Achieving Bright Organic Light-Emitting Field-Effect Transistors with Sustained Efficiency through Hybrid Contact Design

作者：Chiu, Shih-Wei; Hsu, An; Ying, Lei; Liaw, Yong-Kang; Lin, Kun-Ta; Ruan, Jrjeng; Samuel, Ifor D. W.; Hsu, Ben B. Y.^*

来源：ACS applied materials & interfaces, 2023, 15(25): 30524-30533.

DOI：10.1021/acsami.3c01842

• light-emittingtransistors
• low efficiency roll-off
• high brightness
• semiconducting conjugated polyelectrolytes
• band bending

Organiclight-emitting field-effect transistors (OLEFETs) withbilayer structures have been widely studied due to their potentialto integrate high-mobility organic transistors and efficient organiclight-emitting diodes. However, these devices face a major challengeof imbalance charge transport, leading to a severe efficiency roll-offat high brightness. Here, we propose a solution to this challengeby introducing a transparent organic/inorganic hybrid contact withspecially designed electronic structures. Our design aims to steadilyaccumulate the electrons injected into the emissive polymer, allowingthe light-emitting interface to effectively capture more holes evenwhen the hole current increases. Our numerical simulations show thatthe capture efficiency of these steady electrons will dominate chargerecombination and lead to a sustained external quantum efficiencyof 0.23% over 3 orders of magnitude of brightness (4 to 7700 cd/m(2)) and current density (1.2 to 2700 mA/cm(2)) from-4 to -100 V. The same enhancement is retained evenafter increasing the external quantum efficiency (EQE) to 0.51%. Thehigh and tunable brightness with stable efficiency offered by hybrid-contactOLEFETs makes them ideal light-emitting devices for various applications.These devices have the potential to revolutionize the field of organicelectronics by overcoming the fundamental challenge of imbalance chargetransport.