Silicon material can be used as optical thin films in short-wave infrared (1~3 μm) range, because of its characteristics such as high refractive index, good transparence, easy to match with other layers. Using advanced Sellmeier model, the optical characteristics of silicon thin films have been fitted and calculated. Based on the result, silicon and silicon dioxide are selected as layer materials, and a bandpass filter is designed and fabricated. The center wavelength is about 1.30 μm; the filter with 2 cavities has 32 nm bandwidth and 85.8% transparence at the peak. Combining silicon layers′ high absorption at wavelengths smaller than 1.0 μm, the cut-off range can cover the spectrum range smaller than 1.75 μm.