Two-dimensional (2D) layered materials have attracted extensive research interest in the field of high-performance photodetection due to their high carrier mobility, tunable bandgap, stability, and other excellent properties. Herein, we propose a gate-tunable, high-performance, self-driving, and wide detection range phototransistor based on a 2D PtSe₂ on silicon-on-insulator (SOI). Benefiting from the strong built-in electric field of the PtSe₂/Si heterostructure, the phototransistor has a fast response time (rise/fall time) of 36.7/32.6 μs. The PtSe₂/Si phototransistor exhibits excellent photodetection performance over a broad spectral range from ultraviolet to near-infrared, including a responsivity of 1.07 A/W and a specific detectivity of 6.60 × 10⁹ Jones under 808 nm illumination at zero gate voltage. The responsivity and specific detectivity of PtSe₂/Si phototransistor at 5 V gate voltage are increased to 13.85 A/W and 1.90 × 10¹⁰ Jones under 808 nm illumination. Furthermore, the fabricated PtSe₂/Si phototransistor array shows excellent uniformity, reproducibility, and long-term stability in terms of photoresponse performance with negligible variation between pixel cells. The architecture of present PtSe₂/Si on SOI platform paves a new way of a general strategy to realize high-performance photodetectors by combining the advantages of both 2D materials and conventional semiconductors which is compatible with current Si-complementary metal oxide semiconductor (CMOS) process.

Heterostructure is the basic building block for functional optoelectronic devices. Heterostructures consisting of two-dimensional (2D) transition metal dichalcogenides (TMDs) and organic semiconductors are currently attracting great interest for high-performance optoelectronics. However, how to design heterostructure for highly efficient optoelectronic devices remains a big challenge. Here we design high-performance organic semiconductor/WSe₂ heterostructure photodetectors by tailoring the charge transfer effect between 2,2ʹ-((2Z,2ʹZ)-(((4,4,9,9-tetrakis(4-hexylphenyl)-4,9- dihydros-indaceno[1,2-b:5,6-bʹ]dithiophene-2,7-diyl)bis(4-((2-ethylhexyl)oxy)thiophene-5,2-diyl))bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene)) dimalononitrile (IEICO-4F) organic semiconductors with various thicknesses and monolayer WSe₂. With the increase of IEICO-4F layer thickness, the photoluminescence (PL) characteristics of WSe₂ could be completely quenched due to the charge transfer from the lowest unoccupied molecular orbital (LUMO) level of IEICO-4F to the conduction band minimum (CBM) of WSe₂. Benefiting from the exquisite charge transfer behavior, the IEICO-4F/WSe₂ heterojunction photodetector with optimized 6.0-nm thick IEICO-4F shows high performance including the responsivity of 8.32 A/W and specific detectivity of 4.65 × 10¹¹ Jones at incident light of 808 nm. This work demonstrates a simple approach based on PL characteristics to design high-performance IEICO-4F/WSe₂ heterojunction, thus paving the way for the development of excellent optoelectronic devices based on organic/TMD heterostructures.