Researchers report perovskite LEDs based on MoS2 backplane TFTs

Researchers at Yonsei University and Korea University have integrated perovskite films with two-dimensional electronics to address current obstacles that hinder the commercialization of perovskite LEDs (PeLEDs). 

The scientists developed centimeter-scale integrated PeLED displays achieving key metrics on par or better than existing standards. This work suggests the potential transition of PeLEDs from lab concept to next-generation commercial displays.


Advancements in two-dimensional (2D) transition metal dichalcogenides (TMDCs) like molybdenum disulfide (MoS2) have enabled critical progress. With their atomic thickness, high charge carrier mobility, and capability for flexible low-temperature fabrication, TMDCs show potential as integrated control circuitry to drive PeLED displays.

Capitalizing on these breakthroughs, the new study from Yonsei and Korea Universities integrated PeLED pixels with MoS2 transistor arrays to create full active matrix displays with superior performance. Refinements included using single-source thermal evaporation to deposit exceptionally uniform CsPbBr3 perovskite layers across 49 cm2 areas and implementing MoS2 thin-film transistors (TFTs) as robust low-power backplanes to actively address the LED pixels.

Compared to previous small-scale demonstrations, this heterogeneous integration of emergent nanomaterials yielded 8x8 centimeter-scale displays with one millisecond response times, no visible crosstalk between pixels, and brightness control spanning three orders of magnitude. The evaporated perovskite films also showed impressive stability, with lifetimes over an hour even without encapsulation.

Remarkably, the simple single-source evaporation process achieved equivalent or better LED characteristics compared to more complex techniques, while also ensuring the film reliability necessary for electronic displays. This addresses a key manufacturing challenge that has restrained commercial progress. Enabled by these innovations, the prototypes compare favorably with existing display technologies in metrics like color purity, brightness, and switching speed.

By combining the advantages of TMDC circuits and PeLED emitters into full integrated systems, this research provides a blueprint toward next-generation displays. 

Posted: Dec 13,2023 by Roni Peleg