Methods and apparatus for spectroscopic identification and/or calibrated quantification of surface concentration of materials

Inventors

Reid, Michael R.

Assignees

Photon Systems Inc

Abstract

Apparatus and methods for creating deposits of uniformly spaced or uniformly overlapping droplets of selected chemicals where each droplet has an a priori known amount of the selected chemical or chemicals is taught (including biological and microbial materials). In some embodiments the deposits may be used as samples of different but known concentrations that may be used to calibrate spectroscopic inspection instruments to enable such instruments to not only provide identification in situ of unknown materials but also to provide calibrated and traceable surface concentrations of such materials. In some embodiments, such calibrated instruments may be used in enhanced processes for validating the cleanliness of manufacturing surfaces such as surfaces of equipment used in the preparation of pharmaceuticals, food, or semiconductor devices. Such instruments may be used to ensure adequate purity, or non-contamination, of surfaces of products themselves or packaging materials or of locations where such products will be used. Such calibrated instruments may also be useful in detecting cleanliness of non-manufacturing surfaces where contamination may be of concern, whether they be public or private spaces such as laboratories, restaurants, airports, satellites or other spacecraft. In some embodiments, such instruments may range from deep UV instruments to far infrared instruments or beyond.

Core Innovation

The invention provides a method of calibrating a spectroscopic surface analysis instrument to identify at least one material of interest and to provide a quantitative indication of the at least one material of interest that is detected. The method uses an instrument having a housing, a source capable of producing excitation radiation directed onto a surface to be examined, at least one optical element for directing excitation radiation and for receiving emission radiation, a detector for detecting emission radiation from at least one location, and control electronics for operating the instrument.

Quantitative calibration data are created and stored using calibration mode operation with a plurality of sample surfaces. Each sample surface has at least one of the at least one material of interest with a known concentration, and data are collected from detected emission radiation returned from each sample surface.

The collected data are processed to provide calibration data for a desired range of concentrations of the at least one material of interest, and the stored calibration data are used for comparison when examining a surface to be tested having unknown material. The comparison ascertains information about the quantitative indication that may be present.

Claims Coverage

Two independent claims are identified. The claims center on the instrument architecture, an electronic circuit that determines material correspondence and quantitative indication, and calibration mode operation on multiple sample surfaces with known concentrations to generate and store calibration data for a desired concentration range.

Across the independent claims, the calibration approach is grounded in a spectroscopic instrument architecture, electronic processing to determine material correspondence and produce a quantitative indication, and generation and storage of quantitative calibration data using multiple sample surfaces with known concentrations for comparison to a surface to be tested.

Stated Advantages

Documented Applications