IEC 60749-7:2025

Overview

IEC 60749-7:2025 - "Semiconductor devices - Mechanical and climatic test methods - Part 7: Internal moisture content measurement and the analysis of other residual gases" defines a destructive internal gas analysis (IGA) method for measuring water vapour and residual gases inside metal or ceramic hermetically sealed semiconductor packages. The standard is intended as a quality and reliability check on sealing processes and to assess long‑term chemical stability of the package atmosphere. It is primarily used for high‑reliability applications such as aerospace and military electronics.

Key Topics and Requirements

• Scope: Measurement of primary sealing gases, moisture content, bombing gases (e.g. helium), oxygen/argon ratio (~20:1 ±10 %), leak‑test fluids (fluorocarbons), and other residual gases that indicate sealing quality or chemical instability.
• Destructive test: The procedure requires opening the package in vacuum and is not non‑destructive.
• Mass spectrometer (MS) requirements:
  • Spectra range: 1 AMU to 140 AMU
  • Signal‑to‑noise ratio: ≥ 20:1 for specified limits
  • Minimum detection limits: moisture 250 ppmv; N2, O2, Ar, CO2, H2, He, fluorocarbons 50 ppmv
  • Fluorocarbons identified by masses 69 and 119
• Test apparatus:
  • Vacuum opening chamber and vacuum transfer passage to avoid moisture loss by adsorption
  • Piercing arrangement (sharp‑point tool via bellows) to open packages without breaking MS vacuum
  • Temperature control verification (device temperature maintained at 100 ± 5 °C for ≥ 10 min for certain procedures)
  • Pressure sensing device for relative pressure rise measurement (for comparative gas quantity)
  • Package simulators to reproduce injection dynamics and calibrate for different internal volumes
• Calibration:
  • Detailed system and periodic calibration requirements (including quarterly checks for some gases)
  • Moisture calibration via standard generation techniques (two‑pressure, divided flow, cryogenic)
  • Dew point hygrometer accuracy ± 0.2 °C; pressure sensor accuracy ± 300 Pa
• Alignment: Rewritten to align with MIL‑STD‑883 Method 1018.10, with added calibration detail.

Applications and Users

• Who uses it:
  • Semiconductor test laboratories and IGA labs
  • Reliability and quality engineers in aerospace, defense, and medical electronics
  • Suppliers and manufacturers of hermetic semiconductor packages
• Practical uses:
  • Verifying hermeticity and sealing process quality
  • Detecting trapped leak‑test fluids (indicates IEC 60749‑8 failure)
  • Assessing package atmosphere stability for long‑term reliability predictions
  • Supporting qualification and failure analysis of high‑reliability components

Related Standards

• IEC 60749-8 - Sealing methods and leak testing (referenced for leak‑test fluid criteria)
• MIL‑STD‑883 Method 1018.10 - Alignment reference used in this edition
• Other parts of the IEC 60749 series for mechanical and climatic test methods

Keywords: IEC 60749-7, internal gas analysis, IGA, hermeticity, moisture content, mass spectrometer, semiconductor reliability, fluorocarbon, helium, calibration.