Method and system for characterizing light emitting devices
AssigneeSof-Tek Integrators, Inc.
InventorsDaniel C. Morrow, Jonathan Dummer, Stanley Curtis Dodds
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Abstract
Embodiments as disclosed herein provide a method and system that characterizes physical properties, such as thickness, uniformity, polarization, and/or sizes and locations of defect (e.g. defect density distribution) of crystalline structures grown on or thin films deposited on a substrate of a solid state light emitting device. The embodiments disclosed herein generally include exciting the light emitting device with an energy source and analyze optical energy emitted by the crystalline structures grown on or the thin films deposited on the substrate.
Claims34
A method of characterizing a solid state light emitting device, comprising:
- exciting a first light emitting region of the solid state light emitting device;
- exciting a second light emitting region of the solid state light emitting device;
- collecting photons emitted by the first and second light emitting regions;
- obtaining a first spectral power distribution of the photons emitted by the first light emitting region;
- obtaining a second spectral power distribution of the photons emitted by the second light emitting region;
- obtaining, using a processor, at least one color parameter for the first spectral power distribution and at least one color parameter for the second spectral power distribution by fitting one or more Gaussian functions to the first and second spectral power distributions;
- and
- spatially correlating a physical property of the first and second light emitting regions based on the at least one color parameter for the first spectral power distribution and the at least one color parameter for the second spectral power distribution.
An apparatus for characterizing a solid state light emitting device, comprising:
- a power source configured to be coupled to and excite a first and a second light emitting region on the solid state light emitting device;
- a sensor that senses photons emitted by the first and second light emitting regions;
- a spectrometer that obtains a first spectral power distribution of the photons emitted by the first light emitting region and a second spectral power distribution of the photons emitted by the second light emitting region;
- and
- a processor that:
- obtains at least one color parameter for the first spectral power distribution and at least one parameter for the second spectral power distribution by fitting one or more Gaussian functions to the first and second spectral power distributions, and
- spatially correlates a physical property of the first and second light emitting regions based on the at least one color parameter for the first spectral power distribution and the at least one color parameter for the second spectral power distribution.
Dependencies are inferred from the claim text.