Document Type

Journal Article


Hindawi Publishing Corporation


Faculty of Computing, Health and Science


Electron Science Research Institute (ESRI)




This article was originally published as: Das, N. K., Karar, A. , Tan, C., Alameh, K. , & Lee, Y. (2011). Impact of nanograting phase-shift on light absorption enhancement in plasmonics-based metal-semiconductor-metal photodetectors. Advances in Optical Technologies, 2011(Article ID 504530), 1- 8. Original article available here


The finite difference time-domain (FDTD) method is used to simulate the light absorption enhancement in a plasmonic metal-semiconductor-metal photodetector (MSM-PD) structure employing a metal nanograting with phase shifts. The metal fingers of the MSM-PDs are etched at appropriate depths to maximize light absorption through plasmonic effects into a subwavelength aperture. We also analyse the nano-grating phase shift and groove profiles obtained typically in our experiments using focused ion beam milling and atomic force microscopy and discuss the dependency of light absorption enhancement on the nano-gratings phase shift and groove profiles inscribed into MSM-PDs. Our simulation results show that the nano-grating phase shift blue-shifts the wavelength at which the light absorption enhancement is maximum, and that the combined effects of the nano-grating groove shape and phase shift degrade the light absorption enhancement by up to 50%.

Creative Commons License

Creative Commons Attribution 3.0 License
This work is licensed under a Creative Commons Attribution 3.0 License.


Link to publisher version (DOI)