IEC 62047-35:2019

Overview

IEC 62047-35:2019 defines the standardized test method for evaluating the electrical characteristics of flexible micro-electromechanical devices (MEMS) under bending deformation. Developed by the International Electrotechnical Commission (IEC), this standard is essential for manufacturers and users of flexible semiconductor devices, covering both passive and active micro components mounted on or embedded in flexible films.

The standard enables consistent testing of device performance during mechanical bending, which is crucial for determining durability, reliability, and safety margins. Reliable data from such tests inform product design decisions for foldable, flexible, and wearable electronics in applications where mechanical stress is an operational factor.

Key Topics

• Flexible MEMS and Semiconductor Devices: Guidance applies to devices whose in-plane dimensions typically range from 1 mm to 300 mm and thickness from 10 µm to 1 mm.
• Bending Test Methodology:
  • Devices are bent in a controlled, quasi-static process up to the maximum possible curvature, simulating complete folding.
  • The entire degradation behavior of electrical properties, such as voltage, current, or resistance, is monitored throughout bending.
• Test Apparatus and Procedures:
  • Use of parallel, flat walls to gradually fold the sample until no further curvature is possible.
  • Measurements should be accurate to within specified tolerances, accounting for device geometry and non-uniformity in thickness.
• Critical Parameters:
  • Folding distance: The controlled separation between the loading walls, serving as an operational measure of mechanical stress.
  • Bending axis and direction: Tests are to be conducted along at least two orthogonal axes to investigate all potential failure modes.
  • Device dimensions: Especially the length, which significantly affects the deformation mechanics and results.
• Reporting Requirements:
  • Test reports must specify bending directions, axis locations, device dimensions, performance degradation with respect to folding distance, and detailed testing conditions.

Applications

• Wearable Electronics: Fitness trackers, medical patches, and smart textiles where flexible or foldable MEMS components are bent during normal use.
• Flexible Displays and Foldable Devices: Smartphones, tablets, and e-paper whose screens and internal circuits must retain performance after repeated bending.
• Smart Sensors: Devices such as flexible temperature sensors and bio-monitoring patches that rely on robust micro-components attached to pliable substrates.
• Organic and Printed Electronics: Thin film transistors, organic LEDs, and flexible circuits, all of which require proven endurance against mechanical deformation.
• Product Design & Quality Assurance: By applying this standard, engineers and product developers can define safety margins and predict wear-out or failure, ensuring consumer safety and product longevity.

Related Standards

When working with flexible electromechanical devices and assessing their behavior under mechanical stress, consider referencing:

• IEC 62047 series: Other parts address additional micro-electromechanical device test methods.
• IEC 60747: For general semiconductor device testing.
• IEC Electropedia (IEV): For standardized electrotechnical terminology.
• ISO/IEC 17025: For laboratory competence in performing reliable mechanical and electrical tests.

Practical Value

Adhering to IEC 62047-35:2019 ensures that manufacturers, researchers, and quality assurance professionals:

• Implement uniform and repeatable test methods for flexible semiconductor devices.
• Acquire reliable data on performance degradation due to bending deformation.
• Make informed decisions for the reliable design and deployment of foldable and flexible electronic products.
• Communicate test results effectively using clear and internationally recognized reporting guidelines.

Complying with this standard is vital for developing robust, durable, and high-performing flexible MEMS devices in today’s fast-evolving electronics market.