17 October 2003 Surface analysis by laser-induced desorption time-of-flight mass spectrometry
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Proceedings Volume 4977, Photon Processing in Microelectronics and Photonics II; (2003) https://doi.org/10.1117/12.479418
Event: High-Power Lasers and Applications, 2003, San Jose, CA, United States
We have built and tested a laser induced desorption (LID), electron impact ionization, time-of-flight (TOF) mass spectrometer (MS) designed to nondestructively identify and measure adsorbed contaminants on critical surfaces for the microelectronics and optics industries. The LID-TOFMS combines the capability of a TOF mass spectrometer to measure all the desorbed molecules from a single laser shot with an infrared Er:YAG laser (2.94 micron), which is not strongly absorbed by many transparent optical materials but is strongly absorbed by water, the most common adsorbed surface contaminant, to yield surface composition as a function of position on the sample. The LID-TOFMS was calibrated using an oxalic acid film on a polished stainless steel plate, which also contained adsorbed water. Contaminants on CaF2 surfaces measured by LID-TOFMS include water and hydrocarbons. Desorbed molecules decrease with increasing irradiations at a fixed laser fluence, suggesting that the surface is being cleaned.
© (2003) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Susan Davis Allen, Susan Davis Allen, Jinmei Fu, Jinmei Fu, Yamini Surapaneni, Yamini Surapaneni, Adam J. Hopkins, Adam J. Hopkins, Phillip Davis, Phillip Davis, "Surface analysis by laser-induced desorption time-of-flight mass spectrometry", Proc. SPIE 4977, Photon Processing in Microelectronics and Photonics II, (17 October 2003); doi: 10.1117/12.479418; https://doi.org/10.1117/12.479418

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