Fully Depleted Self‐Aligned Heterosandwiched Van Der Waals Photodetectors

Abstract

Room‐temperature‐operating highly sensitive mid‐wavelength infrared (MWIR) photodetectors are utilized in a large number of important applications, including night vision, communications, and optical radar. Many previous studies have demonstrated uncooled MWIR photodetectors using 2D narrow‐bandgap semiconductors. To date, most of these works have utilized atomically thin flakes, simple van der Waals (vdW) heterostructures, or atomically thin p–n junctions as absorbers, which have difficulty in meeting the requirements for state‐of‐the‐art MWIR photodetectors with a blackbody response. Here, a fully depleted self‐aligned MoS2‐BP‐MoS2 vdW heterostructure sandwiched between two electrodes is reported. This new type of photodetector exhibits competitive performance, including a high blackbody peak photoresponsivity up to 0.77 A W−1 and low noise‐equivalent power of 2.0 × 10−14 W Hz−1/2, in the MWIR region. A peak specific detectivity of 8.61 × 1010 cm Hz1/2 W−1 under blackbody radiation is achieved at room temperature in the MWIR region. Importantly, the effective detection range of the device is twice that of state‐of‐the‐art MWIR photodetectors. Furthermore, the device presents an ultrafast response of ≈4 µs both in the visible and short‐wavelength infrared bands. These results provide an ideal platform for realizing broadband and highly sensitive room‐temperature MWIR photodetectors.

Chalcogenide‐Based Narrowband Photodetectors for Imaging and Light Communication

“…In particular, the Sb 2 Se 3 ‐based CNBPDs exhibited extremely fast rising and falling times, as shown in Figure S12a (Supporting Information). Furthermore, the −3 dB cut‐off frequency ( f –3 dB ) [ 42,43 ] of the optimized Sb 2 Se 3 was determined to be >3 MHz (Figure S12b, Supporting Information), which is compelling for communications. Hence, we also evaluated these devices particularly in this regard.…”

Air-Stable Flexible Photodetector Based on MXene–Cs3Bi2I9 Microplate Schottky Junctions for Weak-Light Detection

“…The unsatisfactory saturation at high illuminance may be related to photocurrent saturation. Further, D * was calculated by D * = ( A · f ) 1 / 2 NEP N E P = ( i n 2 ̅ ) 1 / 2 / R where f is the electrical bandwidth, NEP is the noise equivalent power, and false( i n 2 0em ̅ false) 1 / 2 is the root-mean-square value of the noise current obtained under different frequencies. Figure S11 displays the current noise power spectra at 5 V. The noise current is 2.65 × 10 –13 A Hz –1/2 at 1 Hz and close to 10 –14 A Hz –1/2 at the high frequency.…”

Graphene/MoS2−xOx/graphene photomemristor with tunable non-volatile responsivities for neuromorphic vision processing

“…However, challenges still exist. The VSPDs based on the metal-semiconductormetal structure had a bias-dependent dark current, and the reconfigurable 2D material-based neural network image sensors are volatile and need continuing gate voltage to update weights 9,[18][19][20][21] . To create a non-volatile photodetector with tunable photoresponses requires complex device designs or manufacturing processes, for example, using a floating gate or a ferroelectric gate dielectric.…”