Back to results
US 2001/0043327 A1Published application
Spectral identification system
OwnerBryan Barney, Leonard Kamlet +1inventors
InventorsBryan Barney, Leonard Kamlet, Alson Spores
Life of this patent
Estimating the term…
Abstract
A method and apparatus for spectral identification of a material based on a spectral signature. The method is ideally suited for thin film substrate characterization, as found in semiconductor wafer and optical thin film processing.
Claims17
A spectral identification system which includes:
- a) an broad spectrum light source with wavelengths from ultra-violet to near infra-red;
- b) an illumination optical fiber coupled to said light source for transmission light from the light source for illuminating a sample adjustable to a fixed angle of incidence relative to the sample;
- c) a detection fiber for receiving reflected light from the surface of a sample or product adjustable to a fixed angle of incidence relative to the sample or product coupled to a light detector;
- d) said light detector capable of collecting light across a plurality of optical frequencies of light in the ultra-violet to near infra-red and in communication with electronics for translating the detected light into an electrical signal;
- e) a processor for receiving said electrical signals and comparing said signals to a preprogrammed database for identifying the category of the product;
- and
- f) an output circuit to signal the samples category.
4 more elements
A spectral identification system which includes:
- a) a quartz-tungsten-halogen light source;
- b) an optical fiber coupling said lamp to a beam splitter with a lens for focusing light to illuminate a sample, and an adjustable mount allowing for a angle of incidence of light at normal incidence relative to the sample or product;
- c) a means of mounting the optical fiber and beam splitter on a process tool chamber so that an inline measurement can be performed;
- d) a second lens for focusing the light onto a receiving fiber, also attached to the beam splitter;
- e) a silicon based ccd-array detector coupled to said receiving fiber;
- f) electronics capable of translating a signal from said detector into an electrical signal;
- g) a processor for receiving said electrical signal to determine the signature of this multi-wavelength spectral response, and through a comparison with a database of expected product signatures to identify the sample or product as being a member of one of two or more categories of product;
- and
- h) a means of sending an electrical signal output to signify to which category the product belongs.
6 more elements
A spectral identification system which includes:
- a) a quartz-tungsten-halogen light source;
- b) an optical fiber coupled to said light source to a beam splitter with a lens for focusing the light and illuminating a sample, and an adjustable mount allowing for a angle of incidence of light at normal incidence relative to the sample;
- c) a means of mounting the optical fiber and beam splitter on a process tool chamber so that an inline measurement can be performed;
- d) a second lens for focusing the light onto a receiving fiber, also attached to the beam splitter;
- e) a silicon based CCD array detector;
- f) electronics for translating the detector signal into an electrical voltage or current.
- g) a processor for receiving said signal that signal to determine the signature of this multi-wavelength spectral response and comparison of the signature with a preprogrammed database of expected product signatures to identify the sample or product as being one of the following categories:
- 1. semiconductor substrate with no intentionally deposited layers;
- 2. semiconductor wafer with blanket oxide as top layer, with or without metal directly beneath it;
- 3. semiconductor wafer with metal as top layer
- 4. semiconductor wafer with patterned oxide as top layer, with metal directly beneath it (and exposed metal corresponding to the pattern in the oxide);
- 5. semiconductor wafer with photoresist over metal as the top two layers;
- 6. semiconductor wafer with photoresist as the top layer and a material other than metal as the second layer;
- and
- h) a means of sending an electrical signal output to signify to which category the product belongs.
12 more elements
Dependencies are inferred from the claim text.