Abstract
The structural and optical properties of stain-etched porous silicon are investigated using optical microscopy, scanning electron microscopy, ex situ atomic force microscopy (AFM), photoluminescence (PL), and Fourier transform infrared (FTIR) spectroscopy. The stained layers were formed in a 50% HF solution with the addition of an oxidizing agent of KIO3 on n-type silicon substrates with and without light illumination of λ=532nm. Strong yellowish emission is observed only when porous silicon is formed under light illumination and in the limited KIO3 concentrations. Surprisingly enough, no PL emission is observed on stained surfaces formed without light illumination. The surface morphology as characterized by AFM reveals that light illumination can produce microscopic roughnesses on the stained surfaces. No specific chemical species on the stained surfaces can be identified by FTIR spectroscopy. The origin of the yellowish luminescence is hypothesized to be due to the quantum-size effect that enables the nondirect optical transitions via a momentum conservation relaxation.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
