Guidelines for the Determination of Standardized Semiconductor Radiation Hardness Parameters

Electronic devices containing semiconductor materials are used in harsh radiation environments in many fields of research and technology. High energy physics facilities, remote control systems in nuclear reactors, radiotherapy facilities and the aerospace sector are among the most significant areas where electronic devices are exposed to high levels of detrimental ionizing radiation. The long term operating performance, reliability and lifetime of these electronic materials and devices are strictly related to their resistance to various types and levels of ionizing radiation, which induces a progressive degradation of their performance. The evaluation of the materials’ radiation hardness (i.e. their resistance to accumulated damage caused by ionizing radiation) is crucial for the effective design of electronic devices. Therefore, reliable and widely applicable test methodologies suitable for determining radiation hardness (i.e. the measure of the non-vulnerability or of the resistance of the material to an accumulated level of radiation damage in a variety of experimental conditions) are needed to facilitate the optimal synthesis of materials for the design of electronic devices. Ion accelerator based techniques provide insight into the phenomena underlying the formation of defects induced by energetic particles in semiconductor materials and their effects on the electronic features of the device. Because of the potential of these techniques, the IAEA implemented a coordinated research project from 2011 to 2016 entitled ‘Utilization of Ion Accelerators for Studying and Modelling of Radiation Induced Defects in Semiconductors and Insulators’ to investigate the mechanisms underlying the performance degradation of semiconductor devices induced by ionizing radiation. The objective of the project was to use accelerator based ion irradiation and analytical techniques to gain a deeper understanding of how different types of radiation influence the electronic properties of materials and devices, leading to an improved knowledge of radiation hardness and to the engineering of ‘radiation harder’ devices. Research stimulated by the project resulted in publications in scientific journals, educational and scientific software packages, and a number of new collaborations among the participating research groups. The most significant outcomes of this project were the development of a protocol for existing experimental characterization techniques used to investigate radiation effects in semiconductor devices and the development of a relevant theoretical approach to interpret the experimental data. This publication provides comprehensive guidelines for the assessment of the radiation hardness of semiconductor devices, including a detailed description of the experimental procedures, the theoretical model and the limits of its application, and data analysis techniques. The intended audience includes professionals and technologists who wish to apply standardized practices in ion beam functional analysis of semiconductor materials. Solid state physicists and engineers involved in the design of electronic devices for use in harsh radiation environments might also benefit from using the theoretical model to obtain better predictions of the operating performance and lifetime of such devices. The IAEA is grateful to E. Vittone of the University of Torino and all the other experts who contributed to this publication. The IAEA officer responsible for this publication was A. Simon of the Division of Physical and Chemical Sciences.