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Heavy-ion latchup is investigated for analog-to-digital converters. Differences in cross section for various ions show that charge is collected at depths beyond 50 [micro] m, causing the cross section to be underestimated unless long-range ions are used. Current distributions, thermal imaging, and diagnostic tests with a pulsed laser were used to identify latchup-sensitive regions. Latchup in one of the circuit types was catastrophic, even when the power was turned off within 2 ms of a latchup event. Examination of damaged devices with a scanning electron microscope showed that the failures occurred in metallization and contact regions. Current density for failure agrees with pulsed current metallization stress data in the literature. Index Terms--Analog-to-digital converters (ADCs), latchup, radiation effects.

The single event upset (SEU) sensitivity of certain types of linear microcircuits is strongly affected by bias conditions. For these devices, a model of upset mechanism and a method for SEU control have been suggested.

Laser tests performed on a prototype chip to validate new SEU-hardened storage cell designs revealed unexpected latch-up and single-event upset phenomena. The investigations that identified their location show the existence of a topology-dependent dual node upset mechanism. Design solutions are suggested to avoid its occurrence.

Provides information on the single event upset (SEU) sensitivity to certain types of linear microcircuits which is effected by bias conditions. Information on test devices used in this experiment; Methodology used.