Co₂-laser-assisted plasma-enhanced chemical vapor deposition of silicon dioxide thin film

The plasma enhanced chemical vapor deposition (PECVD) of silicon dioxide (SiO₂) thin films from SiH₄ and N₂O has been executed with and without CO₂ laser illumination. The quality of the film processed under a 10.6 μm CO₂ laser was close to that of a film grown when the substrate was heated to 200°C. Since the temperature of the film substrate under CO₂ laser illumination was only about 55°C, this method should be helpful in processes where a low thermal budget is required. CO₂-laser-assisted PECVD (termed LAPECVD) with a substrate heated to 200°C resulted in a SiO₂ thin film with excellent I-V characteristics and surface morphology, as well as a higher refractive index and lower etching rate in BOE solution. Application of this thin film should be explored.