METHOD AND APPARATUS FOR DEPTH PROFILE ANALYSIS BY LASER INDUCED PLASMA SPECTROS COPY

• US 20030016353A1
• Filed: 07/17/2001
• Published: 01/23/2003
• Est. Priority Date: 07/17/2001
• Status: Active Grant

• Current Assignee: National Research Council Canada
• Original Assignee: National Research Council Canada
• Inventors: Detalle, Vincent, Sabsabi, Mohamad
• Granted Patent: US 6,532,068 B2
• Time in Patent Office: Days
• US Class Current: 356/318
• CPC Class Codes: B23K 26/032 using optical means
• CPC Class Codes: B23K 26/0613 having a common axis B23K26/0619 takes precedence
• CPC Class Codes: B23K 26/364 for making a groove or trench, e.g. for scribing a break initiation groove
• CPC Class Codes: G01N 21/718 Laser microanalysis, i.e. with formation of sample plasma

Abstract

In a method of spectrochemical depth-profile analysis of heterogeneous materials, a first burst of ablation laser pulses in a first beam is directed at a sample to form an ablation crater. A second single pulse or burst of laser pulses in a second beam having a smaller width than said first beam is then directed at the bottom of the crater so as to create a plasma that emits radiation representative of a component in the sample without a significant contribution from the walls of the ablation crater. The intensity of radiation from the plasma is measured and the concentration of the selected component is determined from the intensity of the radiation. The depth at which the measurement is taken is then evaluated and the above steps repeated to determined the evolution of concentration of said selected component as a function of depth.

Claims