Optical interference method for the approximate determination of refractive index and thickness of a transparent layer

摘要: Optical interference fringe measurements of the thickness transparent layers can be rapid, accurate, and nondestructive. If refractive index n layer being measured is known, it may combined directly with information to yield t. If, however, unknown, measurement procedure necessarily becomes more complicated. In this paper, a new simpler optical method presented for approximate determination both t on substrate. The required experimental obtained from single spectrophotometric recording either reflectance or transmittance its theory presented, an application SIPOS (Semi-Insulating POlycrystalline Silicon) described. requires that must uniformly deposited flat substrate, neither absorb nor scatter light passing through it. major approximation inherent in substrate are assumed nondispersive over wavelength region interest.