Phase thickness deviations' influence on properties of antireflection coatings for near infrared detectors

Investigation deals with problems of computer-aided design of wide-band antireflection (AR) coatings for semiconductor photosensitive devices (discrete photo receivers, CCD-cameras, modern security systems and others) for spectral region 0.9 μm - 1.7 μm. In practice during deposition of multilayer coatings some deviations of desired coatings' thicknesses always occurs which worsens antireflection properties of the coatings. It is important to know how the phase thickness deviations influence on transmission spectrum of the system: substrate - AR coating. As a result of the analysis it is shown that six-layer structure possesses the lowest reflection and high stability when phase thickness deviations' occurs.