| Plasma enhanced chemical vapor deposition (PECVD) technology firstly developed with the semiconductor industry, and being widely used in microelectronics industry. The films deposited by PECVD have good quality with uniformity, step coverage, compactness, adhesion, corrosion resistance, and high deposition rate. Therefore, PECVD technology applies to binary optics, gradient refractive index optical thin-film, thin film laser damage resistance and other aspects. However, there will be large numbers of particles and impurities in optical films deposited by PECVD. The key and difficult is how to control the film refractive index and deposition rate accurately.In this paper, the possibility of using PECVD technology to prepare optical anti-reflective films based on silicon wafer and K9 glass has be discussed. Deposition process and different process parameters on properties of optical thin films are explored. Further more, optical anti-reflective films samples have be designed and produced, the error and evaluation was also analyzed.By controlling the film deposition process parameters, optical constants of thin films can be changed and match optical thin films standards. When thin film materials extinction coefficient k <10-4:1. SiO2 thin films refractive index changes in the range of 1.50-1.54, SiNx thin films refractive index changes in the range of 1.85-1.93, SiOxNy thin films refractive index in the range of 1.57-1.76;2. The deposition rate of SiO2, SiNx, and SiOxNy thin film materials could being control in the range of 10nm/min-50nm/min by changing SiH4 flow rate.3. The thickness of the films can be precisely achieved with accuracy below 5% when the thin films deposition rate in the range of 20nm/min-40nm/min;4. Using SiO2, SiNx, and SiOxNy as thin film materials (refractive index changes from 1.53 to 1.94), the optical anti-reflective films in the visible range (400nm～800nm) with peak transmittance of 96.11% and average transmittance of 93.8% is successful produced.
|
PDF Full Text Request