Methods and systems for performing simultaneous spectroscopic measurements of
semiconductor structures over a broad range of angles of incidence (AOI),
azimuth angles, or both, are presented herein. Spectra including two or more sub-ranges of angles of incidence,
azimuth angles, or both, are simultaneously measured over different sensor areas at high
throughput. Collected light is linearly dispersed across different photosensitive areas of one or more detectors according to
wavelength for each subrange of AOIs,
azimuth angles, or both. Each different photosensitive area is arranged on the one or more detectors to perform a separate spectroscopic measurement for each different range of AOIs, azimuth angles, or both. In this manner, a broad range of AOIs, azimuth angles, or both, are detected with high
signal to
noise ratio, simultaneously. This approach enables high
throughput measurements of high
aspect ratio structures with high
throughput, precision, and accuracy.