Effect of air annealing on opto-electrical properties of amorphous tin oxide films

Abstract

Amorphous tin oxide films, 100-800 nm thick and of resistivity ∼6-8 m cm, were deposited on glass substrates using a filtered vacuum arc with an oxygen background gas pressure of 4.0 mTorr. The films were annealed in air at a temperature of 300˚C for 1, 3, 5, 7, and 10 min. Film morphology, structure, composition, roughness, and light transmission were determined before and after the annealing, on cold samples, with atomic force microscopy, x-ray diffraction diagnostics, x-ray photoelectron spectroscopy, and light transmission meter. The roughness depended weakly on the annealing time, and decreased with the thickness of the film. The film transmission in the visible region was practically independent of the annealing time. Film conductivity increased with the annealing time, reaching a maximum value after 3-7 min, larger by a factor of 2.0-2.9 than that measured before annealing. The oxygen to tin density ratio on the film surface decreased relative to its value before annealing and reached a minimum after annealing for 7 min. After annealing for 10 min, the O/Sn ratio increased relative to the minimum value but was lower than the ratio before annealing. The O/Sn ratio in the bulk decreased monotonically for annealing times longer than 1 min. The film conductivity before and after annealing depended linearly on the film thickness. A model is proposed to elucidate the dependence of the conductivity on the annealing time and on the film thickness.

Electrical, structural and optical properties of SnO2 thin films prepared by spray pyrolysis

“…However at higher temperatures, the surface mobility of constituent elements increases, and the growth of face grains are preferred. The atomic force microscope images undoped SnO 2 are compared with the published results [17,25,[33][34][35][36][37][38]. It is observed that the crystallization processes in undoped SnO 2 with increasing substrate temperature followed similar character, which is shown by XRD analysis, also the degree of surface roughness increases.…”

Influence of annealing on the physical properties of filtered vacuum arc deposited tin oxide thin films

“…In addition, SnO 2 thin films could be deposited with FVAD system on low temperature substrates, such as polymers that could not sustain temperatures above 80°C [16]. The dependence of the structure, composition, and electrical properties of room temperature FVA deposited SnO 2 thin films on the oxygen background pressure (0.42-1.06 Pa), and film thickness (100-800 nm) were reported by Ben-Shalom et al [11], Kaplan et al [12], Alterkop et al [14] and Parkansky et al [15]. All deposited films were amorphous, with the lowest electrical resistivity of 3-5 · 10 À4 X cm, obtained by rapid thermal annealing (RTA) [11,12].…”

“…SnO (TCO) films that contain In or Cd, as they are less expensive and non-toxic. Doped or undoped SnO 2 thin films were prepared by spray pyrolysis [5], reactive electron beam evaporation [6], rf magnetron sputtering [7,8], chemical vapour deposition (CVD) [9], reactive ion assisted deposition [10] and filtered vacuum arc deposition (FVAD) [11][12][13][14][15][16][17].…”

Influence of annealing temperature on the structural and optical properties of As30Te70 thin films

“…One can observe that the optical transmittance decreases as the annealing temperature increases. This may be due to to the structural transformation of the films during annealing [26,27]. It can also be seen that the fundamental absorption edge shifts to higher wavelength with increasing the annealing temperature.…”

“…5, α increases with increasing both the photon energy and annealing temperature. This behavior could be due to the size effect [27]. Depending on the value of α, its spectral distribution can be categorized as high absorption or exponential edge region.…”