Enhancement of light extraction in silicon-rich oxide light-emitting diodes by one-dimensional photonic crystal gratings
- Resource Type
- Authors
- J. M. Llorens; Carlos Domínguez; Pablo Aitor Postigo; Joan Juvert; A. González
- Source
- SPIE Proceedings.
- Subject
- Materials science
Silicon
business.industry
chemistry.chemical_element
Substrate (electronics)
law.invention
Wavelength
Optics
chemistry
law
Optoelectronics
Quantum efficiency
business
Light-emitting diode
Visible spectrum
Photonic crystal
Diode
- Language
- ISSN
- 0277-786X
In this work we show the design of one-dimensional nanophotonic structures (photonic crystal gratings) for enhancement of extraction of light with specific wavelengths in light-emitting diodes (LEDs). The LEDs are made of silicon-rich oxide embedding silicon nanolayers with emission in the visible spectrum. The LED structure consists of a poly-silicon top layer 310 nm thick, a silicon-rich oxide layer with nanoparticles and a silicon substrate. The gratings are formed by grooves separated with periods ranging from 200 nm to 600 nm and widths 0.72 times the period engraved on the top layer. We have performed two dimensional finite-difference time-domain simulations to obtain the values for the internal and external quantum efficiency (EQE) in the normal direction in a spectral window from 400 nm to 500 nm. The results show that it is possible to achieve a strong enhancement in the EQE in the short wavelength region (400 nm) while it reaches 5-fold enhancement at longer wavelengths.