News: LEDs
20 August 2021
Seoul Viosys and UCSB’s SSLEEC tackle micro-LED efficiency challenges for display applications
LED product maker Seoul Viosys Co Ltd (a subsidiary of South Korea’s Seoul Semiconductor) and the Solid State Lighting & Energy Electronics Center (SSLEEC) led by Nobel Prize-winning physics professor Shuji Nakamura of University of California Santa Barbara (UCSB) say that they have developed blue and green micro-LEDs with a diameter of 1μm and addressed issues related to red micro-LEDs of less than 70μm, which previously could not be mass produced due to a drop in external quantum efficiency (EQE).
Targeting the display industry, Seoul Viosys has begun mass production of products (MC04, MC02) employing 70μm red micro-LEDs, and is preparing to release 30μm one-pixel micro-LED products in second-half 2021 and 10μm one-pixel micro-LED products in 2022.
Picture: (a) Electroluminescence (EL) wavelength spectrum of red micro-LED and (b) blue and green micro-LEDs with a diameter of 1μm viewed under an electron microscope.
Seoul Viosys says that for 20 years it has supported the SSLEEC team in the development of micro-LEDs with a diameter of 1μm and made it possible to produce ultra-small micro-LED solutions and to improve brightness through a 150% increase in the EQE of red micro-LEDs. The application of red micro-LEDs has previously been limited due the light-emitting efficiency falling as size was reduced (Smith et al, Optics Express 5787, vol 28, no.4 (2020)/Appl. Phys. Lett. 116, 071102 (2020)).
Seoul Viosys is hence expecting rapid commercialization of display applications such as smartphones, augmented reality (AR) and virtual reality (VR) through improved micro-LED technology.
“According to our principle to supply new products first to the companies that respect intellectual property rights, we will first supply the new ultra-small-size 10μm and 30μm one-pixel micro-LEDs to the customers who have purchased our products (MC04, MC02, Wicop MINI, etc) and are using them,” states Seoul Viosys.
Reference: TrendForce, a Taiwanese market research institute, forecasts that the annual sales of micro-LED chips for TVs will increase to an annual average of 250% from 2021 to 2025. It expected that the size of the market, which was only US$23m in 2021, will increase 150 times in just five years.
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