Terrestrial Neutron-Induced Soft Errors in Advanced Memory Devices

The following sections are included:

• PREFACE

• ABOUT THE AUTHORS

• CONTENTS

This chapter reviews the historical and current developments in the field of terrestrial neutron-induced single event effects (SEEs) and the significance of SEU (Single Event Upsets) of memory devices, particularly SRAMs. An explanation of the physical mechanism of SEEs is also included. Lastly, the overall structure of the book is described.

This chapter reviews neutron detection methods used in terrestrial and space environments where neutrons and protons coexist. The experimental procedures using various neutron detectors in Japan, U.S.A. and Europe are described along with the experimental results. The altitude and latitude variations of the experimental results with solar modulation are discussed and compared with calculations.

Methods and equipment to measure neutron soft-errors in a terrestrial field are described. The chi-square method used to estimate the soft-error rate (SER) is described. Correction methods used to normalize SER rates are also introduced.

This chapter reviews the properties and utilization of neutron facilities available for neutron irradiation tests of semiconductor microelectronics devices. The neutron facilities listed in JESD89-Rev (http://www.seutest.co, revised version of JESD89 Standard.JESD89A) that are available for semiconductor irradiation tests are described.

By using (quasi-) monoenergetic and spallation neutron beam facilities, a general test method is described herein. The relevant analyses techniques, including tail correction methods, Weibull-fitting, unfolding, and multi-cell upset (MCU) characterization, are also described with a variety of measured data. The authors' framework on SECIS (Self Consistent Integrated System for neutron-induced single event) is introduced.

A Monte-Carlo simulation model, which is implemented in the program packages CORIMS/SEALER, is described over the entire physical process related to neutron soft-errors. The model can be applied to any nucleon (neutron/proton) radiation fields, including accelerator and terrestrial radiation fields.

The model is validated with terrestrial field and accelerator test results. Unique results are given for asymmetrical multi-cell upset, material effects in the components, and threshold energies using realistic 3D device models.

The most recent developments with respect to the international standardization of testing methods are introduced, covering JESD89A, 89-1, 89-3, and EDR4705 (Japanese guidelines).

This chapter briefly summarizes the contents of the book. The topics which are not included in this book, and items left for action in the future, are also discussed.

The following sections are included:

• APPENDICES
  • Radiological Protection Quantities
  • Approximation Functions for Total Cross Section
  • Approximation Functions for Non-elastic Cross Section
  • Comparison of GEM Calculation Results for Inverse Reaction Cross Section with Literature Data
  • LET Approximation Results in Substrate Used for Silicon Devices
  • Coefficients for LET Calculation for Substrate Used in Silicon Devices

• REFERENCES

• TERMS AND DEFINITIONS

• INDEX