Effect of Co-doping on Microstructural, Crystal Structure and Optical Properties of Ti[sub 1−x]CO[sub x]O[sub 2] Thin films Deposited on Si Substrate by MOCVD Method

Abstract

Tii.xC0x02 thin films have been grown on n-type Si(lOO) substrates by metal organic vapor deposition (MOCVD) using titanium (IV) isopropoxide (TTIP) and tris (2,2,6,6-tetramethyl-3, 5-heptanedionato) cobalt (III) as metal organic precursors. The parameter deposition, such as: bubbler temperature of TTIP Jb(Ti) = 50°C; substrate temperature Ts = 450°C; bubbler pressure Pb(Ti) = 260 Torr; flow rate of Ar gas through TTIP precursor Ar(Ti) =100 seem (standard cubic centimeters per minute) and flow rate of oxygen gas O2 = 60 seem were found as optimal deposition parameters. The thin films deposited were have rutile (002) crystal plane, whereas those deposited at other parameter were mixing of anatase and rutile phases. Co dopant with concentration of up to 5.77% was not changes the structure of Ti02. Increase of Co incorporated in thin films was decreasing of band-gap energy.

CVD Production of Doped Titanium Dioxide Thin Films

“…Cobalt dopant concentrations of up to 5.77% were achieved. It was observed that the band gap was decreased with dopant concentration 88…”