Substrate Temperature Effect on Optical property of ZnO Thin Films

Abstract

Abstract. The transparent conducting ZnO thin films were deposited on glass substrate by ultrasonic spray technique. The optical, electrical and structural properties of the ZnO thin films were studied as a function of the substrate temperatures in the range of 300 to 400 °C. The as deposited film exhibit a hexagonal structure wurtzite and (101) oriented.The value of grain size G = 28 nm is measured of ZnO film at 350 °C. All the films having high transparency in the visible region, the band gap energy decreased from 3.44 to 3.29 eV with increasing the substrate temperatures from 300 to 400 °C, respectively according to the Burstein-Moss effect (blue shift of Eg). The Urbach energy decreased reaching to minimum at 350 °C; indicating to decrease of the defects. The electrical resistivity of the films at 350 °C is 50 Ω.cm. A systematic study on the influence of the substrate temperatures on the optical, electrical and structural properties of ZnO thin films deposited by ultrasonic spray has been reported.

Effect of optical gap energy on the Urbach energy in the undoped ZnO thin films

“…The films were deposited at a substrate temperature of 350 • C. The optical properties of undoped ZnO thin film such a band gap energy and the Urbach energy were obtained from our previous paper [21], and various papers [22][23][24][25][26][27][28][29][30]; they have studied the effect of substrate temperature and precursor molarity on the structural and the optical properties of undoped ZnO thin films, these results are shown in Table 1 In this study, we will show the evolution of the precursor molarity on the Urbach energy and band gap energy, we tried to establish correlations for each model proposed. In our calculations, the Urbach energy can be calculated from precursor molarity and band gap energy of undoped ZnO thin films; the ZnO exhibit a single crystals exhibit n-type semiconductor with a high crystallinity.…”

Extended Wide Band Gap Amorphous ZnO Thin Films Deposited by Spray Pyrolysis

“…Following the JCPD standard files (JPPDS no. 36-1451), the Xpert powder diffractometer of the Wurtzite ZnO structure [10]. This result follows from the fact that the plane (100) perpendicular to the surface of the observed substrate author of 31° is the plane which requires the lowest formation energy.…”

Effect of substrate temperature and oxygen partial pressure on structural and optical properties of Mg doped ZnO thin films

“…Also, the optical band gap energy of deposited films increased with increasing substrate temperature up to 500 1C, which may be due to increase in grain size, band sharpness and BursteinMoss shift. The decrease in band gap above 500 1C can be associated with a decrease in transition tail width [30]. Photoluminescence (PL) spectra (Fig.…”