"Theoretical analysis of hot electron collection in metal-insulator-metal devices"

Fuming Wang: Nicholas A. Melosh ; SPIE , 08/21/11.

Additional Authors: Nicholas A. Melosh


We propose a new architecture of metal-insulator-metal devices for solar energy harvesting at infrared and visible frequencies based on asymmetrical alignment of insulating barrier relative to the Fermi level of metals and spatial localization of hot electrons excited by photons. Photons absorbed by metals create hot electrons, which can transmit through the thin insulating barrier, producing current. We theoretically investigated the photocurrent response and power generations at different wavelengths. Short circuit current and open circuit voltage can be easily tuned by changing metal thicknesses to adjust the forward and reverse photocurrent. By employing surface plasmons, power generation efficiency is enhanced 9 times in a grating MIM device compared to direct illumination at 650 nm. Finally, we compared the enhancement of power generation efficiency by SPs excited through grating structure and Kretschmann coupling system.