ISO 23038:2018

Overview

ISO 23038:2018 – Space Systems - Space Solar Cells - Electron and Proton Irradiation Test Methods is an internationally recognized standard developed by the International Organization for Standardization (ISO). This document outlines standardized procedures for testing the effects of electron and proton radiation on space solar cells, which are critical components in spacecraft power systems. ISO 23038:2018 defines the requirements for irradiation test methods, ensuring consistency, reliability, and repeatability in evaluating solar cell performance under simulated space radiation environments. Notably, it addresses only the test procedures for irradiation and does not prescribe data analysis methodologies.

Key Topics

• Space Radiation Environment:
  The standard describes the typical radiation environment encountered in space, mainly consisting of energetic electrons and protons, and the impact of phenomena such as solar flares and the Van Allen radiation belts.

• Radiation Effects on Solar Cells:
  Solar cells are vulnerable to degradation due to displacement and ionization damage caused by particle irradiation. ISO 23038:2018 specifies test approaches to simulate these effects under controlled laboratory conditions.

• Test Methodology:

  • Electron irradiation: Procedures for exposing solar cells to electron beams, considering factors like vacuum conditions, temperature control, beam coverage, uniformity, and flux measurement.
  • Proton irradiation: Special considerations for proton exposure due to greater scattering in air, with recommendations for vacuum conditions and material selection for scattering foils.
  • Beam Dosimetry: Techniques for measuring irradiation fluence, including Faraday cup usage and secondary dosimetry methods.
  • Test Sample Handling: Guidance on sample preparation, coverage area, exposure methodologies, and handling to ensure accurate and representative results.

• Test Report Requirements:
  The standard provides a checklist for documentation, including sample details, irradiation and annealing conditions, measurement methods, and uncertainty levels to ensure traceability and reproducibility.

Applications

ISO 23038:2018 supports organizations involved in the design, production, and qualification of space solar cells, including:

• Satellite manufacturers needing to validate solar cell durability and performance before assembly.
• Space agencies and research groups conducting irradiation studies to predict long-term degradation of solar power systems in different mission profiles.
• Component suppliers seeking to demonstrate compliance with international qualification requirements by applying standardized irradiation testing methods.
• Testing laboratories performing irradiation services and generating accredited test reports in line with recognized methodologies.

By following the procedures established in ISO 23038:2018, stakeholders can ensure solar cell reliability under real-world space conditions, minimize mission risk, and facilitate technology selection for specific orbits and mission durations.

Related Standards

For comprehensive qualification of space solar cells and components, the following international standards and resources provide complementary guidance:

• ISO/IEC standards on space system design and radiation environments
• JPL Solar Cell Radiation Handbooks (Silicon and GaAs)
• SRIM, CASINO, MCNPX, and GEANT4 – simulation tools referenced for irradiation transport calculations
• Other ISO/TC 20/SC 14 standards covering space system performance and environmental effects.

Implementing ISO 23038:2018 alongside related standards ensures robust and internationally recognized approaches to space solar cell qualification, strengthening mission assurance and supporting global collaboration in the aerospace industry.