APPARATUS AND METHODS FOR SCATTEROMETRY OF OPTICAL DEVICES

摘要

In a method for measuring a dimension or angle of a scattering feature of an optical device, such as a photonic crystal, at least part of the array is irradiated with light. A characteristic of light scattered from the array is detected. A comparison algorithm is run on the detected characteristic of the scattered light. The comparison algorithm provides one or more numerical values indicative of the measured dimension or angle. A system for measuring a dimension or angle of a feature of an optical device includes a light source and optics for focusing light from the light source onto a target area of the optical device. A light detector is positioned to detect scattered light from the target area, with the detected light used to create a measured light characteristic. A computer linked to the light detector performs a comparison algorithm on the measured light characteristic and outputs a numerical value of the dimension or angle measured. In method for designing an optical device, such as a photonic crystal for use on an LED, an intended scattered response based on light emission characteristics desired from the optical device is simulated. One or more design parameters of the optical device are varied. An interim reflectance response of the optical device with variation of the parameters is determined. Interim scattered responses are compared to the intended scattered response. One or more scattered responses which match the intended scattered response are selected. An optical device is designed using one or more of the design parameters associated with the selected interim scattered response.