Cadmium selenide sputtered films

doi:10.1016/0040-6090(77)90340-6

Thin Solid Films

Volume 46, Issue 1, 3 October 1977, Pages 59-67

https://doi.org/10.1016/0040-6090(77)90340-6 Get rights and content

Abstract

Cadmium selenide films were d.c. sputtered in a mixture of hydrogen selenide and argon. The photoconductive properties of these films, which do not require heat treatment, compare favourably with the best film properties reported in the literature for CdS and CdSe. The higher dark resistivity of about 10⁹ ω cm measured through the film compared with about 10⁷ ω cm measured in the plane of the film is attributed to the existence of potential barriers due to stacking faults. Illumination from a tungsten light source of approximately 3 mW cm⁻² decreased the resistivity to 10⁵−10⁶ω cm both through and in the plane of the film, and chopping of the light revealed response times of less than 1 ms. The effects of substrate temperature (15–250 °C), film thickness (0.4−4 μ) and other preparation conditions were studied. The films exhibited current saturation at high fields through the film which was ascribed to hole depletion in a region near the anode.

References (38)

R.M. Moore et al.
Thin Solid Films
(1975)
H.W. Lehmann et al.
Thin Solid Films
(1976)
M. Takeuchi et al.
Thin Solid Films
(1976)
A. Sadhu et al.
Solid State Commun.
(1970)
S.G. Ellis
J. Phys. Chem. Solids
(1968)
H.F. van Heek
Phys. Lett.
(1968)
Y. Yodogawa et al.
Thin Solid Films
(1972)
P. Mark
J. Phys. Chem. Solids
(1964)
J.I.B. Wilson et al.
J. Phys. Chem. Solids
(1973)
L. Däweritz
J. Cryst. Growth
(1974)

V. Snejdar et al.

Thin Solid Films

(1972)

D.S.H. Chan et al.

Thin Solid Films

(1976)

T.N. Bhar et al.

Thin Solid Films

(1974)

S. Durand et al.

Thin Solid Films

(1972)

D.B. Fraser et al.

J. Appl. Phys.

(1972)

W.H. Leighton

J. Appl. Phys.

(1973)

R.H. Bube

Photoconductivity of Solids

T.K. Lakshmanan et al.

K. Tanaka

Jpn. J. Appl. Phys.

(1970)

Cited by (31)

Luminescence and photodetection characteristics of rare earth-doped zinc oxide nanostructures
2022, Ceramic Science and Engineering: Basics to Recent Advancements
In this chapter, luminescence and photodetection of rare earth–doped metal oxide nanostructures, i.e., ZnO nanostructures, has been studied. The chapters are divided into six sections, which include basics of nanoscience and technology and their applications, history of luminescence, and their mechanism in semiconductors at nanoscales, fundamental of photoconductivity and parameters dependence of photoconductivity, negative/anomalous nature of growth, and decay of photocurrent. It further discusses about ZnO as well as their applications at nanoscale for devices. Finally, rare earth elements such as Dy, Gd, Pr, and Ce are discussed in brief followed by discussion about effect of doping of such rare earth elements in ZnO on its luminescence and photodetection properties.
Studies on Ni/(n)CdSe thin film Schottky barrier junction
2022, Materials Today: Proceedings
Citation Excerpt :
These properties are useful for a good theoretical conversion efficiency and has led to the investigations for obtaining efficient solar cells. Extensive studies have been carried out on the different structural, optical and electrical properties of polycrystalline thin films of CdSe prepared by various techniques such as vacuum evaporation [6–9], quasi-closed volume technique [10], electrodeposition [11–14], chemical bath deposition (CBD) [15], spray pyrolysis [16], sputtering [17] etc. Although many investigations on the formation of a Schottky barrier with single crystal bulk CdSe using different metals have been reported [18,19], a little attention has been paid to Schottky barriers formed with polycrystalline CdSe thin films.
Ag doped n-type CdSe thin films of doping concentration up to 5.21 × 10¹⁴ cm⁻³ have been used to fabricate Schottky barrier junction with Ni metal on glass substrates by sequential thermal evaporation. All the junctions of different doping concentrations exhibited rectifying current–voltage (I-V) characteristics with a non-saturating reverse current. From the current density–voltage (J-V) characteristics, the junction parameters such as ideality factor, saturation current density, series resistance, etc., were measured. The junctions were found to possess higher values of ideality factor and series resistance. The Richardson constant evaluated from ln(J₀/T²) vs T⁻¹ plot was found to be 80 after heat treatment and the barrier height was around 0.62 eV. While the barrier height obtained from C-V plot was around 0.65 eV. The structure exhibited poor photovoltaic effect characterized by a fill factor not>0.36. The diode quality as well as photovoltaic performance of the junctions was improved after heat treatment in vacuum at 373 K for 1 hr.
Solvothermal synthesis, deposition and characterization of cadmium selenide (CdSe) thin films by thermal evaporation technique
2011, Journal of Crystal Growth
Citation Excerpt :
It is used to fabricate thin ﬁlm transistors [6], optoelectronic devices, photovoltaic cells [7–9] and light emitting diodes [10]. Mostly CdSe thin films were prepared using physical and chemical methods such as thermal evaporation [11,12], sputtering [13], electron beam evaporation [9,14], chemical bath deposition [15–19], spray pyrolysis [8,20], electrodeposition [21,22], photoelectrochemical [23,24], SILAR [25] and photochemical deposition [26]. Pradip et al. [3], Sarmah et al. [11] reported the deposition of CdSe thin films by the thermal evaporation technique, using the commercially obtained CdSe material from the M/s Sigma Aldrich.
Nanocrystalline compound semiconductor Cadmium Selenide was synthesized by the solvothermal method using Cd(NO₃)₂.4H₂O and Se metal granules. The synthesized nanocrystalline CdSe particles were subjected to vacuum annealing at 450 °C to maintain the hexagonal phase. The as synthesized and annealed powders were analyzed using XRD, SEM, EDX and DTA. The X-ray diffraction pattern of the as synthesized powder shows cubic phase, whereas the 450 °C annealed CdSe powder exhibits hexagonal phase. The annealed nanocrystalline CdSe was pelletized using hydraulic pressure of 5 ton and used to deposit thin films at different substrate temperature like Room Temperature (RT), 150, 250, 350 and 450 °C by thermal evaporation using glass as substrate. The deposited films were subjected to XRD, SEM, EDX, UV–vis, Photoluminescence, Raman Spectroscopy and Hall Effect measurement to study their properties. The thickness of the films was measured with thickness profilometer. The thermally deposited CdSe films exhibit the hexagonal structure with n-type conductivity.
The optoelectronic properties of CdSe: Cu photoconductive detector
2002, Renewable Energy
Photoconductive CdSe doped with (1–5 wt%) of Cu was fabricated using the vacuum evaporation technique for thin-film preparation followed by vacuum annealing at 350°C under an argon environment for doping with copper. The electrical and detection properties as a function of Cu content were studied. It was found that the gain coefficient was increased with an increase in the Cu impurity concentration and better results were obtained for a CdSe:Cu detector of 5 wt% concentration, which showed a gain coefficient of up to 8.87×10³ for white illumination ∼1000 Lux. This value is much greater than the published value for pure CdSe film, possibly due to the sensitizing action of Cu centers. Additional weak but well resolved features were observed in the high-energy region of the curve depicting gain coefficients as a function of wavelength characteristics. These peaks were attributed to the 3D transition of Cu from deep levels in the valence band.
Phase transformation on CdSe thin films under annealing in Ar + Se<inf>2</inf> atmosphere
2000, Journal of Physics and Chemistry of Solids
Citation Excerpt :
The physical properties of CdSe thin films are continuously being studied for their important applications in photovoltaic cells and in the fabrication of electronic devices [1,2]. This material in thin-film form has been grown by employing several techniques: thermal evaporation [3], molecular beam epitaxy (MBE) [4], sputtering [5], chemical bath deposition (CBD) [6], laser ablation [7], among others, both in zincblende (ZB) or wurtzite (W) structures, or in a ZB–W mixture [6,8]. In this work the CBD method was used to grow ZB–CdSe thin films on glass substrates.
Cubic CdSe thin films of approximately 2000 Å thickness have been prepared onto glass substrates by chemical bath deposition. The samples were annealed in an Ar+Se₂ atmosphere at normal pressure for 30 h at different temperatures in the range of 50–500°C, in order to perform the crystalline phase transformation from cubic zincblende (ZB) to the hexagonal wurtzite (W) structure. The characterization of samples included both optical absorption and X-ray diffraction analyses. The optical absorption spectra allowed to calculate the energy band-gap (E_g) values and, hence, the evolution of E_g in the thermally treated samples through the transformation from the cubic crystalline phase to the hexagonal phase. The X-ray diffraction spectra also showed the complete microstructural transformation from as-grown cubic samples up to the entire hexagonal lattice for samples with higher annealing. The critical point of the ZB→W transformation is proposed to occur at 355±25°C.
Direct current conductivity of evaporated cadmium selenide thin films
1999, Physica B: Condensed Matter
Current density–voltage characteristics have been obtained from thin films of CdSe, when sandwiched between ohmic gold and blocking aluminium electrodes. At low voltage, the current in the forward direction varies exponentially with voltage, and the transport mechanism is found to be dominated by recombination at the depletion region. At higher voltage, two distinct regions of ohmic and space-charge limited conduction dominated by a discrete trap level were observed. The thickness dependence in the square-law region has been found to confirm the $d^{−3}$ law.

View all citing articles on Scopus

View full text

Cadmium selenide sputtered films

Abstract

Thin Solid Films

Thin Solid Films

Thin Solid Films

Solid State Commun.

J. Phys. Chem. Solids

Phys. Lett.

Thin Solid Films

J. Phys. Chem. Solids

J. Phys. Chem. Solids

J. Cryst. Growth

Thin Solid Films

Thin Solid Films

Thin Solid Films

Thin Solid Films

J. Appl. Phys.

J. Appl. Phys.

Photoconductivity of Solids

Jpn. J. Appl. Phys.