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Title: Patterned Regions of Porous Silicon through Trapped Hydrogen Bubbles

Abstract

Hydrogen bubbles trapped around lithographically formed etch pits on silicon single crystal surfaces were used to guide the formation of patterned regions of porous silicon. Optical lithography and wet (electro) chemical etching were utilized in a series of steps to form the etched surface and guide this growth. It was observed that the pits were surrounded by round regions of porous Si suggesting that hydrogen bubbles defined the areas of porous silicon formation. Consistent with earlier results where porosity seemed to form primarily at the bubble edges, a lower overall etch rate was observed near the bubble center. This is consistent with a variable rate of bubble expansion as etching occurred and an ability of the hydrogen to mask or slow the reaction in the bubble center. Contrary to our initial expectations, the surface profile suggested that the region away from the bubbles was also etched, but very uniformly.

Authors:
; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
881682
Report Number(s):
PNNL-SA-46455
Journal ID: ISSN 0003-6951; APPLAB; 8220; KP1303000; TRN: US200613%%69
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 88; Journal Issue: 14
Country of Publication:
United States
Language:
English
Subject:
08 HYDROGEN; BUBBLES; ETCHING; HYDROGEN; MONOCRYSTALS; POROSITY; SILICON; Environmental Molecular Sciences Laboratory

Citation Formats

Ou, Fung S., Saraf, Laxmikant V., and Baer, Donald R. Patterned Regions of Porous Silicon through Trapped Hydrogen Bubbles. United States: N. p., 2006. Web. doi:10.1063/1.2188039.
Ou, Fung S., Saraf, Laxmikant V., & Baer, Donald R. Patterned Regions of Porous Silicon through Trapped Hydrogen Bubbles. United States. doi:10.1063/1.2188039.
Ou, Fung S., Saraf, Laxmikant V., and Baer, Donald R. Mon . "Patterned Regions of Porous Silicon through Trapped Hydrogen Bubbles". United States. doi:10.1063/1.2188039.
@article{osti_881682,
title = {Patterned Regions of Porous Silicon through Trapped Hydrogen Bubbles},
author = {Ou, Fung S. and Saraf, Laxmikant V. and Baer, Donald R.},
abstractNote = {Hydrogen bubbles trapped around lithographically formed etch pits on silicon single crystal surfaces were used to guide the formation of patterned regions of porous silicon. Optical lithography and wet (electro) chemical etching were utilized in a series of steps to form the etched surface and guide this growth. It was observed that the pits were surrounded by round regions of porous Si suggesting that hydrogen bubbles defined the areas of porous silicon formation. Consistent with earlier results where porosity seemed to form primarily at the bubble edges, a lower overall etch rate was observed near the bubble center. This is consistent with a variable rate of bubble expansion as etching occurred and an ability of the hydrogen to mask or slow the reaction in the bubble center. Contrary to our initial expectations, the surface profile suggested that the region away from the bubbles was also etched, but very uniformly.},
doi = {10.1063/1.2188039},
journal = {Applied Physics Letters},
number = 14,
volume = 88,
place = {United States},
year = {Mon Apr 03 00:00:00 EDT 2006},
month = {Mon Apr 03 00:00:00 EDT 2006}
}
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  • No abstract prepared.
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