Charles J. Montrose

IBM experiments in soft fails in computer electronics (1978–1994)

This review paper has described the experimental work at IBM over the last fifteen years in evaluating the effect of cosmic rays on terrestrial electronic components. This work originated in 1978, went through several years of research to verify its magnitude, and became a significant factor in IBM`s efforts toward improved product reliability.

Field testing for cosmic ray soft errors in semiconductor memories

This paper presents a review of experiments performed by IBM to investigate the causes of soft errors in semiconductor memory chips under field test conditions. The effects of alpha-particles and cosmic rays are separated by comparing multiple measurements of the soft-error rate (SER) of samples of memory chips deep underground and at various altitudes above the earth. The results of case studies on four different memory chips show that cosmic rays are an important source of the ionizing radiation that causes soft errors. The results of field testing are used to confirm the accuracy of the modeling and the accelerated testing of chips.

Cosmic ray soft error rates of 16-Mb DRAM memory chips

Manufactured 16-Mb DRAM memory chips use three different cell technologies for bit storage: stacked capacitors, trenches with internal charge, and trenches with external charge. We have measured the soft fail probability of 26 different 16-Mb chips produced by nine vendors to evaluate whether the different cell technologies have an impact on the chip soft error rate. This testing involved irradiation with neutrons, protons, and pions, the principle hadrons of terrestrial cosmic rays. The results show clear differences in soft-fail sensitivity, which appears to be related to the cell structure.