Solvent-Assisted Transfer-Printing of Silver Electrodes for High-Performance Organic Photodetectors

Organic photodetectors (OPDs) have garnered significant attention due to their low cost, flexibility, and simple manufacturing process. In this work, we conducted a systematic study of different transfer-printing parameters with the aid of residual solvents. We found that the amount of residual solvent and heating time during transfer-printing were critical for successful fabrication. The results showed that compared to OPDs fabricated by vacuum evaporation, transfer-printed OPDs exhibited a reduction in dark current by approximately 1 order of magnitude while maintaining a comparable photocurrent. Transfer-printed OPDs also showed higher responsivity, specific detectivity, and a wider linear dynamic range. The impact of transfer-printing on the interface is investigated using electron-only devices, revealing that the transfer-printing process improved the interface between the Ag electrode and electron transport layer and resulted in a higher charge carrier drift mobility and lower total trap density. A flexible OPD using the transfer-printing process is also demonstrated. This work presents a novel technique that is expected to play a role in the transfer-printing of OPDs.