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dc.contributor.advisorWood, Richard F.
dc.contributor.advisorLowndes, Douglas H.
dc.contributor.advisorFenner, David B.
dc.contributor.authorEsman, Ronald D.
dc.descriptioniii, 52 p.en_US
dc.description.abstractThe theoretical electrical effects of grain boundaries in polycrystalline' silicon are discussed. Zook's model for the electrical effects of a grain boundary is reviewed. Then experimental techniques, with which to test and apply the model, are discussed. A microprocessor-controlled XY table was used to generate scans of a light spot across grain boundaries in polycrystalline-silicon solar cells. An interface was designed to duplicate the induced-current response on an XY-recorder display. Zook's model was then checked for validity by the following measurements. Grain-boundary scans were performed at two laser wavelengths (.6328µm and 1.152µm) and with a filtered, collimnated tungsten source. The grain-boundary surface recombination velocity, s. was determined to be (2.3 ± 0.2) x 10 3 cm/sec. The intragranular minority-carrier diffusion length, L. was also determined: L = (200 ± 25)µm for Monsanto 1mm grain-size material. After passivation, s was reduced to (3.5 ± 0.1) x 10 2 cm/sec. and L was reduced to (140 ± 15µm. The L measurement was observed to be independent of the wavelength of the incident light. which suggest that Zook's model of the intragranular material is valid. However. the observed dependence of s on the wavelength of the incident light does not support Zook's grain-boundary model, but may be explained within the model.en_US
dc.description.sponsorshipSolid State Division. Oak Ridge National Laboratory. Oak Ridge, Tennessee.
dc.relation.ispartofKalamazoo College Physics Senior Individualized Projects Collection
dc.relation.ispartofseriesSenior Individualized Projects. Physics.;
dc.rightsU.S. copyright laws protect this material. Commercial use or distribution of this material is not permitted without prior written permission of the copyright holder. All rights reserved.
dc.titleScanning Light-Spot Measurements on Grain Boundaries in Polycrystalline-Silicon Solar Cellsen_US
KCollege.Access.ContactIf you are not a current Kalamazoo College student, faculty, or staff member, email to request access to this thesis.

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  • Physics Senior Integrated Projects [335]
    This collection includes Senior Integrated Projects (SIP's) completed in the Physics Department. Abstracts are generally available to the public, but PDF files are available only to current Kalamazoo College students, faculty, and staff.

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