IEC 62047-37:2020

Overview

IEC 62047-37:2020 is an international standard developed by the International Electrotechnical Commission (IEC) focusing on environmental test methods for MEMS piezoelectric thin films used in sensor applications. This standard is part 37 of the IEC 62047 series covering semiconductor devices and micro-electromechanical systems (MEMS). It provides standardized procedures to assess the durability and quality of MEMS piezoelectric thin films, specifically under environmental stresses such as temperature, humidity, mechanical stress, and applied voltage. These thin films are primarily utilized in acoustic sensors and cantilever-type sensors based on silicon substrates.

The standard plays a vital role in ensuring the performance stability of piezoelectric MEMS devices by defining test protocols that help manufacturers and researchers evaluate the impact of environmental factors on piezoelectric properties. It complements IEC 62047-30, which addresses measurement methods for the electro-mechanical characteristics of MEMS piezoelectric thin films.

Key Topics

• Durability Testing Under Environmental Stress
  IEC 62047-37 specifies tests that subject devices under test (DUTs) to high/low temperature cycles, humidity conditions, mechanical strain, and electrically induced stress. The standard includes:

  • High-temperature bias tests
  • High-temperature and high-humidity bias tests
  • Temperature cycling tests
  • Soldering heat tests simulating real manufacturing and operational environments

• Measurement of Piezoelectric Properties
  The assessment framework involves measuring piezoelectric parameters before and after environmental stress exposure, based on methods outlined in IEC 62047-30. This ensures changes in direct piezoelectric characteristics are accurately tracked.

• Test Conditions and Setup
  The document outlines detailed procedures for setting up DUTs, defining test durations, number of devices to test, and environmental chamber configurations. It also includes specifications for:

  • Temperature and humidity ranges
  • Applied voltage levels during bias testing
  • Dielectric withstand testing circuits

• Quality Assessment, Not Reliability Projection
  IEC 62047-37 focuses on immediate durability and quality evaluation rather than long-term lifetime predictions or reliability distributions such as Weibull analysis.

Applications

IEC 62047-37:2020 is critical for any organization involved in the development, manufacturing, or quality assurance of MEMS piezoelectric thin film devices used in various sensor applications:

• Acoustic Sensors
  For use in microphones, ultrasound devices, and other applications requiring sensitive acoustic detection where piezoelectric thin film stability impacts performance.

• Cantilever-Type Sensors
  In environmental sensing, biomedical devices, and mechanical detection systems where MEMS cantilevers integrated with piezoelectric films provide signal conversion.

• Semiconductor Fabrication and Assembly
  Test guidelines include heat profiles mimicking solder reflow processes, helping manufacturers ensure their devices can withstand assembly stresses.

• Quality Control in MEMS Production
  Facilitates consistent manufacturing standards by employing reproducible environmental testing relevant to operational conditions.

Related Standards

• IEC 62047-30
  Measurement methods for electro-mechanical conversion characteristics of MEMS piezoelectric thin films, which complements the environmental testing procedures of part 37.

• IEC Standards on Semiconductor Environmental Testing
  Incorporates test conditions and requirements adapted from general semiconductor device and ceramic dielectric capacitor environmental standards, ensuring cross-industry compatibility.

• Others in IEC 62047 Series
  Cover various aspects of MEMS devices and testing methods, offering a comprehensive framework for micro-electromechanical device standardization.

Summary

IEC 62047-37:2020 establishes essential environmental testing protocols for evaluating the durability of MEMS piezoelectric thin films used in sensor applications under real-world operational stresses. By providing systematic test procedures to measure piezoelectric properties after exposure to temperature, humidity, mechanical strain, and applied voltages, it ensures device reliability and quality assurance. This standard supports manufacturers, engineers, and researchers in optimizing MEMS sensor performance and robustness, facilitating innovation in acoustic and cantilever sensor technologies with confidence in their environmental endurance.