Overview
IEC 60747-5-9:2019 defines the standardized test method for measuring the internal quantum efficiency (IQE) of single light emitting diode (LED) chips or packages without phosphor. Developed by the International Electrotechnical Commission (IEC), this standard is crucial for accurately characterizing optoelectronic devices by evaluating IQE using temperature-dependent electroluminescence (TDEL). The method is not applicable to white LEDs used for general lighting but focuses on other types of LEDs, supporting quality control and development in the semiconductor industry.
The standard outlines the process for determining IQE by comparing external quantum efficiencies (EQEs) at cryogenic and operating temperatures, establishing rigorous environmental and measurement controls. By supporting accurate IQE assessment, IEC 60747-5-9:2019 enables effective benchmarking for semiconductor LED performance.
Key Topics
- Internal Quantum Efficiency (IQE): Definition and relevance for LED performance. IQE is the ratio of photons emitted from the LED's active region to the number of electrons injected.
- External Quantum Efficiency (EQE): Measurement as a function of temperature and injection current, forming the basis for assessing IQE.
- Temperature-Dependent Electroluminescence (TDEL): Methodology using relative EQEs measured at both cryogenic and operating temperatures to identify conditions with maximal efficiency.
- Measurement Conditions: Strict procedures for temperature (including cryogenic setups), humidity, current injection, and thermal equilibrium to ensure repeatable results.
- Validity Criteria: Determination of whether the IQE can be accurately measured based on specific criteria-only when certain saturation and consistency thresholds are met under cryogenic condition.
- Reporting Requirements: Structure and content for comprehensive test reports, promoting transparency and reproducibility.
Applications
IEC 60747-5-9:2019 is widely applicable in sectors leveraging advanced LED technologies:
- Research and Development: Enables precise evaluation of efficiency in the early stages of LED design, supporting optimization of semiconductor materials and structures.
- Quality Assurance: Assists manufacturers in verifying the quality and efficiency of LED chips and packages, ensuring that only high-performing products reach the market.
- Performance Benchmarking: Facilitates comparison between different LED designs by providing a reliable and repeatable measurement technique for IQE.
- Device Validation: Useful in verifying device performance over different operating and environmental conditions, aiding in failure analysis and improvement cycles.
- Supply Chain Communication: Provides a standardized framework for efficiency data exchange between producers, integrators, and end-users in the optoelectronics industry.
Related Standards
- IEC 60747-5-6:2016 – Semiconductor devices – Part 5-6: Optoelectronic devices – Light emitting diodes (outlining measurement methods for basic optoelectronic properties)
- IEC 60747-5-8:2019 – Semiconductor devices – Part 5-8: Light emitting diodes – Test method of optoelectronic efficiencies
- IEC 60050-845 – International Electrotechnical Vocabulary – Lighting (for standardized terminology)
- Further IEC 60747 series standards for various semiconductor device test methods
Practical Value
Adopting IEC 60747-5-9:2019 promotes uniform, reliable measurement practices within the global LED industry. The standard:
- Supports higher product quality and consistency through standardized IQE measurement.
- Enables informed decision-making for both manufacturers and customers by providing credible, comparable efficiency data.
- Facilitates innovation in LED technology by setting clear benchmarks for research and development.
- Reduces ambiguity in technical communications across the LED and semiconductor value chain.
- Underpins regulatory and certification processes by providing a documented methodology for assessing critical efficiency parameters.
For engineers, researchers, and quality managers in the LED and optoelectronics sector, compliance with IEC 60747-5-9:2019 is essential for ensuring accurate efficiency evaluation and supporting product excellence.
Open preview (PDF)Semiconductor devices - Part 5-9: Optoelectronic devices - Light emitting diodes - Test method of the internal quantum efficiency based on the temperature-dependent electroluminescence
