9th Annual Soft Error Rate (SER) Workshop – Details

Below are summaries of each of the tutorials and talks. Return to this page following the Workshop to download PDFs of the slides.

Presenter Title Details
8:00 AM (PT) On-Site Registration — Coffee, tea
8:30 AM (PT) Introduction to the Workshop
Austin Lesea, Xilinx Tutorial: Single Event Effects (30 minutes) This tutorial is a technical backgrounder on Single Event Effects (SEE) in semiconductor devices, to establish a baseline understanding of origins, effects, mitigation, and testing. Key points made in this presentation are:

  • SEE have a relatively long history and can affect all semiconductor devices.
  • SEE arise from environmental radiation and present a variety of undesired behaviors.
  • SEE mitigation is possible and SEE susceptibility can be measured.

    After this tutorial, attendees will have general familiarity with radiation effects in semiconductor devices. With this background, they will be primed for the other talks which follow.
  • Gary Swift, Swift Engineering Tutorial: Probability and Statistics for Experimenters (30 minutes) This tutorial is a backgrounder on probability and statistics for SEE experiments. SEE experiments are all about counting, which is easy — but understanding counting statistics is important for planning experiments, analyzing measured data, and interpreting the results. Even if you have no plan to run your own experiments, correctly interpreting the work of others is a cornerstone of applying data to make informed decisions in the design of reliable systems.
    Hirotaka Hirano, Mitsubishi Materials Study of the Alpha Counts from Solder Bump Material at Elevated Temperature and Introduction of Advanced Grade Material (30 minutes) We investigated the impact elevated temperature has on the alpha count for the solder bump materials. As a result, it was revealed that the alpha counts increase at elevated temperature due to the surface diffusion of Po. For this reason, we thought that it is necessary to further reduce the alpha counts of the material in order to satisfy the current product guarantee specifications ( < 0.002 cph/cm2 ) even at elevated temperature. Thus, we successfully developed the advanced grade tin material “HULA grade”. The alpha counts of HULA grade material is very low ( < 0.001 cph/cm2) and never increase at elevated temperature even with aging. In this presentation, we would like to introduce the investigation results and the HULA grade material.
    Paul Muller, IBM Assessment of Alpha Particle Susceptibility of Product Chips Through Accelerated Tests (30 minutes) There are several methods for experimentally assessing the soft error rates (SER) of product chips. If it is not an accelerated test, large numbers of chips are exposed to the naturally occurring cosmic rays for a long period of time ranging from months to years.

    Accelerated tests can be carried out using particle accelerators: highly energetic protons or neutrons emulate the impact caused by naturally occurring cosmic rays, but with a flux several orders of magnitude larger than the naturally occurring flux. In order to run an accelerated test for alpha particle sensitivity, one would typically bring a foil source, like Thorium or Americium, into close vicinity to the chip. But that is only feasible if it is a wire bonded chip. If it is a solder bump flip chip, this is very difficult because the space needed for getting the foil source into close vicinity of the chip is occupied by the solder bumps and the substrate.

    We are showing results from a radioactive underfill experiment with a product chip. In this case, the space between the solder bumps, which is typically filled with an ultra-low underfill compound, is filled with a highly radioactive epoxy material. Acceleration factors of 100,000 and higher over naturally occurring alpha fluxes can be achieved. With that, the mean time between events is only minutes to hours, and the time for obtaining statistically meaningful numbers of events is only days or weeks.
    Jaret Heise, Sanford Underground Research Facility Opportunities at the Sanford Underground Research Facility (30 minutes) Building on rich legacies in both mining and transformational physics research, the Sanford Underground Research Facility (SURF), in South Dakota, has been operating as a dedicated research facility for over 10 years. A brief overview of the facility and the science program will be presented. SURF has significant expansion opportunities, and applications from interested research and testing groups are welcome.
    12:00 Noon – 1:00 PM (PT) Lunch and Exhibits
    Jeff Barton and Eric Crabill, Xilinx An Introduction to Real-Time Testing (30 minutes) This presentation provides an introduction to real time testing — also known as atmospheric testing — an accepted test methodology referenced in the JESD89 specification. Learn about its advantages, what is involved in setting up and maintaining experiments, and operational pitfalls to avoid.
    Norbert Seifert, Intel On the Efficacy of Using Proton Beams for Estimating Neutron-Induced Soft Error Rates (30 minutes) This work investigates the feasibility of using high energy proton beams in lieu of, or to complement, broad energy spectrum neutron beams for accelerated testing of the cosmic component of terrestrial soft error rates (SER). Logic and memory devices manufactured in three recent technologies were tested at various proton facilities and their single event upset cross sections compared to soft error rates measured at the Los Alamos Neutron Science Center (LANSCE). Linear energy transfer and soft error simulations were conducted to understand the limits of using proton beam facilities. Both simulation results and experimental data demonstrate that a good correlation between proton cross-section and LANSCE neutron SER can be established for tested devices and technologies.
    Francis Classe, Cypress New High Energy Neutron Spallation Beam, ChipIr, at Appleton-Reutherford Lab at Oxford (30 minutes) This presentation discusses the correlation of a new high-energy neutron spallation beam, ChipIr, at the Appleton-Reutherford Laboratory in Oxford, England. Both Flash memories and SRAM products were tested at the ChipIr beam, and correlated to LANSCE and TRIUMF beams accordingly. The data indicates that the ChipIr beam produces results approximately 1.3 – 2x compared to that of TRIUMF and LANSCE accordingly, making it a very acceptable choice for high energy neutron studies.
    3:30 PM (PT) Close of Workshop