The chemical bond structure investigation on the Si-O-C composite films with low dielectric constant deposited by high density plasma chemical vapor deposition

Summary form only given, as follows. Si-O-H films with a low dielectric constant were deposited on a ptype Si(100) substrate using a mixture bis-trimethylsilyl-methane (BTMSM) and an oxygen gases and a high density plasma chemical vapor deposition (HDPCVD) system. The plasma density and the electron temperature with the rf power of a 300 W were about 10/sup 12/ cm/sup -3/ and 3 eV, respectively. The BTMSM/(O/sub 2/+BTMSM) gas flow rate ratios change from 25% to 85% and the total gas flow rate is kept about 20 sccm. Fourier transform infrared (FTIR) spectra and X-ray photoelectron spectroscopy (XPS) spectra show that the film has Si-CH/sub 3/ and OH-related bonds. The deposited film composition is composed of about 27 at. % Si, 70 at. % 0 and 3 at. % C, and after annealing C concentration increase and O concentration decrease. In the annealed films, the bonding configuration is Si-O-Si, Si-O-C and Si-CH/sub 3/ bonds. From these result, the attachment of the Si-O-Si ring link with CH/sub 3/ groups is responsible to form the nano-size void in the film, which the dielectric constant is about 2.1.