Study of fabrication of 16-channel micro integrated filter

Multi-spectrum imaging system is tending to become smaller, more integrated, lighter and more spectrum channels, and spectrum-dividing multi-channel filter is one of critical elements of the system. A new effective technology is needed to meet the requirement. A new method named combined etching technology was presented here by adjusting the thickness of space layer of F-P filter. Traditional coating technology was combined with ion etching and masking technique to fabricate multi-channel integrated filters. A 16-channel micro integrated narrow band pass filter was fabricated within a small size substrate, whose feature size of unit filter width is 0.7 mm, relative half width of peak transmission is less than 1.0%, and peak position location accuracy is beneath 0.25%. This method not only meets the requirement of integrating more filters, but also develops the fabrication technology of thin film.