Vertically Phase Separated Photomultiplication Organic Photodetectors with p‐n Heterojunction Type Ultrafast Dynamic Characteristics

• DOI: 10.1002/adma.202404597
• Publication Date: 2024-07-08T14:58:19Z
• Authors: Myeong In Kim; Soonyong Lee; Jinhyeon Kang; Jaehyeong Kim; Ziang Wu; Jong Ho Won; Seyeon Baek; Dae Sung Chung; Jin Young Kim; In Hwan Jung; Han Young Woo
• Keywords: Quantum Efficiency; Active layer

Abstract Photomultiplication (PM)‐type organic photodetectors (OPDs), which typically form a homogeneous distribution (HD) of n ‐type dopants in p polymer host (HD PM‐type OPDs), have achieved breakthrough device responsivity by surpassing theoretical limit external quantum efficiency (EQE). However, they face limitations higher dark current and slower dynamic characteristics compared to p‐n heterojunction ( HJ) OPDs due inherent long lifetime trapped electrons. To overcome this, new OPD is developed that demonstrates ultrafast properties through vertical phase separation (VPS) strategy between the acceptor, referred as VPS OPDs. Notably, show three orders magnitude increase −3 dB cut‐off frequency (120 kHz) over 200‐fold faster response time (rising = 4.8 µs, falling 8.3 µs) HD OPDs, while maintaining high EQE 1121% specific detectivity 2.53 × 10 13 Jones at −10 V. The represents groundbreaking advancement demonstrating coexistence HJ PM modes within single photoactive layer for first time. This innovative approach holds potential enhance both static