Two-photon optical-beam-induced current solid-immersion imaging of a silicon flip chip with a resolution of 325 nm.
We report high-resolution subsurface imaging of a silicon flip chip by detection of the photocurrent generated by the two-photon absorption of 1530-nm light from a femtosecond Er:fiber laser. The technique combines the focal sensitivity of two-photon excitation with the enhanced optical resolution of high-numerical-aperture solid-immersion imaging. Features on a sub-1-microm scale are clearly resolvable with high contrast, showing a resolution of 325 nm.
Ramsay
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E
Ultrafast Optics Group, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, UK. e.ramsay@hw.ac.uk
Pleynet
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N
Xiao
D
D
Warburton
R J
RJ
Reid
D T
DT