Thickness Dependent on Energy Band Gap and Electrical Conductivity of Undoped Conjugated Polymer Thin Films

2016 ◽  
Vol 846 ◽  
pp. 620-625 ◽  
Author(s):  
Hamizah Nadia Alias@Yusof ◽  
Hasiah Salleh ◽  
Mohd Ikmar Nizam Mohamad Isa
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Electrical Conductivity ◽  
Band Gap ◽  
Energy Band ◽  
Conjugated Polymer ◽  
Polymer Thin Films ◽  
Energy Band Gap ◽  
Lower Energy Band ◽  
Ito Glass

Conjugated polymers have been widely used for electronic purpose applications due to their numerous advantages. This has led many researches to pay their major attention in studying on characteristics of conjugated polymer thin films. The purpose of this study was to investigate the effect of undoped conjugated polymer thin films on their optical and electrical properties. Poly(3-thiophene acetic acid), Polypyrrole and Polythiophene thin film was fabricated on ITO glass substrate by using EIS. Film thickness, energy band gap and electrical conductivity of thin films were characterized by using profilometer, ultraviolet-visible spectrometer and four point probe method respectively. The thickness of each thin film varied between 50.534 nm to 97.03 nm. The result has shown that thicker film has lower energy band gap compared to the thinner one. However the electrical conductivity showed an opposite behavior.

scholarly journals Optoelectronics applications of electrodeposited p- and n-type Al2Se3 thin films

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
A. A. Faremi ◽  
S. S. Oluyamo ◽  
O. Olubosede ◽  
I. O. Olusola ◽  
M. A. Adekoya ◽  
...  
Keyword(s):  
Thin Films ◽  
Electrical Conductivity ◽  
Band Gap ◽  
Energy Band ◽  
Selenium Dioxide ◽  
Photoelectrochemical Cells ◽  
Energy Band Gap ◽  
Cathodic Deposition ◽  
Conductivity Type ◽  
P Type

Abstract In this paper, energy band gaps and electrical conductivity based on aluminum selenide (Al2Se3) thin films are synthesized electrochemically using cathodic deposition technique, with graphite and carbon as cathode and anode, respectively. Synthesis is done at 353 K from an aqueous solution of analytical grade selenium dioxide (SeO2), and aluminum chloride (AlCl2·7H2O). Junctions-based Al2Se3 thin films from a controlled medium of pH 2.0 are deposited on fluorine-doped tin oxide (FTO) substrate using potential voltages varying from 1,000 mV to 1,400 mV and 3 minutes −15 minutes respectively. The films were characterized for optical properties and electrical conductivity using UV-vis and photoelectrochemical cells (PEC) spectroscopy. The PEC reveals a transition in the conduction of the films from p-type to n-type as the potential voltage varies. The energy band gap reduces from 3.2 eV to 2.9 eV with an increase in voltage and 3.3 eV to 2.7 eV with increase in time. These variations indicate successful fabrication of junction-based Al2Se3 thin films with noticeable transition in the conductivity type and energy band gap of the materials. Consequently, the fabricated Al2Se3 can find useful applications in optoelectronic devices.

Absorber Films of Ag2S and AgBiS2 prepared by Chemical Bath Deposition

2002 ◽  
Vol 730 ◽  
Author(s):  
A. Nuñez Rodriguez ◽  
M.T.S. Nair ◽  
P.K. Nair
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Electrical Conductivity ◽  
Silver Nitrate ◽  
Band Gap ◽  
Chemical Bath Deposition ◽  
Optical Band Gap ◽  
Sodium Thiosulfate ◽  
Xrd Pattern ◽  
Glass Substrates

AbstractAg2S thin films of 90 nm to 300 nm in thickness were deposited at 70°C on glass substrates immersed in a bath mixture containing silver nitrate, sodium thiosulfate and dimethylthiourea. When the films are heated in nitrogen at temperatures 200°C to 400°C, crystallinity is improved and XRD pattern similar to that of acanthite is observed. These films possess electrical conductivity of 10-3 (ohm cm)-1, are photoconductive and exhibit an optical band gap of 1.36 eV. When Ag2S thin film is deposited over a thin film of Bi2S3, also obtained by chemical bath deposition from bismuth nitrate, triethanolamine and thioacetamide, and heated at 300°C to 400°C in nitrogen, a ternary compound, AgBiS2 is formed. This material has an electrical conductivity of 5x10-5 (ohm cm)-1, is photoconductive and possesses optical band gap 0.95 eV.

Analysis of Defects and Surface Roughness on the Hydrogenated Amorphous Silicon (a-Si:H) Intrinsic Thin Film for Solar Cells

2019 ◽  
Vol 966 ◽  
pp. 398-403
Author(s):  
Yoyok Cahyono ◽  
Novita Dwi Purnamasari ◽  
Mochamad Zainuri ◽  
Suminar Pratapa ◽  
Darminto
Keyword(s):  
Thin Film ◽  
Surface Roughness ◽  
Solar Cells ◽  
Band Gap ◽  
Indium Tin Oxide ◽  
Energy Band ◽  
Thin Layers ◽  
Oxide Glass ◽  
Energy Band Gap ◽  
Hydrogen Dilution

Effect of defect - through observation of energy absorption Urbach, on deposition rate, energy band gap, and surface roughness of intrinsic thin film are investigated using Radio Frequency Plasma Enhance Chemical Vapor Deposition (RF-PECVD). Films are grown on ITO (Indium Tin Oxide) glass substrate. Analysis of energy band gap is conducted to determine changes in the structure of a thin film of a-Si:H. Energy band gap is important to determine the portion of the spectrum of sunlight that is absorbed solar cells. From the characterization using UV-Vis spectrometer and the Tauc’s plot method, the width of the resulting energy band gap is greater if the hydrogen dilution is increased. It can be shown that the increase of the hydrogen dilution, will increase the energy band gap, and the surface roughness of thin layers. Instead, the improvement of the hydrogen dilution decrease the rate of deposition and Urbach energy. It is estimated that with greater hydrogen dilution, an intrinsic thin film of a-Si:H is more conductive for more reduction in residual of band tail defects or dangling bond defects.

EFFECT OF SYNTHESIS REACTION TIME AND DOPING ON UV/VIS ABSORPTION OF POLYENE COATING

2017 ◽  
Vol 79 (2) ◽  
Author(s):  
Mohd Nurazzi Norizan ◽  
Rahmah Mohamed
Keyword(s):  
Reaction Time ◽  
Band Gap ◽  
Energy Band ◽  
Lower Energy ◽  
Control Sample ◽  
Reaction Times ◽  
Energy Band Gap ◽  
Lower Energy Band ◽  
Dechlorination Reaction ◽  
Absorbance Spectra

Absorbance spectra and energy band gap of synthesizing polyene from dechlorination of polyvinyl chloride (PVC) with varying synthesizing reaction times and doping percentages were examined in this paper. The reaction time of dechlorination was varied from 30 minutes, 1 hour, 2 hours and 4 hours. Polyene obtained from the dechlorination reaction was doped with potassium iodide (KI). Sample for UV/Vis test was prepared in the form of film. Modified EO film as control sample showed that there is only a single absorption peak around 327nm. The C-Cl adsorption band link from source link polymer was observed at 422nm and all polyene film samples and new bands absorption were observed from 422nm to 590nm, and 683nm upon the increase in reaction time. The lower energy band gap was observed at 683.18nm absorption with 1.08eV.    

Energy Band Gap Shift of ZnS-ZnO Thin Films Grown by Pulsed Laser Deposition

2010 ◽  
Vol 404 (1) ◽  
pp. 186-191 ◽  
Author(s):  
J.-K. Chung ◽  
J. W. Kim ◽  
D. Do ◽  
S. S. Kim ◽  
T. K. Song ◽  
...  
Keyword(s):  
Thin Films ◽  
Pulsed Laser Deposition ◽  
Band Gap ◽  
Energy Band ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Zno Thin Films ◽  
Energy Band Gap

scholarly journals Dependence on the Partial Pressure of Oxygen on the Shift in the Energy Band-gap of CdO Thin Films in the Visible Region

2001 ◽  
Vol 24 (1) ◽  
pp. 57-61 ◽  
Author(s):  
M. A. Grado-Caffaro ◽  
M. Grado-Caffaro ◽  
S. L. Sapienza
Keyword(s):  
Thin Films ◽  
Partial Pressure ◽  
Band Gap ◽  
Energy Band ◽  
Visible Region ◽  
Point Of View ◽  
Theoretical Point ◽  
Partial Pressure Of Oxygen ◽  
Energy Band Gap ◽  
Cdo Thin Films

In this paper, the dependence on the partial pressure of oxygen of the shift in the energy band-gap of CdO thin films for the visible region is investigated from the theoretical point of view on an experimental basis. In our analysis, the role played by the dependence of the carrier density upon the above pressure is emphasized.

Sign in / Sign up

Export Citation Format

Share Document