KLA has been granted a patent for a laser-sustained plasma (LSP) light source with reverse vortex flow. The invention includes a gas containment structure with gas delivery lines, gas inlets, and gas outlets to generate a reverse vortex flow. It also features a laser pump source to sustain a plasma and a light collector element to collect emitted light. GlobalData’s report on KLA gives a 360-degree view of the company including its patenting strategy. Buy the report here.
According to GlobalData’s company profile on KLA, Defect detection models was a key innovation area identified from patents. KLA's grant share as of September 2023 was 57%. Grant share is based on the ratio of number of grants to total number of patents.
Laser-sustained light source with reverse vortex gas flow
A recently granted patent (Publication Number: US11776804B2) describes a laser-sustained light source that utilizes a gas containment structure to generate a plasma and collect broadband light emitted from the plasma. The gas containment structure includes a body, a neck, and a shaft, with multiple nozzles positioned in or below the neck. Gas delivery lines are fluidically coupled to the nozzles to deliver gas, and gas inlets and outlets are arranged to create a vortex gas flow within the structure. A gas seal is located at the base of the structure to maintain containment.
The light source also includes a laser pump source that generates an optical pump to sustain the plasma within the vortex gas flow. A light collector element is configured to collect at least a portion of the broadband light emitted from the plasma. The patent claims also describe various configurations and arrangements for the gas containment structure, including the use of between 2 and 10 nozzles, inclined delivery lines in a spiral arrangement, and the positioning of gas inlets and outlets at the periphery or center of the gas seal.
The patent also mentions the use of a distribution manifold, a binding for stabilizing the nozzles, and optical shielding to protect the gas seal from the broadband light. Additionally, the patent discusses the use of different gases within the gas containment structure, such as Xe, Ar, Ne, Kr, He, N2, H2O, O2, H2, D2, F2, CF6, or mixtures thereof.
Furthermore, the patent describes a characterization system that incorporates the laser-sustained light source, along with illumination optics to direct the broadband light to samples, collection optics to collect light from the samples, and a detector assembly.
Overall, this patent presents a laser-sustained light source with a gas containment structure that enables the generation and collection of broadband light emitted from a plasma. The various configurations and arrangements described in the patent offer flexibility in designing and optimizing the performance of the light source for different applications.