Lateral PIN (p-MoTe₂/Intrinsic-MoTe₂/n-MoTe₂) Homojunction Photodiodes

Abstract

The construction of high-speed electronic devices that can be integrated using a single two-dimensional (2D) semiconductor with high performance remains challenging due to the absence of locally selective doping methods. In this study, we have demonstrated that the selective opposite polarities (p-type or n-type) from an intrinsic 2H-MoTe2 field-effect transistor (FET) can be configured through carrier type band modulation in molybdenum ditelluride (MoTe2) caused by the charge storage interface in MoTe2/BN vdW heterostructures upon UV illumination with electrostatic gate bias. With this approach, we demonstrate a lateral p-i-n homojunction diode (p-MoTe2/intrinsic-MoTe2/n-MoTe2) using a single two-dimensional semiconductor (2H-MoTe2) where an intrinsic FET (i-type region) is sandwiched between p- and n-type FETs. Electrical performance of such a p-i-n diode demonstrates an ideal rectifying behavior with a rectification ratio (I f/I r) of up to ∼1.4 × 106 at zero gate bias with an ideal value of the ideality factor of nearly ∼1. To support optoelectrical doping, Kelvin probe force microscopy (KPFM) measurements are performed where p- and n-type MoTe2 channels show work function values of ∼5.0 and ∼ 4.55 eV, respectively, with a built-in potential of ∼450 mV. In the photovoltaic mode, the p-i-n diode shows excellent photodetection properties under an illumination of 600 nm, a maximum value of responsivity of 1.10 A/W, and a specific detectivity value of 3.0 × 1012 Jones. The device shows ultrafast photoresponses, where the response speed (τr/τf) is estimated to be 10/20 ns. The proposed research offers an opportunity for creating stable p-i-n homojunction diodes for high-speed electronics with low power consumption using 2D materials.

Recent advances in TMD interfaces with seamless contacts

“…4 The calculated lattice parameters are mentioned in Table 1. The 2H phase loses inversion symmetry near the K point of the Brillouin zone, which results in spin-split bands in the bulk materials, which leads to valleytronic performance [5][6][7] and could be a potential material for spintronic applications. 8 The valence band maximum and conduction band minimum lie at the different symmetry points.…”

“…Two-dimensional (2D) transition metal dichalcogenides (TMDs) can have a wide range of compositions and dual phases of crystalline and electronic structures, giving these materials a wide range of interesting properties. [1][2][3][4][5][6][7][8][9][10][11][12] The number of layers has a significant influence on the physical properties of the materials as well as defining the electrical and optical structures of 2D quantum systems due to quantum confinement and interlayer interactions. Because of their various layered structures, such as hexagonal 2H polytype to semimetal (trigonal 1T 0 polytype) phases and distorted octahedral, the number of layers has a significant impact on the physical material characteristics.…”

“…Some 2D materials, such as h-BN, cannot be used to fabricate channel materials due to the presence of band gaps and must be avoided. Even if the band gap value can be controlled using defects, 6,[13][14][15][16][17][18][19] doping, 16,[20][21][22][23] or strain engineering, 13,20,24 exact control is always an experimental and conceptual challenge. Monolayer MX 2 s have the most tunable band gaps of any 2D material discovered to date.…”

Yb/Se/WO3/Yb Thin Film Transistors as Rectifiers, N‐Channel Metal Oxide Semiconductor Capacitors, Laser Sensors, and Microwave Bandstop Filters

“…In addition, asymmetric Ti/Pt/BaTiO 3 /CeO 3 /Au heterostructures are mentioned performing as rectifiers, resistive switches, and negative differential resistance sources. [35] Other device structures [36][37][38][39] that are listed in Table 2 show similar interesting functionalities. The tabulated class of devices indicated that our proposed back-to-back Schottky device reached an additional functionality presented by microwave filtering which makes it suitable as microwave resonators.…”

Elucidating the roles of oxygen functional groups and defect density of electrochemically exfoliated GO on the kinetic parameters towards furazolidone detection

“…Over the last decade, two-dimensional nanomaterials such as molybdenum disulfide (MoS 2 ), two-dimensional transition metal dichalcogenides (TMDs), and graphene oxide (GO) with their unique physicochemical properties have been used as nanoplatforms in electrochemical sensors 3,7–9 . Among them, GO is one of the common 2D nanomaterials to select for modification of the electrode surface due to its large surface area, good conductivity, chemical stability, and strong mechanical strength.…”