Gallium indium eutectic masking prior to porous silicon formation creates unique spatially-dependent chemistries

We demonstrate that gallium indium (GaIn) eutectic can be used to create interesting crystalline Si/porous silicon (cSi/pSi) platforms that exhibit unique analyte- and spatially-dependent photoluminescence (PL) responses. Here we characterize these cSi/pSi regions by using profilometry, scanning ele...

Full description

Saved in:
Bibliographic Details
Published in:Analytica chimica acta 2018-11, Vol.1032, p.147-153
Main Authors: Collado, Crystal M., Horner, Ian J., Empey, Jennifer M., Nguyen, Lisa N.Q., Bright, Frank V.
Format: Article
Language:English
Subjects:
Correlation analysis
Emission analysis
Eutectics
Fabrication
Fourier transforms
Gallium
Gallium indium eutectic
Gaseous analyte response
Indium
Luminescence
Masking
Organic chemistry
Oxidation
Photoluminescence
Photons
Porosity
Porous silicon
Scanning electron microscopy
Silicon
Spatially-dependent chemistries
Spatially-dependent response
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We demonstrate that gallium indium (GaIn) eutectic can be used to create interesting crystalline Si/porous silicon (cSi/pSi) platforms that exhibit unique analyte- and spatially-dependent photoluminescence (PL) responses. Here we characterize these cSi/pSi regions by using profilometry, scanning electron microscopy (SEM), wide-field PL microscopy, and Fourier transform infrared (FTIR) microscopy. As we move along a vector from the cSi/pSi interface out into “bulk” pSi, the: (i) analyte-dependent, PL-based response initially increases and then decreases; (ii) total PL emission intensity, in the absence of analyte, increases; (iii) pSi thickness increases; and (iv) relative O2Si-H to Si-H band amplitude ratio decreases. Thus, the analyte-dependent PL response magnitude is correlated to the extent of pSi oxidation; which can be easily controlled by using GaIn eutectic as a mask during the pSi fabrication process. [Display omitted] •Unique porous silicon (pSi) microarrays can be created by using GaIn masks.•Array elements show analyte- and spatially-dependent responses.•The relative O2Si-H to Si-H band amplitude ratio is spatially dependent.•Responses arise from competition between analytes and different pSi surface sites.
ISSN:0003-2670
1873-4324
DOI:10.1016/j.aca.2018.05.052