A kind of photodiode and preparation method based on tmdcs lateral pin homojunction

Abstract

The invention discloses a photodiode and a preparation method based on a transition metal chalcogenide (TMDCs) lateral PIN homojunction. Through localized surface doping technology, P-type heavily doped regions and N-type heavily doped regions are introduced into intrinsic or lightly doped TMDCs thin films. The doped intrinsic or lightly doped I regions are arranged laterally to form a lateral PIN sandwich structure, in which the P-type heavily doped region and the N-type heavily doped region are respectively covered by metal electrodes. The carrier concentration gradient between the P-type heavily doped region, the intrinsic or lightly doped I region, and the N-type heavily doped region induces carrier diffusion, and the intrinsic or lightly doped I region is completely depleted in the final thermal equilibrium state , the built-in electric field basically falls in the I region. Under the irradiation of incident light, TMDCs in the I region absorb the incident photons to generate electron-hole pairs, and build up an electric field in the I region to separate and drift left and right, and generate voltage or current to output in the circuit to realize photodetection.

Description

technical field [0001] The invention belongs to the technical field of photoelectric detection, and more specifically relates to a photodiode based on a transition metal chalcogenide (TMDCs) lateral PIN homojunction and a preparation method thereof. Background technique [0002] Transition metal dichalcogenides (TMDCs) are a typical two-dimensional layered material. The most common semiconducting TMDCs are MoS composed of VIB transition metals Mo, W, S, and Se. 2 、MoSe 2 、WS 2 and WSe 2 . Studies have shown that photodetectors based on TMDCs have many advantages, such as very high responsivity and specific detectivity. But on the other hand, there are still many areas to be improved in the performance of TMDCs optoelectronic devices at this stage, the most important of which is the slow response speed, resulting in low bandwidth. The response time reported by most studies is on the order of milliseconds (ms) to seconds (s), which severely limits the application of TMDCs...

AI Technical Summary

Problems solved by technology

The response time reported by most studies is on the order of milliseconds (ms) to seconds (s), which severely limits the application of TMDCs-based photodetectors.

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