Review—Photodetection Properties of Graphene/Silicon van der Waals Heterojunction

Abstract

Integration of graphene with the bulk semiconductor leads to the formation of van der Waals heterojunction exhibiting distinctive electrical and optical properties which can overcome the intrinsic limitations of isolated two-dimensional and three-dimensional material based devices. This architecture results in the formation of a surface junction; that is the depletion region is just below the one atomic layer and therefore highly accessible photosensitive area. Graphene/Semiconductor junction based optoelectronic devices perform remarkably in the application areas of photodetection, chemical and biological sensing, optical communication and environmental monitoring etc. In particular, Graphene/Silicon van der Waals heterojunction based devices have achieved high photoresponsivity of 5.5 A/W with very high specific detectivity of 5.71 × 1013 jones which is a great milestone in photodetection industry. Therefore, a thorough study of the physics behind the junction and potentiality of the performance of Graphene/Silicon junction based devices will be essential to serve as a basis for the study of more complex nanophotonic devices. Here, we review the state-of-the-art of the research work on the photodetectors based on Graphene/Silicon heterojunction through various modifications, such as introduction of native oxide layer or TiO2, Al2O3 layer and with the integration of different types of nanostructures etc.

A parylene/graphene UV photodetector with ultrahigh responsivity and long term stability

“…The responsivity (R) is a key characteristic of photodetectors, representing the efficiency of the detected optical signal [46]. R was defined as the ratio of photocurrent by the power of optical signal (R = I photocurrent /P) [47].…”

Bias-Modified Schottky Barrier Height-Dependent Graphene/ReSe2 van der Waals Heterostructures for Excellent Photodetector and NO2 Gas Sensing Applications

“…The measured photocurrent at various incident light intensities is significantly higher than what has been observed under dark conditions, revealing the excellent photoresponse of active charge carriers inside the Gr/ReSe 2 heterostructure. Interestingly, a linear relationship between ΔI ph and light power intensities has been observed ( Figure 3 c) which indicates that the larger the light intensity, the higher will be the electron-hole pair generation which leads to the generation of high photocurrent in these devices [ 52 ]. Further, a cyclic measurement was performed which measured photocurrent for five consecutive cycles without any bias voltage at a power intensity of 310 mW/cm 2 , V ds = 1 V and λ = 532 nm ( Figure 3 d).…”

Enhanced photocatalytic performance of the N-rGO/g-C3N4 nanocomposite for efficient solar-driven water remediation

“…In this manner, a Schottky junction is established between rGO and g-C 3 N 4 . 80,81 It is important to note that energy band bending primarily occurs on the side of g-C 3 N 4 , attributed to its semiconductor properties, while rGO exhibits characteristics of a semi-metal. The interaction between these materials gives rise to a space charge zone at the junction, mainly on the g-C 3 N 4 side, which functions as a distinct boundary where electron movement is highly active.…”