Improving graphene/4H-SiC/graphene MSM UV photodetector sensitivity using interdigitated electrodes formalism and embedded gold plasmonic nanoparticles
TL;DR: In this article, a novel 4H-SiC metal-semiconductor-metal photodetector design based on Graphene electrode engineering and gold nanoparticles is proposed.
Abstract: In this paper, a novel 4H-SiC metal–semiconductor-metal photodetector design based on Graphene electrode engineering and gold nanoparticles is proposed. The benefits of using an intense light trapping formalism to improve the optical performance of the 4H-SiC PD are investigated by means of an accurate optoelectronic model. The developed model is based on the EMT and avoids the difficulty of considering all nanoparticles. The precision assessment of the built model is carried out by comparison with the experimental data. The findings shed light on the ability of the proposed design to realize the dual task of reducing the unwanted shadowing effect and improving the absorption through Graphene electrode formalism and the Surface Plasmon Resonance effect in the 4H-SiC layer. Furthermore, to optimize the design sensing capability, the proposed model is adopted to formulate fitness functions for the multi-objective genetic algorithm. It is found that for a filling fraction of 0.02 and 7.5 nm radius, the optimized design yields 50 % increase in absorption compared to the standard designs where responsivity of 458 mA/W, PDCR of 3.05 × 106 and response time of 4.7 µs are achieved. These findings confirm the outstanding ability of the proposed design approach to boost up the PD active area for low-cost and high sensing capability, making it valuable for optoelectronic application.
Citations
More filters
01 Feb 2023
TL;DR: In this article , a hybrid approach that combines a light trapping formalism and a metaheuristic optimization approach is suggested to enhance speed and sensing capabilities of a thin film/4H-SiC photodetector (PD).
Abstract: In this paper, a hybrid approach that combines a light trapping formalism and a metaheuristic optimization approach is suggested to enhance speed and sensing capabilities of a thin film/4H–SiC photodetector (PD). To overcome the shadowing problem, interdigitated electrodes made of graphene are employed. Besides, Ag nanoparticles are inserted to enhance photon absorption in the 4H–SiC active area. To avoid the complexity of considering all randomly deposited nanoparticles, the Maxwell-Garnet theory-based dielectric method is employed. The impact of plasmonic engineering factors on the photodetector characteristics is studied. By using embedded Ag nanoparticles and highly transparent graphene electrodes, the proposed device exhibits a maximum responsivity of 269.6 mA/W, a high photocurrent to dark current ratio (PDCR) of 1.7 × 106, a linear-dynamic-range (LDR) of 272 dB, a response time τ = 13.45 μs, and a detectivity of 5.4 × 1013 Jones. In addition, the suggested model is regarded as a fitness function to be used for a Multi Objective Genetic Algorithm (MOGA) optimization method which optimizes the sensing ability of the device and its speed. The optimized design discloses optimum performances in terms of responsivity (564.5 mA/W), PDCR (3.75 × 106), LDR (301 dB), and detectivity (1.25 × 1014 Jones). Also, it balances the compromise between sensing performance and response time (τ = 4.7 μs). Our results show that using an efficient light trapping formalism and a metaheuristic optimization technique, it is possible to notably improve the photodetector sensitivity.
References
More filters
TL;DR: In this paper, an experimental investigation of magneto-transport in a high-mobility single layer of Graphene is presented, where an unusual half-integer quantum Hall effect for both electron and hole carriers in graphene is observed.
Abstract: When electrons are confined in two-dimensional materials, quantum-mechanically enhanced transport phenomena such as the quantum Hall effect can be observed. Graphene, consisting of an isolated single atomic layer of graphite, is an ideal realization of such a two-dimensional system. However, its behaviour is expected to differ markedly from the well-studied case of quantum wells in conventional semiconductor interfaces. This difference arises from the unique electronic properties of graphene, which exhibits electron–hole degeneracy and vanishing carrier mass near the point of charge neutrality1,2. Indeed, a distinctive half-integer quantum Hall effect has been predicted3,4,5 theoretically, as has the existence of a non-zero Berry's phase (a geometric quantum phase) of the electron wavefunction—a consequence of the exceptional topology of the graphene band structure6,7. Recent advances in micromechanical extraction and fabrication techniques for graphite structures8,9,10,11,12 now permit such exotic two-dimensional electron systems to be probed experimentally. Here we report an experimental investigation of magneto-transport in a high-mobility single layer of graphene. Adjusting the chemical potential with the use of the electric field effect, we observe an unusual half-integer quantum Hall effect for both electron and hole carriers in graphene. The relevance of Berry's phase to these experiments is confirmed by magneto-oscillations. In addition to their purely scientific interest, these unusual quantum transport phenomena may lead to new applications in carbon-based electronic and magneto-electronic devices.
11,122 citations
TL;DR: It is shown that the opacity of suspended graphene is defined solely by the fine structure constant, a = e2/hc � 1/137 (where c is the speed of light), the parameter that describes coupling between light and relativistic electrons and that is traditionally associated with quantum electrodynamics rather than materials science.
Abstract: There are few phenomena in condensed matter physics that are defined only by the fundamental constants and do not depend on material parameters. Examples are the resistivity quantum, h/e2 (h is Planck's constant and e the electron charge), that appears in a variety of transport experiments and the magnetic flux quantum, h/e, playing an important role in the physics of superconductivity. By and large, sophisticated facilities and special measurement conditions are required to observe any of these phenomena. We show that the opacity of suspended graphene is defined solely by the fine structure constant, a = e2/hc feminine 1/137 (where c is the speed of light), the parameter that describes coupling between light and relativistic electrons and that is traditionally associated with quantum electrodynamics rather than materials science. Despite being only one atom thick, graphene is found to absorb a significant (pa = 2.3%) fraction of incident white light, a consequence of graphene's unique electronic structure.
7,952 citations
TL;DR: The reflectance and the phase change on reflection from semiconductor-metal interfaces (including the case of metallic multilayers) can be accurately described by use of the proposed models for the optical functions of metallic films and the matrix method for multilayer calculations.
Abstract: We present models for the optical functions of 11 metals used as mirrors and contacts in optoelectronic and optical devices: noble metals (Ag, Au, Cu), aluminum, beryllium, and transition metals (Cr, Ni, Pd, Pt, Ti, W). We used two simple phenomenological models, the Lorentz-Drude (LD) and the Brendel-Bormann (BB), to interpret both the free-electron and the interband parts of the dielectric response of metals in a wide spectral range from 0.1 to 6 eV. Our results show that the BB model was needed to describe appropriately the interband absorption in noble metals, while for Al, Be, and the transition metals both models exhibit good agreement with the experimental data. A comparison with measurements on surface normal structures confirmed that the reflectance and the phase change on reflection from semiconductor-metal interfaces (including the case of metallic multilayers) can be accurately described by use of the proposed models for the optical functions of metallic films and the matrix method for multilayer calculations.
3,629 citations
TL;DR: It is demonstrated that ordered arrays of silicon nanowires increase the path length of incident solar radiation by up to a factor of 73, which is above the randomized scattering (Lambertian) limit and is superior to other light-trapping methods.
Abstract: Thin-film structures can reduce the cost of solar power by using inexpensive substrates and a lower quantity and quality of semiconductor material. However, the resulting short optical path length and minority carrier diffusion length necessitates either a high absorption coefficient or excellent light trapping. Semiconducting nanowire arrays have already been shown to have low reflective losses compared to planar semiconductors, but their light-trapping properties have not been measured. Using optical transmission and photocurrent measurements on thin silicon films, we demonstrate that ordered arrays of silicon nanowires increase the path length of incident solar radiation by up to a factor of 73. This extraordinary light-trapping path length enhancement factor is above the randomized scattering (Lambertian) limit (2n2 ∼ 25 without a back reflector) and is superior to other light-trapping methods. By changing the silicon film thickness and nanowire length, we show that there is a competition between impr...
2,115 citations
TL;DR: A comparative study of various materials including metals, metal alloys and heavily doped semiconductors is presented in this article, where the performance of each material is evaluated based on quality factors defined for each class of plasmonic devices.
Abstract: Plasmonics is a research area merging the fields of optics and nanoelectronics by confining light with relatively large free-space wavelength to the nanometer scale - thereby enabling a family of novel devices. Current plasmonic devices at telecommunication and optical frequencies face significant challenges due to losses encountered in the constituent plasmonic materials. These large losses seriously limit the practicality of these metals for many novel applications. This paper provides an overview of alternative plasmonic materials along with motivation for each material choice and important aspects of fabrication. A comparative study of various materials including metals, metal alloys and heavily doped semiconductors is presented. The performance of each material is evaluated based on quality factors defined for each class of plasmonic devices. Most importantly, this paper outlines an approach for realizing optimal plasmonic material properties for specific frequencies and applications, thereby providing a reference for those searching for better plasmonic materials.
1,615 citations