Method for forming low dielectric layer of semiconductor device
View Patent ↗Disclosed is a method for forming a low dielectric layer of a semiconductor device. The method includes the steps of forming a low dielectric polymer layer on a semiconductor substrate and performing an in-situ plasma-assistant surface modification process with respect to the low dielectric polymer layer, thereby forming an adhesion promoter layer on the low dielectric polymer layer. The method prevents a film from being delaminated at an interfacial surface due to film stress or adhesion fault, after processes for forming the low dielectric layer and a low resistance metal wiring have been completed to achieve semiconductor devices operated at a high speed.
1. A method for forming a low dielectric layer of a semiconductor device, the method comprising the steps of:
i) forming a low dielectric polymer layer on a semiconductor substrate;
ii) performing an in-situ plasma-assistant surface modification process with respect to the low dielectric polymer layer, wherein an adhesion promoter layer having a bonding structure of S—H—N or Si—O—N is formed on the low dielectric polymer layer through the in-situ plasma-assistant surface modification process.
2. The method as claimed in claim 1 , wherein the low dielectric polymer layer includes material having a C—H—O bonding structure or Si—O—C—H bonding structure.
3. The method as claimed in claim 1 , wherein SiH 4 —N 2 O gas or N 2 —NH 3 gas is used as plasma gas when the in-situ plasma-assistant surface modification process is carried out.
4. The method as claimed in claim 3 , wherein the adhesion promoter layer formed by reacting SiH 4 , N 2 O, N 2 and NH 3 gases in a plasma state with the surface of the low dielectric polymer having a bonding structure of C—H—O or Si—O—C—H.
5. The method as claimed in claim 1 , wherein remote or direction plasma excited through microwave or RF is used when performing the in-situ plasma-assistant surface modification process.
6. The method as claimed in claim 1 , wherein SiH 4 —N 2 O gas or N 2 —NH 3 gas is used as plasma gas and a process temperature is maintained in a range about 300 to 450° C. when performing the in-situ plasma-assistant surface modification process.
7. The method as claimed in claim 1 , wherein, when the in-situ plasma-assistant surface modification process is carried out, a flow rate of SiH 4 is about 30 to 120 sccm, a flow rate of N 2 O is about 1000 to 1200 sccm, a flow rate of N 2 is about 100 to 200 sccm, a flow rate of NH 3 is about 300 to 600 sccm, HF is in a range about 0.1 to 1.0 KW, and LF is in a range about 0.1 to 2.0 KW.
8. The method as claimed in claim 1 , wherein the low dielectric polymer layer includes silicon oxide.
9. The method as claimed in claim 1 , wherein the low dielectric polymer layer is used as an interlayer or a passivation layer.