Optical probing of a silicon integrated circuit using electric-field-induced second-harmonic generation

By using the electric-field-induced second-harmonic generation effect, we have detected electrical signals present on a complementary metal-oxide-semiconductor (CMOS) integrated circuit in a noncontact geometry. Femtosecond pulses with a wavelength of 2.16 mu m were incident on the device and the second harmonic at 1.08 mu m exhibited a field-dependent behavior. The conversion efficiency from the fundamental to the second harmonic was estimated to be -103 dB.