M. Heer, D. Pogany, Vienna University of Technology, Vienna, Austria; M. Street, I. Smith, F. Riedlberger, Zetex Semiconductors plc, Oldham, United Kingdom; D. Bonfert, H. Gieser, Fraunhofer Institute IZM-M, Munich, Germany

Summary: We present a case study of a transient induced latch-up (TLU) problem, which was identified during the development of a 60V, 0.8um BiCMOS power control device. The mechanism was characterized by controlled transient latch-up testing and found to be fairly unusual, being triggered by a fast decreasing not necessarily negative spike or glitchon the positive supply pin. Emission Microscopy (EMMI) and Transient Interferometric Mapping (TIM) successfully located the parasitic SCR structure. TIM is an infra-red laser based technique for back side analysis. TIM analysis enables concurrent imaging of carrier injection and heating in nanosecond timescale providing more detailed information on the SCR action than more often used static photon emission or dynamic TLP / PICA imaging.