TEOS deposition method
View Patent ↗A TEOS deposition method. A mixture of gases is introduced into a process chamber, in which the mixture of gases comprises tetra-ethyl-ortho-silicate (TEOS) and N 2 . Compressive stress of a TEOS oxide film is increased by activating the mixture of gases.
1. A deposition method of PE-TEOS oxide layer having an increased compressive stress, comprising:
introducing a mixture of process gases into a process chamber, the mixture of process gases comprising tetra-ethyl-ortho-silicate(TEOS) and N 2 ; and
forming a plasma by activating the mixture of process gases to deposit an oxide layer on a substrate, wherein the N 2 /TEOS has a flow rate ratio between about 0.29 and about 0.46.
2. The method as claimed in claim 1 , further comprising introducing O 2 and He.
3. The method as claimed in claim 1 , wherein the oxide layer is deposited at a process pressure of 5˜8 Torr.
4. The method as claimed in claim 1 , wherein the oxide layer is deposited at a process temperature of 300° C.˜500°°C.
5. The method as claimed in claim 1 , wherein the TEOS has a flow rate of 6500 sccm˜10500 sccm.
6. The method as claimed in claim 1 , wherein the oxide layer is deposited at a deposition rate of 120 Å/s˜150 Ås.
7. A PE-TEOS oxide layer deposited according to the deposition method of claim 1 , which has a thickness of 6000˜9000 Å, a uniformity lower than 1.8, and compressive stress more than −2.55×10 9 dynes/cm 2 .
8. A method for depositing an inter metal dielectric layer over a plurality of conductive lines, the method comprising:
depositing a first oxide layer having a compressive stress on the conductive lines by a PECVD method;
depositing a second oxide layer having a tensile stress on the first oxide layer by a SACVD method; and
depositing a third oxide layer on the second oxide layer by a PECVD method with a plasma from a mixture of process gases comprising TEOS and N 2 , the third oxide layer having a compressive stress greater than of the first oxide layer, wherein the N 2 /TEOS has a flow rate ratio between about 0.29 and about 0.46.
9. The method as claimed in claim 8 , further comprising introducing O 2 and He.
10. The method as claimed in claim 8 , wherein the third oxide layer is deposited at a process pressure of 5˜8Torr.
11. The method as claimed in claim 8 , wherein the third oxide layer is deposited at a process temperature of 300° C.˜500° C.
12. The method as claimed in claim 8 , wherein the TEOS has a flow rate of 6500 sccm˜10500 sccm.
13. The method as claimed in claim 8 , wherein the third oxide layer is deposited at a deposition rate of 120 Å/s˜150 Ås.
14. An interconnect structure, comprising:
a substrate;
two metal lines disposed on the substrate; and
an oxide film disposed on the substrate and the metal lines, wherein the oxide film comprises a void between the metal lines, and the void is within the oxide film and under the surface of the metal lines, the oxide film is formed with a plasma from N2 and TEOS, the N 2 / TEOS has a flow rate ratio between about 0.29 and about 0.46, and the oxide film has a compressive stress more than −2.55×10 9 dynes/cm 2 .
15. A deposition method of PE-TEOS oxide layer having an increased compressive stress, comprising:
introducing a mixture of process gases into a process chamber, the mixture of process gases comprising tetra-ethyl-ortho-silicate(TEOS) and an N containing gas selected from the group consisting of NO, N 2 O and NH 3 ; and
forming a plasma by activating the mixture of process gases to deposit an oxide layer on a substrate, wherein the N containing gas/TEOS has a flow rate ratio between about 0.29 and about 0.46.
16. The method as claimed in claim 15 , further comprising introducing O 2 and He.
17. A method for depositing an inter metal dielectric layer over a plurality of conductive lines, the method comprising:
depositing a first oxide layer having a compressive stress on the conductive lines by a PECVD method;
depositing a second oxide layer having a tensile stress on the first oxide layer by a SACVD method; and
depositing a third oxide layer on the second oxide layer by a PECVD method with a plasma from a mixture of process gases comprising TEOS and an N containing gas selected from the group consisting of NO, N 2 O and NH 3 , the third oxide layer having a compressive stress greater than of the first oxide layer, wherein the N containing gas/TEOS has a flow rate ratio between about 0.29 and about 0.46.
18. The method as claimed in claim 17 , further comprising introducing O 2 and He.