Graphene–Silicon Device for Visible and Infrared Photodetection

Abstract

The fabrication of a graphene-silicon (Gr-Si) junction involves the formation of a parallel metalinsulator-semiconductor (MIS) structure, which is often disregarded but plays an important role in the optoelectronic properties of the device. In this work, the transfer of graphene onto a patterned ntype Si substrate, covered by Si3N4, produces a Gr-Si device in which the parallel MIS consists of a Gr-Si3N4-Si structure surrounding the Gr-Si junction. The Gr-Si device exhibits rectifying behavior with a rectification ratio up to 10 4 . The investigation of its temperature behavior is necessary to accurately estimate the Schottky barrier height at zero bias, 𝜑 𝑏0 = 0.24 𝑒𝑉, the effective Richardson's constant, 𝐴 * = 7 × 10 −10 𝐴𝐾 −2 𝑐𝑚 −2 , and the diode ideality factor. n=2.66 of the Gr-Si junction. The device is operated as a photodetector in both photocurrent and photovoltage mode in the visible and infrared (IR) spectral regions. A responsivity up to 350 mA/W and external quantum efficiency (EQE) up to 75% is achieved in the 500-1200 nm wavelength range. A decrease of responsivity to 0.4 mA/W and EQE to 0.03% is observed above 1200 nm, that is in the IR region beyond the silicon optical bandgap, in which photoexcitation is driven by graphene. Finally, a model based on two back-to-back diodes, one for the Gr-Si junction the other for the Gr-Si3N4-Si MIS structure, is proposed to explain the electrical behavior of the Gr-Si device.

Controllable Coupling Effects Enhance the Performance of Ionic-Polymer-Gated Graphene Photodetectors

“…It can be inferred that the application of the positive V tg changes the orientation of the graphene–silicon Schottky junction, which is self-consistent with the previous appearance of the negative photoconductivity effect in Figure . The Schottky barrier height (SBH = 0.47 eV) can be extracted from the slope of the forward bias linear region when V tg = 0 V according to the equation. , where A is the effective junction area, A * is the effective Richardson constant, and η is the diode ideality factor. Based on this formula, both η and Φ B can be estimated via linear fitting of the ln J – V curve in the forward bias linear region.…”

Fabricating Graphene Oxide/h-BN Metal Insulator Semiconductor Diodes by Nanosecond Laser Irradiation

“…Hence, the relevant characteristics are tunneling-driven. For laser-annealed rGO/Si diodes, the literature suggests a rGO/Si SBH from 0.11 to 0.86 eV [ 44 , 45 ]. Hence, a departure from Schottky diodes to MIS diodes increases the overall barrier height, providing an opportunity for significant improvement in diode rectification characteristics.…”

Construction of Bi2O2Se/Bi2Se3 Van Der Waals Heterostructures for Self-Powered and Broadband Photodetectors

“…1,2 Abundant works have confirmed that 2D semiconductor materials, such as graphene, 3,4 black phosphorus (BP), 5,6 transition metal dichalcogenides (TMDs), 7,8 etc., are promising in the development of high-performance and broadband photodetectors. Because of its gapless nature, 9,10 graphene has a wide spectral response range. However, graphene requires extra treatments to enhance its photon absorption due to the single atomic layer structure, resulting in a relatively low absorption coefficient.…”

“…In recent years, high-performance and wide-spectrum photodetectors have attracted increasing attention due to their extensive applications and potential in autonomous driving, environmental monitoring, security systems, imaging, and other frontier fields. , Abundant works have confirmed that 2D semiconductor materials, such as graphene, , black phosphorus (BP), , transition metal dichalcogenides (TMDs), , etc., are promising in the development of high-performance and broadband photodetectors. Because of its gapless nature, , graphene has a wide spectral response range. However, graphene requires extra treatments to enhance its photon absorption due to the single atomic layer structure, resulting in a relatively low absorption coefficient.…”