Fast, Self‐Driven, Air‐Stable, and Broadband Photodetector Based on Vertically Aligned PtSe₂/GaAs Heterojunction

Abstract

Group-10 layered transitional metal dichalcogenides including PtS2, PtSe2 and PtTe2 are excellent potential candidates for optoelectronic devices due to their unique properties such as high carrier mobility, tunable bandgap, stability and flexibility. Large-area platinum diselenide (PtSe2) with semiconducting characteristics is far scarcely investigated. Here, we report on the development of a high performance photodetector based on vertically aligned PtSe2-GaAs heterojunction which exhibited a broadband sensitivity from deep ultraviolet (DUV) to near infrared (NIR) light, with peak sensitivity from 650 to 810 nm. The Ilight/Idark ratio and responsivity of photodetector were 3×10 4 and 262 mA W −1 measured at 808 nm under zero bias voltage. The response speed of τr/τf were 5.5/6.5 μs, which represented the best result achieved for Group-10 TMDs based optoelectronic device thus far. According to first-principle density functional theory, the broad photoresponse ranging from visible to near infrared region is associated with the semiconducting characteristics of PtSe2 which has interstitial Se atoms within the PtSe2 layers. It was also revealed that the PtSe2/GaAs photodetector did not exhibit performance degradation after 6 weeks in air. The generality of the above good results suggests that the vertically aligned PtSe2 is an ideal material for high-performance optoelectronic systems in the future.

PdSe2 Multilayer on Germanium Nanocones Array with Light Trapping Effect for Sensitive Infrared Photodetector and Image Sensing Application

“…(Please see the detailed calculation process in the Supporting Information.) The responsivity is much better than other group‐10 TMDs based device including PtSe 2 /GaAs and PdSe 2 /Si …”

“…Further device analysis reveals that the PdSe 2 /GeNC arrays device exhibits obvious sensitivity to repeatable 1350, 1550, 1650, and even 2200 nm illumination with good reproducibility. Specifically, the responsivity is estimated to be 530.2 mA W −1 , which is much better than other group‐10 TMDs based device including PtSe 2 /GaAs and PdSe 2 /Si . What is more, the specific detectivity under 1550 nm illumination is 1.45 × 10 11 Jones, respectively.…”

“…In addition to the above 2D materials, PtSe 2 as a representative of the newly discovered group‐10 TMDs has come under spotlight owing to its excellent ambient stability and adjustable bandgap ranging from zero for multilayer to 1.2 eV for monolayer . This thickness‐dependent bandgap greatly facilitates the fabrication of high mobility transistor and high‐performance photodetectors working in infrared light region, which are crucial components for application in various fields, such as missile detection, light vision, target tracking, and military surveillance.…”

Laser Q-switching with PtS2 microflakes saturable absorber

“…The newly discovered group 10 TMDs layered materials such as platinum diselenide (PtSe 2 ) and platinum disulfide (PtS 2 ) have recently attracted great attention, which have been demonstrated to be capable of enabling high performance optoelectronic devices due to their high carrier mobility and broadband light absorption [23][24][25]. The potential applications of layered PtX 2 have already been demonstrated in photocatalyst [23] and field-effect transistors [24,26].…”

Ultrafast Carrier Dynamics and Bandgap Renormalization in Layered PtSe2

“…Recent studies have shown some intriguing properties of PtSe 2 , such as high charge‐carrier mobility, intrinsic patterning, piezoresistivity, and spin‐layer locking . Moreover, PtSe 2 exhibits great potential in electronic and optoelectronic devices, for example, field effect transistors (FETs), spintronics, mid‐infrared photodetectors, gas sensors, valleytronics, and optical modulators . Despite a number of reports addressing the synthesis, electrical properties, and prototype devices, there is still a lack of understanding regarding the carrier dynamics in layered PtSe 2 on an ultrafast time scale.…”