POS5-0067
Rational Molecular Design of π-Extended Thiazolothiazole for High-Performance UV-OPDs Seamlessly Integrated with CMOS
When and Where
Nov 30, -0001
00:00 - 00:00
Presenter(s)
Won Jun Pyo (Pohang University of Science and Technology)
Co-Author(s)
Abstract
Vacuum-deposited organic photodiodes (OPDs) offer unique advantages—including narrowband selectivity and compatibility with standard fabrication processes—but achieving ultraviolet (UV) selectivity in such devices remains a key challenge. This is due to the need to reconcile two competing design requirements: (1) strong π–π stacking for efficient charge transport, and (2) limited π-conjugation to retain a wide bandgap suitable for UV absorption and vacuum deposition. Here, we report a molecular design strategy for UV-selective OPDs based on thiazolothiazole (Tz)-based small molecules with tailored backbone planarity and conjugation length. The resulting vacuum-deposited active layers simultaneously exhibit wide bandgaps and robust π–π interactions. The optimized devices achieve outstanding UV selectivity (full-width at half-maximum: 60 nm), high specific detectivity (1.06 × 10¹² Jones), and fast dynamic response (cutoff frequency of 50,100 Hz)—representing the highest performance for vacuum-deposited UV-OPDs reported to date. Furthermore, we demonstrate the seamless integration of these semi-transparent OPDs with CMOS image sensors, underscoring their potential for multifunctional imaging applications. Our findings provide key molecular insights for advancing UV-selective organic photodetectors.
