Laser diode reliability depends on both power and spectral stability over time. This report examines cases in which both corrosion and ionic deposition resulted in wavelength shifts from less than 1 nm to greater than 7 nm in 60 - 100W bars on microchannel coolers. Both corrosion and deposition seemed to be exacerbated by frequent and/or lengthy periods of stagnation in the DI water system. Analytical results including SEM images of FIB cross-sections illustrate deposits of up to several microns thickness of dielectric (oxide) material, as well as voiding caused by corrosion of Ni-plating out from under Au-plating through pinhole defects. Thermal modeling confirms the effect of such features on thermal resistance, correlating to observed wavelength shifts. Actions taken to address these issues are discussed.

Date Published: 23 February 2009
PDF: 10 pages
Proc. SPIE 7198, High-Power Diode Laser Technology and Applications VII, 71980J (23 February 2009); doi: 10.1117/12.809925

Published in SPIE Proceedings Vol. 7198:
High-Power Diode Laser Technology and Applications VII
Mark S. Zediker, Editor(s)