Metal-semiconductor-metal (MSM) photodetectors with plasmonic nanogratings*

Abstract

We discuss the light absorption enhancement factor dependence on the design of nanogratings inscribed into metal-semiconductor-metal photodetector (MSM-PD) structures. These devices are optimized geometrically, leading to light absorption improvement through plasmon-assisted effects. Finite-difference time-domain (FDTD) simulation results show ~50 times light absorption enhancement for 850 nm light due to improved optical signal propagation through the nanogratings. Also, we show that the light absorption enhancement is strongly dependent on the nanograting shapes in MSM-PDs.

Nano-grating Assisted Light Absorption Enhancement for MSM-PDs Performance Improvement: An Updated Review

“…Figure 3b shows images of photo-resist developed plasmonic metal nano-grating structures etched inside the top part of the Au layer using the focused ion beam (FIB) milling process, while Figure 3c shows the images of practically developed photo-resist nano-grating structures together with the development process sequences. It is suggested that employing the FIB milling method to generate nano-gratings structure (i.e., particularly on top of metallic substrates) is preferable to traditional photolithography processes for cutting sharp-edge profiles [72].…”

“…milling method to generate nano-gratings structure (i.e., particularly on top of metallic substrates) is preferable to traditional photolithography processes for cutting sharp-edge profiles [72]. Light absorption is improved by catching and transferring more optical power to the device's absorbing active areas.…”

Design of an agile optical switcher based on a 1D silver plasmonic nanograting filled with a nonlinear Kerr material

“…Out of various metals, silver (Ag) and gold (Au) and commonly used metals in the gratings due to their high corrosion resistance and very good reflection in the visible and infrared spectrums [5,6]. In particular, the shape and wavelength of the plasmon resonances can be tuned by varying the amplitude, shape, and size of the grating topology, which makes the metallic gratings a powerful platform for tunable sensors, absorbers, etc [7][8][9][10][11][12][13][14][15]. For example, it has been shown that a metallic grating-based structure presents higher sensitivity than that of a dielectric grating [7].…”

“…For example, it has been shown that a metallic grating-based structure presents higher sensitivity than that of a dielectric grating [7]. Das et al [8] demonstrated that the light absorption enhancement factor of the metal-semiconductor-metal photodetector (MSM-PD) depends not only on the gap width between the nanogratings, but also on the shape of the grating. Karar et al [9] fabricated a plasmonic based MSM-PD employing nanogratings and demonstrated substantial enhancement in device responsivity.…”