Few-Layer MoS${}_2$/a-Si:H Heterojunction pin-Photodiodes for extended Infrared Detection

Abstract

Few-layer molybdenum disulfide (FL-MoS${}_2$) films have been integrated into amorphous silicon (a-Si:H) pin photodetectors. To achieve this, vertical a-Si:H photodiodes were grown by plasma-enhanced chemical vapor deposition (PE-CVD) on top of large-scale synthesized and transferred homogeneous FL-MoS${}_2$. This novel detector array exhibits long-term stability (more than six month) and outperforms conventional silicon-based pin photodetectors in the infrared range (IR, $\lambda$ = 2120 nm) in terms of sensitivities by up to 50 mAW${}^{-1}$. Photodetectivities of up to 2 x 10${}^{10}$ Jones and external quantum efficiencies of 3 % are achieved. The detectors further feature the additional functionality of bias-dependent responsivity switching between the different spectral ranges. The realization of such scalable detector arrays is an essential step towards pixelated and wavelength-selective sensors operating in the IR spectral range.

References in corpus (4)

• Synthesis of Large-Area MoS2 Atomic Layers with Chemical Vapor Deposition
• Growth of large-area single- and bi-layer graphene by controlled carbon precipitation on polycrystalline Ni surfaces
• Hysteresis in the transfer characteristics of MoS2 transistors
• Flexible hybrid graphene/a-Si:H multispectral photodetectors