Patent ID: 7483148

Claim:
A method of monitoring fabrication of, or the end result of fabrication of a process sample comprised of a sequence of at least one very thin layer of material deposited thereonto, said layer having a thicknesses on the order of less than about 100 Angstroms, said method comprising the steps of: a) providing a process sample, and a witness sample other than a light fiber, said process sample having relatively no, or a very thin layer of a dielectric on a surface thereof, and said witness sample having a relatively thick dielectric on a surface thereof; b) before and/or during and/or after causing deposition of a thin layer of material on to both the prosess and witness samples, obtaining spectroscopic ellipsometric data from the witness sample by causing a polarized beam of polychromatic electromagnetic radiation to approach said witness sample at an oblique angle of incidence, interact with said witness sample and then enter a detector, to the end that said detector develops output data for said witness sample; c) analyzing said ellipsometric data to arrive at the thickness and/or optical constants of the material deposited onto the witness sample and attributing said result to the process sample; d) said method further comprising performing at least one selection from the group consisting of: storing at least some data provided by said data detector in machine readable media; analyzing at least some of the data provided by said data detector and storing at least some of the results of said analysis in machine readable media; displaying at least some data provided by said data detector by electronic and/or non-electronic means; analyzing at least some of the data provided by said data detector and displaying at least some of the results of said analysis by electronic and/or non-electronic means; causing at least some data provided by said data detector to produce a signal which is applied to provide a concrete and tangible result; analyzing at least some of the data provided by said data detector and causing at least some thereof to produce a signal which is applied to provide a concrete and tangible result.