A unified fabrication process was developed for four complex gratings. One period of each grating contains multiple pairs of ridges/grooves, and a ridge is usually composed of diversified materials. The process was suitable not only for mass fabrication but also for a large area. Moreover, with only one mold, four gratings could be obtained at once. Two samples were fabricated for demonstration. Profile uniformity of each sample was confirmed with broadband infrared (2.5 to ) transmittance spectra. A good agreement between measured and modeling results was observed.