IEC 60749-17:2003

Overview

IEC 60749-17:2003 is an international standard issued by the International Electrotechnical Commission (IEC) that defines mechanical and climatic test methods for semiconductor devices, focusing specifically on neutron irradiation. This standard applies to integrated circuits and discrete semiconductor devices, providing guidelines to assess their susceptibility to degradation when exposed to neutron radiation. Primarily intended for military and space applications, the test described is destructive and critical for ensuring device reliability in harsh neutron environments.

Key Topics

• Purpose of Test: The neutron irradiation test aims to detect and quantify degradation of critical electrical parameters in semiconductor devices as a function of neutron fluence. It also verifies if devices remain within specified performance limits after exposure.

• Test Apparatus:

  • Test Instruments: Standard laboratory electronic equipment such as power supplies, digital voltmeters, and pico-ammeters are required to measure electrical parameters accurately.
  • Radiation Source: A pulsed nuclear reactor serves as the neutron radiation source.
  • Dosimetry Equipment: Utilizes fast-neutron threshold activation foils (examples: sulfur (S), iron (Fe), nickel (Ni)) and thermoluminescence dosimeters (TLDs) made from CaF₂ to monitor neutron fluence and gamma dose exposure.
  • Dosimetry Measurements: Fluence is calculated by measuring induced radioactivity in activation foils, requiring knowledge of the neutron energy spectrum. If unknown, standards or methods from recognized national bodies must be employed.

• Test Procedure:

  • Safety: Handling irradiated devices requires strict safety protocols due to potential radioactivity.
  • Sample Selection: Testing involves randomly selecting at least 10 devices that meet all applicable specifications.
  • Pre-Exposure Testing: Electrical measurements are performed prior to irradiation to record baseline device parameters.
  • Exposure Setup: Devices must be mounted without bias; MOS devices require all terminals shorted. The setup accommodates dosimeters and ensures neutron fluence variation across samples does not exceed 20%.
  • Determination of Fluence: Reactor facility personnel determine positioning and pulse levels needed to achieve specified neutron fluence.

Applications

• Military Electronics: Ensuring that semiconductor components maintain functionality under neutron bombardment encountered in defense systems.

• Space Industry: Validating integrated circuits and discrete semiconductor devices for exposure to high neutron fluxes in space environments, safeguarding satellite and spacecraft electronics.

• Reliability Testing: Providing a protocol for manufacturers of semiconductors to evaluate neutron tolerance, optimize design, and improve product longevity in radiation-prone environments.

Related Standards

• IEC 60034 Series: Covers electrical machinery but provides numbering context for IEC documents such as IEC 60749 series.

• ISO/IEC Directives, Part 2: Governs the drafting and maintenance of IEC standards ensuring international consensus.

• Military and Aerospace Quality Standards: While IEC 60749-17 addresses neutron irradiation testing, related military and aerospace standards may complement it to cover broader environmental stress testing.

Keywords: IEC 60749-17, neutron irradiation test, semiconductor device testing, neutron fluence, radiation susceptibility, integrated circuits, discrete semiconductors, military electronics, space applications, neutron radiation standards, dosimetry, pulsed reactor testing