Surmounting the interband threshold limit by the hot electron excitation of multi-metallic plasmonic AgAuCu NPs for UV photodetector application. Issue 22 (25th May 2022)

• Record Type: Journal Article
• Authors: Lin, Shusen; Kulkarni, Rakesh; Mandavkar, Rutuja; Habib, Md Ahasan; Burse, Shalmali; Kunwar, Sundar; Lee, Jihoon
• Is Part Of: CrystEngComm. Volume 24:Issue 22(2022)
• Page Start: 4134
• Page End: 4143
• Publication Date: 2022-05-25
• Subjects: Crystals -- Periodicals; Crystal growth -- Periodicals; Crystallography -- Periodicals; Cristaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Cristallographie -- Périodiques; 548
• DOI: 10.1039/d2ce00367h
• Languages: English
• ISSNs: 1466-8033

Abstract

Abstract : Sharply improved photoresponse characteristics are demonstrated by the multi-metallic AgCu, AuCu and AgAuCu NP based UV-PDs through the superior photo carrier injection by the strong elemental composition-dependent hot electrons and localized surface plasmon resonance (LSPR). Abstract : Multi-metallic alloy NPs composed of various elemental compositions can surmount the interband threshold limit of mono-metallic NPs and thus can offer a promising route to boost up the performance limit of conventional ultraviolet photodetectors (PDs). In this work, a hybrid UV-PD configuration has been demonstrated by combining the multi-metallic plasmonic alloy NPs of AgCu, AuCu, and AgAuCu on a GaN photoactive layer in order to exploit the improved photo carrier injection by the strong hot electrons and LSPR. Among various devices, the tri-metallic AgAuCu NP PD demonstrates the highest performance with a remarkably high photocurrent of 1.47 × 10 −2 A at 1 V with fast rise ( T r ) and fall ( T f ) times of 170 and 700 ms with a very stable current. This leads to the superior figure-of-merit parameters of the PD with a photoresponsivity of 4.3 × 10 6 mA W −1, detectivity of 3.52 × 10 12 Jones and EQE of 1.39 × 10 6 %, which is ∼16 times higher than the bare GaN PD. This ranks the AgAuCu PD as one of the best GaN based UV photodetectors. The photocurrent enhancement and excellent figure-of-merit can be attributed to the significantly increased photo carrier injection by the efficient hot electron generation via the LSPR and improved interfacial barrier characteristics by the tri-metallic elemental synergy.