ALD process comprises:
supplying a gas comprising a precursor SiH 3 N(C 3 H 7 ) 2 and an oxidant O 3 to a deposition chamber having the substrate to form a first layer of the oxide film;
removing the gas from the deposition chamber; and
performing a plasma process using an O 2 plasma to treat the first layer of the oxide film;
curing the oxide film using an ultra violet light; and
annealing the oxide film using a steam anneal process performed at a temperature between about 350° C. and about 450° C. over a time interval greater than about 30 minutes.
18. The method of claim 17 , wherein the curing is performed at temperatures lower than about 450° C.
19. The method of claim 17 , wherein the plasma process is performed with a flow rate of O 2 plasma between about 50 sccm to about 100 sccm and a pressure of about 1.5 torr to about 2.2 torr.
20. The method of claim 17 , wherein the plasma process is performed with a temperature between about 350° C. and about 450° C.