- ( ) LiNbO ( 89/1/1 : - 89/1/14 : ) ( Zn) ( ZnO).. 00-1100 (k) (R) (T) ( 800 o C).. ZnO 800 o C.. : The effect of temperature and heating period on optical properties of ZnO nano layers deposited on LiNbO A. Zendehnam, M. Shirazi and S. Doulatshah Thin Film Laboratory, Physics Department, Faculty of Science, Arak University, Arak, Iran Abstract In this work, the optical properties of ZnO thin films were investigated experimentally. Zinc was sputtered by the magnetron sputtering method on the LiNbO crystal (as substrate), followed by a thermal oxidation at 450 o C of the obtained ZnO films. The variations of the transmittance, reflectance, and extinction coefficient were measured for temperatures (450-800 o C) and different periods of heating (15-10min) which were employed to study their effects on the optical characteristics of the ZnO samples. The optical band gap energy was determined and it showed reduction with temperature and an increase at 800 o C with period of heating. Keywords: ZnO Thin Films, LiNbO, Optical Properties, Magnetron Sputtering. E-mail of corresponding author: A-zendehnam@araku.ac.ir
( ) LiNbO.[ 5] TM (Zn).. ) IR (70nm.[6].[6].[7 8] ( -) (T < 900 o C ) Li O.[7 8].[9] ZnO Zn -900 o C Zn [ 7] 800 ZnO.[10] (RF) DC...[1 ].. 140 o C..[] 110 o C. (IR).[] (Zn,Ti).[4] (TM,TE).[4] (T >1000 o C ). ( 6-8) Li O
( ) LiNbO ( ) ((1) ). ) (.[1] Zn 15 450 o C ) (Zn) (. 60 ( 500-800 o C). 15 Zn ( 10-15) 800 o C. 150 ZnO.[1] (RBS) (A) (T) Camspec model ) 00-1100 (M50.. ZnO..1 (mbar) (A) (V) (mbar) nm/s DC. ZnO. Zn (x-cut) Foctek 99/998 0,5.. 10 0mm² Hind High Vacuum (H.H.V) 1"MSPT. mm 1/5. 99/9 1. 10 5 mbar. (0. 1) 10 1 mbar 50-600 0, -1 A. 600 K 00K.. 400 K [11]. -1 10 0,4 60-5 10 1,95 1.Ultrasonic bath
( ) LiNbO Zn.. Zn 800 o C ZnNb O 6 ( 4 ). X ZnNb O 6 (XRD) (T > 700 o C) [15]. :[16] (α) 1 T0 α = ln( ) (1) t T T T 0 t. ZnO (α) (λ) k λα = 4π. o C) ( 800 : [16] ( ) () ZnO 1-1100. 00 1 ZnO 550 o C.. 1 78 ZnO (,ev) ZnO..[14] 800 o C Zn Zn 800 o C. 1..1
( ) LiNbO 800 o C.( 15 ) ( 6) 800 o C. 6 Zn. αh ν = B( hν ) E g n.[16] () B α hν n. E g. 1/ hν ZnO (αhν) 7 8. E g E g hν (αhν)....4 o C) (800 (k). 5 Zn 800 o C..6 (800 o C).5
( ) LiNbO.[4 7 8 18]. ZnO.[14] temperature( 0 c) Eg (ev). (αhν).7. o 800 C Time (min) LiNbO Eg (ev) ZnO. Zn (/ ev)... (αhν).8 (800 o C) /95 4 ) 450 o C. ([] ZnO /5 ZnO E g. [16 17] (, ev) Zn 700 o C. /19 E g 800 o C 15 ) ( 800 o C Zn 10 (/875ev).
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