Farzaneh Fadakar MasoulehUniversity of GuilanPhysics GroupRasht, Guilan 41938-33697, IranNarottam DasCurtin UniversityDepartment of Electrical and ComputerEngineeringPerth, Western Australia 6845, AustraliaHamid Reza MashayekhiUniversity of GuilanPhysics GroupRasht, Guilan 41938-33697, IranE-mail: mashhr@guilan.ac.irAbstract. We have demonstrated the possibility of quality light absorptionin plasmonic nanostructured metal-semiconductor-metal (MSM) photode-tectors with different groove shapes and analyzed the device performanceby varying the physical parameters. The simulations revealed the qualitylightabsorptionforvariousnanogratings.TheMSMphotodetectors(MSM-PDs) utilizing nanostructure fabrication enable future high-speed devicesto achieve high-responsivity bandwidth product. Finite difference time-domain method is used to evaluate the quality light absorption by plas-monics one dimensional nanostructures with the illumination of transversemagnetic light, since the surface plasmon polariton excitation is polariza-tion sensitive. In our modeling, various nanograting profiles incorporatedon the conventional MSM-PDs perform in different ways to improve thelight absorption capacity in the subwavelength aperture region of thedevice. Therefore, the grooves’ shape and size are the effective param-eters to enhance the light concentration below the diffraction limit. Thesimulation results demonstrated the light absorption enhancement of∼33.6 times for newly introduced nonlinearly tapered (or trapezoidal)ellipse wall nanogratings with the aid of plasmonic nanogratings effects.