Pulsed-laser deposition (PLD) of ZnTe was performed at; lambda(pld) = 1064 nm and; lambda(pld) = 532 nm employing nanosecond pulses of a Nd:YAG laser. Thin ZnTe films (thickness approximate to 2 mu m) were deposited at room temperature on fused silica glass substrates. X-ray diffraction revealed the influence of the ablation wavelengths on the deposited film texture. The film formed lambda(pld) = 532 nm is amorphous, whereas the one ablated at lambda(pld) = 1064 nm was amorphous but contained zincblende and wurtzite crystallites as well. The samples exhibited a broad photocurrent response extending into the visible and infrared part of the spectrum to almost 1 eV. The absorption coefficients, which were measured with standard constant photocurrent method (s-CPM), showed that the bandgap of the films is considerably shifted to lower energies of 1.0 eV as compared to the crystalline source material of 2.26 eV. (c) 2005 Elsevier B.V. All rights reserved.
Absorption and photoconductivity properties of ZnTe thin films formed by pulsed-laser deposition on glass
SCHIAVULLI, Luigi;LIGONZO, Teresa;
2005-01-01
Abstract
Pulsed-laser deposition (PLD) of ZnTe was performed at; lambda(pld) = 1064 nm and; lambda(pld) = 532 nm employing nanosecond pulses of a Nd:YAG laser. Thin ZnTe films (thickness approximate to 2 mu m) were deposited at room temperature on fused silica glass substrates. X-ray diffraction revealed the influence of the ablation wavelengths on the deposited film texture. The film formed lambda(pld) = 532 nm is amorphous, whereas the one ablated at lambda(pld) = 1064 nm was amorphous but contained zincblende and wurtzite crystallites as well. The samples exhibited a broad photocurrent response extending into the visible and infrared part of the spectrum to almost 1 eV. The absorption coefficients, which were measured with standard constant photocurrent method (s-CPM), showed that the bandgap of the films is considerably shifted to lower energies of 1.0 eV as compared to the crystalline source material of 2.26 eV. (c) 2005 Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
