Method for accurately determining the thickness and/or elemental composition of small features on thin-substrates using micro-XRF

摘要

A method for X-ray Fluorescence (XRF) analysis includes directing an X-ray beam onto a sample and measuring an XRF signal excited from the sample, in a reference measurement in which the sample includes one or more first layers formed on a substrate, and in a target measurement after one or more second layers are formed on the substrate in addition to the first layers, so as to produce a reference XRF spectrum and a target XRF spectrum, respectively. A contribution of the first layers to the target XRF spectrum is reduced using the reference XRF spectrum. A parameter of at least one of the second layers is estimated using the target XRF spectrum in which the contribution of the first layers has been reduced.

主权项

1. A method for X-ray Fluorescence (XRF) analysis, comprising:
directing an X-ray beam onto a sample; measuring an XRF signal excited from the sample, in a reference measurement in which the sample comprises one or more first layers formed on a substrate, so as to produce a reference XRF spectrum; re-measuring the XRF signal excited from the sample in a target measurement after one or more second layers are formed on the substrate in addition to the first layers, so as to produce a target XRF spectrum that comprises first spectral components contributed by the first layers and second spectral components contributed by the second layers; reducing a level of contribution of the first spectral components to the target XRF spectrum using the reference XRF spectrum; and estimating a parameter of at least one of the second layers using the target XRF spectrum in which the level of contribution of the first spectral components has been reduced.