Semiconductor manufacturing method for inter-layer insulating film
Provided is a technology capable of improving the reliability of a semiconductor device using a SiOC film as an interlayer film. In the invention, by forming an interlayer film from a SiOC film having a Si—CH 3 bond/Si—O bond ratio less than 2.50% or having a strength ratio determined by the FT-IR of a Si—OH bond to a SiO—O bond exceeding 0.0007, a strength ratio of a SiH bond to a SiO—O bond at a wavelength of 2230 cm −1 exceeding 0.0050 and a strength ratio of a Si—H bond to a SiO—O bond at a wavelength of 2170 cm −1 exceeding 0.0067, the interlayer film has a relative dielectric constant of to 3 or less, and owing to suppression of lowering in hardness or elastic modulus, has improved mechanical strength.
1. A manufacturing method of a semiconductor device comprising:
(a) forming a SiOC film as an interlayer over a semiconductor substrate;
(b) forming a TEOS film on the SiOC film;
(c) forming a wiring groove in the SiOC film and the TEOS film;
(d) forming a metal layer both inside the wiring groove and on the TEOS film outside the wiring groove; and
(e) removing the metal layer outside the wiring groove by a chemical mechanical polishing method so as to leave the metal layer in the wiring groove,
wherein a ratio of a Si—CH3 bond to a Si—O bond of the SiOC film as determined by FT-IR is within a range of 2.05 to 2.49%.
2. A manufacturing method of a semiconductor device according to claim 1 , wherein the SiOC film has a relative dielectric constant of 3 or less.
3. A manufacturing method of a semiconductor device according to claim 1 , wherein the SiOC film has a hardness of 2.8 Gpa or greater.
4. A manufacturing method of a semiconductor device according to claim 1 , wherein the SiOC film has an elastic modulus of 18 Gpa or greater.
5. A manufacturing method of a semiconductor device according to claim 1 , wherein the SiOC film is formed by plasma CVD method.
6. A manufacturing method of a semiconductor device according to claim 1 , wherein the SiOC film is formed under the following film forming conditions: pressure between 400 and 600 Pa, DMDMOS flow rate between 200 and 350 sccm, He flow rate between 100 and 200 sccm, RF power of 3000 to 4000 W and substrate temperature between 350 and 400° C.
7. A manufacturing method of a semiconductor device according to claim 1 , wherein the metal layer in the wiring groove provides a wiring, and the wiring is damascene wiring having copper as a main conductor layer.