Choi, Hyung Jin Jung, Byung Ku Choi, Young Kyun Hong, Yun-Kun Lee, Yong Min Park, Taesung Jo, Hyunwoo Kang, Moon Sung Jang, Ho Seong Zhao, Tianshuo Oh, Soong Ju 2024-11-07T01:00:09Z 2024-11-07T01:00:09Z 2024-11-06 2024-11 1385-8947 https://pubs.kist.re.kr/handle/201004/150964 Indium Arsenide (InAs) colloidal quantum dots (CQDs) are emerging candidates for infrared photodetector applications owing to their excellent optoelectronic properties and low toxicity. However, low electron mobility stemming from its unique surface chemistry hinders its practical application. Through comprehensive structural and chemical analyses, we optimized the one-step HCl treatment to achieve stoichiometric balance, a wellpassivated surface with low defect density, and an improved coupling effect by reducing the interparticle distance. Subsequently, a near infrared photodetector at a wavelength of 980 nm was fabricated with the modified InAs QDs in thin film transistor structure by all-solution process, showing remarkable electron mobility enhancement of up to 3.15 cm2/V center dot s. The thin film phototransistor exhibited excellent photoresponse with a responsivity of 5.45 x 103 A/W, external quantum efficiency of 6.90 x 105%, and a linear dynamic range of 50 dB. This achievement represents the highest responsivity observed in an InAs QD-based phototransistor device, demonstrating its potential for lead-free infrared (IR) region optoelectronic applications. English Elsevier BV Hydrogen chloride treated InAs quantum dot thin film phototransistor for ultrahigh responsivity Article 10.1016/j.cej.2024.156191 1 Chemical Engineering Journal, v.499 Chemical Engineering Journal 499 N scie scopus 001336662500001 2-s2.0-85206132171 Engineering, Environmental Engineering, Chemical Engineering Article TRANSISTORS NANOCRYSTALS MOBILITY InAs quantum dot Ligand exchange Etching Phototransistor Electron mobility