Quantum-confinement effects in CdTe-glass composite thin films produced using rf magnetron sputtering

Barrett G Potter, J. H. Simmons

Research output: Contribution to journalArticle

84 Citations (Scopus)

Abstract

Quantum-confinement-induced shifts in the fundamental absorption edge of isolated CdTe crystallites are reported in CdTe-glass composite thin films produced using a sequential rf magnetron sputtering process employing two separate sputtering sources. Films ranging in thickness from 0.5 to 4.5 μm and containing as much as 30 vol % CdTe have been produced, illustrating the versatility of this technique over a more conventional melting approach. Post-deposition heat treatments were used to produce average crystallite sizes in the range 46-158 Å. An improved fit to theory at larger crystal sizes is found if a cylindrical crystal morphology is assumed. The effective mass of the confined specie, which governs the shift of the absorption edge with crystal size, is found to be 0.20m0 (spherical morphology) and 0.12m 0 (cylindrical morphology), both of which are greater than the exciton-reduced mass in bulk CdTe. The data suggests, therefore, that a non-negligible Coulomb interaction may still exist in crystals even as small as 0.31 times the size of the bulk Wannier exciton diameter. Planar waveguiding has also been demonstrated in these samples as a preliminary step to the production of waveguide-based nonlinear device structures.

Original languageEnglish (US)
Pages (from-to)1218-1224
Number of pages7
JournalJournal of Applied Physics
Volume68
Issue number3
DOIs
StatePublished - 1990
Externally publishedYes

Fingerprint

magnetron sputtering
composite materials
glass
thin films
excitons
crystals
crystal morphology
shift
versatility
crystallites
heat treatment
sputtering
melting
waveguides
interactions

ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

Cite this

Quantum-confinement effects in CdTe-glass composite thin films produced using rf magnetron sputtering. / Potter, Barrett G; Simmons, J. H.

In: Journal of Applied Physics, Vol. 68, No. 3, 1990, p. 1218-1224.

Research output: Contribution to journalArticle

@article{db88b546ca194ab29d1b594a338cf479,
title = "Quantum-confinement effects in CdTe-glass composite thin films produced using rf magnetron sputtering",
abstract = "Quantum-confinement-induced shifts in the fundamental absorption edge of isolated CdTe crystallites are reported in CdTe-glass composite thin films produced using a sequential rf magnetron sputtering process employing two separate sputtering sources. Films ranging in thickness from 0.5 to 4.5 μm and containing as much as 30 vol {\%} CdTe have been produced, illustrating the versatility of this technique over a more conventional melting approach. Post-deposition heat treatments were used to produce average crystallite sizes in the range 46-158 {\AA}. An improved fit to theory at larger crystal sizes is found if a cylindrical crystal morphology is assumed. The effective mass of the confined specie, which governs the shift of the absorption edge with crystal size, is found to be 0.20m0 (spherical morphology) and 0.12m 0 (cylindrical morphology), both of which are greater than the exciton-reduced mass in bulk CdTe. The data suggests, therefore, that a non-negligible Coulomb interaction may still exist in crystals even as small as 0.31 times the size of the bulk Wannier exciton diameter. Planar waveguiding has also been demonstrated in these samples as a preliminary step to the production of waveguide-based nonlinear device structures.",
author = "Potter, {Barrett G} and Simmons, {J. H.}",
year = "1990",
doi = "10.1063/1.346720",
language = "English (US)",
volume = "68",
pages = "1218--1224",
journal = "Journal of Applied Physics",
issn = "0021-8979",
publisher = "American Institute of Physics Publising LLC",
number = "3",

}

TY - JOUR

T1 - Quantum-confinement effects in CdTe-glass composite thin films produced using rf magnetron sputtering

AU - Potter, Barrett G

AU - Simmons, J. H.

PY - 1990

Y1 - 1990

N2 - Quantum-confinement-induced shifts in the fundamental absorption edge of isolated CdTe crystallites are reported in CdTe-glass composite thin films produced using a sequential rf magnetron sputtering process employing two separate sputtering sources. Films ranging in thickness from 0.5 to 4.5 μm and containing as much as 30 vol % CdTe have been produced, illustrating the versatility of this technique over a more conventional melting approach. Post-deposition heat treatments were used to produce average crystallite sizes in the range 46-158 Å. An improved fit to theory at larger crystal sizes is found if a cylindrical crystal morphology is assumed. The effective mass of the confined specie, which governs the shift of the absorption edge with crystal size, is found to be 0.20m0 (spherical morphology) and 0.12m 0 (cylindrical morphology), both of which are greater than the exciton-reduced mass in bulk CdTe. The data suggests, therefore, that a non-negligible Coulomb interaction may still exist in crystals even as small as 0.31 times the size of the bulk Wannier exciton diameter. Planar waveguiding has also been demonstrated in these samples as a preliminary step to the production of waveguide-based nonlinear device structures.

AB - Quantum-confinement-induced shifts in the fundamental absorption edge of isolated CdTe crystallites are reported in CdTe-glass composite thin films produced using a sequential rf magnetron sputtering process employing two separate sputtering sources. Films ranging in thickness from 0.5 to 4.5 μm and containing as much as 30 vol % CdTe have been produced, illustrating the versatility of this technique over a more conventional melting approach. Post-deposition heat treatments were used to produce average crystallite sizes in the range 46-158 Å. An improved fit to theory at larger crystal sizes is found if a cylindrical crystal morphology is assumed. The effective mass of the confined specie, which governs the shift of the absorption edge with crystal size, is found to be 0.20m0 (spherical morphology) and 0.12m 0 (cylindrical morphology), both of which are greater than the exciton-reduced mass in bulk CdTe. The data suggests, therefore, that a non-negligible Coulomb interaction may still exist in crystals even as small as 0.31 times the size of the bulk Wannier exciton diameter. Planar waveguiding has also been demonstrated in these samples as a preliminary step to the production of waveguide-based nonlinear device structures.

UR - http://www.scopus.com/inward/record.url?scp=36549097325&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=36549097325&partnerID=8YFLogxK

U2 - 10.1063/1.346720

DO - 10.1063/1.346720

M3 - Article

AN - SCOPUS:36549097325

VL - 68

SP - 1218

EP - 1224

JO - Journal of Applied Physics

JF - Journal of Applied Physics

SN - 0021-8979

IS - 3

ER -