Electrodeposition of PbS, PbSe and PbTe thin films

Dissertation

Research output: ThesisDissertationCollection of Articles

Abstract

Lead chalcogenides (PbS, PbSe, PbTe) are narrow band gap semiconductors which are largely used in infrared applications. In the present study lead chalcogenide thin films were deposited electrochemically from aqueous solutions. Two different electrodeposition methods were used; PbSe and PbTe thin films were prepared at constant potential while PbS was deposited by cycling the potential. Chemical and physical properties of the films were examined by various techniques, and their electrical properties were studied as well. PbSe and PbS thin films were found to be stoichiometric whereas PbTe thin films contained an excess of Te. The films contained water as an impurity. All the films had polycrystalline, randomly oriented cubic structure. After annealing the films showed p-type conductivity. The annealing at 100 °C did not affect much the resistivities of PbS and PbTe which remained between 0.5-10 W cm but the resistivity of PbSe films increased to 1-60 kW cm. All films showed IR activity. Electrodeposition mechanisms of PbSe, PbTe and PbS thin films and electrochemistry of the related precursors were studied by means of the electrochemical quartz crystal microbalance (EQCM) combined with cyclic voltammetry. Both film growth and EQCM studies showed that the electrodeposition of PbSe and PbTe occurs by the induced codeposition mechanism, where Se (or Te) is deposited first and induces the reduction of lead ions to form PbSe (or PbTe) so that this occurs at more positive potential than where lead alone would be deposited. Electrodeposition of PbS, on the other hand, turned out to be complicated including several simultaneous processes.
Original languageEnglish
QualificationDoctor Degree
Awarding Institution
  • University of Helsinki
Supervisors/Advisors
  • Leskelä, Markku, Supervisor, External person
  • Ritala, Mikko, Supervisor, External person
Award date15 Dec 2000
Place of PublicationEspoo
Publisher
Print ISBNs951-38-5587-2
Electronic ISBNs951-38-5588-0
Publication statusPublished - 2000
MoE publication typeG5 Doctoral dissertation (article)

Fingerprint

electrodeposition
thin films
quartz crystals
microbalances
electrical resistivity
annealing
chalcogenides
electrochemistry
chemical properties
narrowband
physical properties
electrical properties
aqueous solutions
impurities
conductivity
cycles
water
ions

Keywords

  • lead chalcogenides
  • chalcogenide compounds
  • electrochemical quartz crystal microbalance = EQCM
  • cyclic voltammetry
  • film growth
  • metal film deposition
  • electroanalytical techniques

Cite this

Saloniemi, H. (2000). Electrodeposition of PbS, PbSe and PbTe thin films: Dissertation. Espoo: VTT Technical Research Centre of Finland.
Saloniemi, Heini. / Electrodeposition of PbS, PbSe and PbTe thin films : Dissertation. Espoo : VTT Technical Research Centre of Finland, 2000. 84 p.
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abstract = "Lead chalcogenides (PbS, PbSe, PbTe) are narrow band gap semiconductors which are largely used in infrared applications. In the present study lead chalcogenide thin films were deposited electrochemically from aqueous solutions. Two different electrodeposition methods were used; PbSe and PbTe thin films were prepared at constant potential while PbS was deposited by cycling the potential. Chemical and physical properties of the films were examined by various techniques, and their electrical properties were studied as well. PbSe and PbS thin films were found to be stoichiometric whereas PbTe thin films contained an excess of Te. The films contained water as an impurity. All the films had polycrystalline, randomly oriented cubic structure. After annealing the films showed p-type conductivity. The annealing at 100 °C did not affect much the resistivities of PbS and PbTe which remained between 0.5-10 W cm but the resistivity of PbSe films increased to 1-60 kW cm. All films showed IR activity. Electrodeposition mechanisms of PbSe, PbTe and PbS thin films and electrochemistry of the related precursors were studied by means of the electrochemical quartz crystal microbalance (EQCM) combined with cyclic voltammetry. Both film growth and EQCM studies showed that the electrodeposition of PbSe and PbTe occurs by the induced codeposition mechanism, where Se (or Te) is deposited first and induces the reduction of lead ions to form PbSe (or PbTe) so that this occurs at more positive potential than where lead alone would be deposited. Electrodeposition of PbS, on the other hand, turned out to be complicated including several simultaneous processes.",
keywords = "lead chalcogenides, chalcogenide compounds, electrochemical quartz crystal microbalance = EQCM, cyclic voltammetry, film growth, metal film deposition, electroanalytical techniques",
author = "Heini Saloniemi",
year = "2000",
language = "English",
isbn = "951-38-5587-2",
series = "VTT Publications",
publisher = "VTT Technical Research Centre of Finland",
number = "423",
address = "Finland",
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}

Saloniemi, H 2000, 'Electrodeposition of PbS, PbSe and PbTe thin films: Dissertation', Doctor Degree, University of Helsinki, Espoo.

Electrodeposition of PbS, PbSe and PbTe thin films : Dissertation. / Saloniemi, Heini.

Espoo : VTT Technical Research Centre of Finland, 2000. 84 p.

Research output: ThesisDissertationCollection of Articles

TY - THES

T1 - Electrodeposition of PbS, PbSe and PbTe thin films

T2 - Dissertation

AU - Saloniemi, Heini

PY - 2000

Y1 - 2000

N2 - Lead chalcogenides (PbS, PbSe, PbTe) are narrow band gap semiconductors which are largely used in infrared applications. In the present study lead chalcogenide thin films were deposited electrochemically from aqueous solutions. Two different electrodeposition methods were used; PbSe and PbTe thin films were prepared at constant potential while PbS was deposited by cycling the potential. Chemical and physical properties of the films were examined by various techniques, and their electrical properties were studied as well. PbSe and PbS thin films were found to be stoichiometric whereas PbTe thin films contained an excess of Te. The films contained water as an impurity. All the films had polycrystalline, randomly oriented cubic structure. After annealing the films showed p-type conductivity. The annealing at 100 °C did not affect much the resistivities of PbS and PbTe which remained between 0.5-10 W cm but the resistivity of PbSe films increased to 1-60 kW cm. All films showed IR activity. Electrodeposition mechanisms of PbSe, PbTe and PbS thin films and electrochemistry of the related precursors were studied by means of the electrochemical quartz crystal microbalance (EQCM) combined with cyclic voltammetry. Both film growth and EQCM studies showed that the electrodeposition of PbSe and PbTe occurs by the induced codeposition mechanism, where Se (or Te) is deposited first and induces the reduction of lead ions to form PbSe (or PbTe) so that this occurs at more positive potential than where lead alone would be deposited. Electrodeposition of PbS, on the other hand, turned out to be complicated including several simultaneous processes.

AB - Lead chalcogenides (PbS, PbSe, PbTe) are narrow band gap semiconductors which are largely used in infrared applications. In the present study lead chalcogenide thin films were deposited electrochemically from aqueous solutions. Two different electrodeposition methods were used; PbSe and PbTe thin films were prepared at constant potential while PbS was deposited by cycling the potential. Chemical and physical properties of the films were examined by various techniques, and their electrical properties were studied as well. PbSe and PbS thin films were found to be stoichiometric whereas PbTe thin films contained an excess of Te. The films contained water as an impurity. All the films had polycrystalline, randomly oriented cubic structure. After annealing the films showed p-type conductivity. The annealing at 100 °C did not affect much the resistivities of PbS and PbTe which remained between 0.5-10 W cm but the resistivity of PbSe films increased to 1-60 kW cm. All films showed IR activity. Electrodeposition mechanisms of PbSe, PbTe and PbS thin films and electrochemistry of the related precursors were studied by means of the electrochemical quartz crystal microbalance (EQCM) combined with cyclic voltammetry. Both film growth and EQCM studies showed that the electrodeposition of PbSe and PbTe occurs by the induced codeposition mechanism, where Se (or Te) is deposited first and induces the reduction of lead ions to form PbSe (or PbTe) so that this occurs at more positive potential than where lead alone would be deposited. Electrodeposition of PbS, on the other hand, turned out to be complicated including several simultaneous processes.

KW - lead chalcogenides

KW - chalcogenide compounds

KW - electrochemical quartz crystal microbalance = EQCM

KW - cyclic voltammetry

KW - film growth

KW - metal film deposition

KW - electroanalytical techniques

M3 - Dissertation

SN - 951-38-5587-2

T3 - VTT Publications

PB - VTT Technical Research Centre of Finland

CY - Espoo

ER -

Saloniemi H. Electrodeposition of PbS, PbSe and PbTe thin films: Dissertation. Espoo: VTT Technical Research Centre of Finland, 2000. 84 p.