Double Side Coating of DLC on Silicon by RF-PECVD for AR Application

AbstractDiamond like Carbon (DLC) films were deposited on mono crystalline, double side polished silicon (100) substrates by a capacitively coupled 13.56MHz RF plasma enhanced chemical vapour deposition (RF-PECVD) system, using acetylene (C2H2) as process gas. DLC films were deposited at a constant power of 200W with 100sccm flow of C2H2 and at deposition temperatures of 25°C (RT), 150°C and 300°C. DLC films were characterized by Fourier- transform Infrared Spectroscopy (FTIR), Ellipsometry and Raman Spectroscopy. Characterization of DLC films for anti-reflective (AR) property by FTIR on double side coated silicon at room temperature showed enhancement in maximum transmission of about 89% in 3- 5μm wavelength. Raman and Ellipsometry analysis confirmed the formation of DLC films with Ad/Ag ratio of 0.53- 0.82 and refractive index (n) of 2.3