High Performance and Bendable Few-Layered InSe Photodetectors with Broad Spectral Response

Abstract

Two-dimensional crystals with a wealth of exotic dimensional-dependent properties are promising candidates for next-generation ultrathin and flexible optoelectronic devices. For the first time, we demonstrate that few-layered InSe photodetectors, fabricated on both a rigid SiO2/Si substrate and a flexible polyethylene terephthalate (PET) film, are capable of conducting broadband photodetection from the visible to near-infrared region (450-785 nm) with high photoresponsivities of up to 12.3 AW(-1) at 450 nm (on SiO2/Si) and 3.9 AW(-1) at 633 nm (on PET). These photoresponsivities are superior to those of other recently reported two-dimensional (2D) crystal-based (graphene, MoS2, GaS, and GaSe) photodetectors. The InSe devices fabricated on rigid SiO2/Si substrates possess a response time of ∼50 ms and exhibit long-term stability in photoswitching. These InSe devices can also operate on a flexible substrate with or without bending and reveal comparable performance to those devices on SiO2/Si. With these excellent optoelectronic merits, we envision that the nanoscale InSe layers will not only find applications in flexible optoelectronics but also act as an active component to configure versatile 2D heterostructure devices.

Booming Development of Group IV–VI Semiconductors: Fresh Blood of 2D Family

“…and group III–VI nanomaterials (InSe,38, 39, 40, 41, 42 GaSe,43, 44, 45, 46, 47, 48 etc.) have been extensively investigated in many fields including photodetectors,49, 50, 51, 52, 53, 54, 55, 56, 57, 58 gas sensors,59, 60 field effect transistors (FETs),38, 61, 62, 63, 64, 65 and flexible devices 66, 67, 68…”

Ternary CuIn7Se11: Towards Ultra‐Thin Layered Photodetectors and Photovoltaic Devices

“…Recently, InSe was reported to have a smaller band gap of 1.4 eV, making it appropriate for the near infrared (NIR) range. [18] But for photovoltaics and photodetectors, especially IR photodetectors, an even smaller band gap would be desirable to expand the spectral range of the response even further.…”

Inversion Domain Boundary Induced Stacking and Bandstructure Diversity in Bilayer MoSe2

“…Van der Waals (vdW) epitaxy of two-dimensional (2D) layers has been demonstrated a marvelous route to build 2D nanostructures functionalized as transistors [1][2][3][4][5][6] , photo detectors [7][8][9][10][11] , light absorbers 6,12 , memories 13,14 , switchers 15 and other electronic and optoelectronic devices 16,17 . Interlayer interaction plays a dominant role in determining physical properties of these nanostructures.…”