JCE Online Journal of Chemical Education
 | Subscriptions  | Software Orders  | Support  | Contributors  | Advertisers  | 

JCE Print
   Current Issue
 Previous Issues
 Supplements
 Search JCE Index

JCE Digital Library
   DigiDemos
 QBank
 SymMath
 WebWare

JCE Software
   Latest Releases
 Software & Video
 Downloads
 Support

Only@JCE Online
   JCE Online Store
 JCE HS CLIC
 JCE Discussion Forums
   Biographical Snapshots
 ChemEd Resource Shelf
 Featured Molecules
 Hal's Picks
 Project Chemlab
 Reviewed WWW Sites
 "Web-Ed" Articles

About JCE
   Features
 Publications
 Operations
 Outreach
 Contact Us


  Home > JCE Print > Journal of Chemical Education > Issues > 2000  > September  >
In the Laboratory
Understanding the Origin of Luminescence in Porous Silicon: An Undergraduate Solid-State Chemistry Experiment
D. P. Lasher, B. A. DeGraff, and B. H. Augustine
Department of Chemistry, James Madison University, Harrisonburg, VA 22807
Cover
September 2000
Vol. 77 No. 9
p. 1201
Abstract
We report a modular solid-state chemistry experiment based on the chemical and electrochemical etching of crystalline silicon wafers to produce porous silicon (PSi) layers. Under relatively simple etching conditions, porous silicon exhibits efficient room-temperature photoluminescence (PL) at approximately 680 nm. While the luminescence mechanism is still a source of debate, it is generally agreed that the light emission is due to the spatial confinement of electron-hole pairs in nanometer-scale silicon particles that remain after etching. Using this explanation, students are able to apply a three-dimensional particle-in-a-box solution to Schrödinger's equation to explain the energy of the PL as a function of nanoparticle size. We have also compared PSi surfaces with unetched silicon wafers using atomic force microscopy to demonstrate how surface morphology can influence a material's optical properties. This experiment is a tool for introducing chemistry majors to the fabrication and characterization techniques used to study microelectronic materials and provides a solid-state counterpart to molecular absorption measurements typically used to demonstrate the particle-in-a-box principle.
Supplement
Information for instructors and students and a mathcad worksheet generated in Mathcad v. 8.0 are available.
*  Contents JCE2000p1201W.doc (Microsoft Word); JCE2000p1201W.mcd (Mathcad)
*  Download
JCE2000p1201W.pdf

JCE2000p1201W.zip

JCE2000p1201W.sit
More Information
*  Citation
 Lasher, Daniel P.; DeGraff, Benjamin A.; Augustine, Brian H. J. Chem. Educ. 2000 77 1201.
*  Keywords
 Fluorescence Spectrometry; Luminescence; Materials Science; Solid-State Chemistry; Surface Science
*  History
 Created:
Last Updated:		 August 29, 2000
August 31, 2005
<< Previous Article Table of Contents Next Article >>
  Home > JCE Print > Journal of Chemical Education > Issues > 2000  > September  > Page 1201


Subscriptions
 Subscription Info
 Order Forms

JCE HS CLIC

Our Secondary School editors work hard to distill all the JCE materials to produce a fraction of particular interest to high school teachers. We call it CLIC.
 JCE HS CLIC

Contributions Welcome
JCE welcomes your submission
 Contributors' Corner

Advertisers
In recent years we have worked hard to better match our advertisers with our readers. When shopping for chemistry education materials, visit our advertisers' WWW sites first.
 Recent Advertisers

Be An Ambassador
Take JCE along on your outreach missions. Copies of the Journal, guest access to JCE Online, our publications catalog, and more are available for your participants.
 Outreach with JCE

Comments to
jceonline@chem.wisc.edu		 Copyright © Division of Chemical Education, Inc., American Chemical Society.
All rights reserved.