The inspection equipment technology for micro LED (ultra-small light-emitting diode) elements, which are considered key components of next-generation displays, is being promoted as an international standard.

The Ministry of Trade, Industry and Energy's National Institute of Standards and Technology (President Jin Jong-wook) proposed this standard at the International Standards Conference on Semiconductor Devices (IEC TC47) held in Jeju from May 22 to May 24.

About 50 semiconductor experts from four countries, Korea, China, Japan, and Germany, participated in this meeting.

Recently, our country has been leading the development of international standards for neuromorphic semiconductors for artificial intelligence, system semiconductor process component inspection equipment, etc., and at this meeting, a new quality evaluation method for micro LED devices for displays was proposed.

Micro LED is an inorganic light-emitting element that has a longer lifespan than OLED, an organic light-emitting element based on carbon compounds, and is attracting attention as a next-generation display because it does not have a burn-in phenomenon that leaves an afterimage on the screen.

Micro LED displays are manufactured by attaching tens to hundreds of millions of LED elements that are 1 to 20 micrometers (㎛) in size, thinner than the width of a human hair (average 100㎛). Since each LED becomes a component of a pixel and controls color and light on its own, securing LED elements of consistent quality is key.

The proposed standard is a non-contact micro LED device product using photoluminescence measurement method.It is a quality inspection method. The photoluminescence measurement method is a non-contact method that analyzes and inspects the light that the LED element emits when it receives light energy from a laser or the like, as if it were connected to a power source. It is expected that the cost of quality inspection of micro LED elements can be reduced by more than 50% because it can quickly and economically check for defects compared to the existing contact method of connecting the power source.

This proposal was promoted by utilizing the micro LED inspection equipment technology of domestic small and medium-sized enterprises as part of the KATS' 'National Standardization Strategy for Advanced Industries'.

Oh Gwang-hae, director of the Standards Policy Bureau at the Korea Agency for Technology and Standards, said, “Next-generation displays utilizing micro LED elements are expected to have significant growth as they are currently on the verge of full-scale commercialization,” and added, “We will actively support our country’s companies so that their equipment technology can become international standards and serve as a global reference.”