tant IV. Proton Effects and Test Issues for Satellite Designers Part B: Displacement Effects Cheryl J. Marshall NASA/Goddard Space Flight Center Electrical Systems Center / Code 562 Greenbelt, Maryland 20771 Paul W. Marshall Consultant 7655 Hat Creek Road Brookneal, VA 24528 1.0 Introduction 2.0 Proton Induced Displacement Damage Mechanisms and Tools 2.1 Displacement Damage Mechanisms and Defect Formation 2.2 Displacement Damage Effects in Materials and Devices 2.3 Non-Ionizing Energy Loss Rate (NIEL) Concept 2.3.1 The Correlation of NIEL to Device Behavior 2.3.2 Limitations in the Use of NIEL 2.3.3 Calculation of Displacement Damage Equivalent Fluences 2.3.4 Concept of "Displacement Damage Dose" 2.4 On-Orbit Performance Predictions 3.0 Proton Displacement Damage Case Studies 3.1 Introduction 3.2 Laboratory Radiation Test Issues 3.3 Case Studies 3.3.1 Bipolar Transistors 3.3.2 Charge Transfer Devices 3.3.3 Photodetectors 3.3.4 Lasers and Light Emitting Diodes 3.3.5 Optocouplers 3.3.6 Solar Cells 4.0 Summary 5.0 Acknowledgments 6.0 References IV-50 1.0 INTRODUCTION Microelectronic and photonic systems in the natural space environment are bombarded by a variety of charged particles including electrons, trapped protons, cosmic rays, and solar particles (protons and other heavy ions). These incident particles cause both ionizing and non-ionizing effects when traversing a device, and the effects can be either transient or permanent. The vast majority of the kinetic energy of an incident proton is lost to ionization, creating the single event effects (SEEs) and total ionizing dose (TID) effects described in section IVA. However, the small portion of energy lost in non-ionizing processes causes atoms to be removed from their lattice sites and form permanent electrically active defects in semiconductor materials. These defects, i.e., "displacement damage," can significantly degrade device performance. In general, most of the displacement damage effects in the natural space environment can be attributed to protons since t