Repairing oxygen plasma-damaged on low dielectric constant MSQ (methylsilsesquioxane) films with anneal

Low dielectric MSQ (methylsilsesquioxane) films are obtained by spin-coating deposition on the p-Si (100) wafer. MSQ could be synthesized by one-step processing. Fourier transform infrared spectrometer (FTIR) was used to identify the network structure and cage structure of Si–O–Si bonds. C-V characteristic was used to calculate the dielectric constant. I-V characteristic was used to determine the leakage current density and the breakdown electric field. The results indicate that oxygen plasma exposure damaged the MSQ films by removing the carbon content on the surface of the films. Oxygen plasma exposure on MSQ films form the Si–OH bonds which induce to the increase of the hydrophilicity. The increase of the hydrophilicity on the surface of MSQ films increases the dielectric constant and leakage current density of MSQ films. Both the dielectric constants and leakage current density of MSQ films decreased with anneal at 350°C for 1.5 h in nitrogen ambient.