METHOD FOR PREPARING BARIUM STRONTIUM TITANATE THIN FILMS BY DIRECT LIQUID INJECTION METAL ORGANIC CHEMICAL VAPOR DEPOSITION USING SPECIFIC RAW MATERIALS UNDER PROPER PROCESS CONDITIONS

摘要

PURPOSE: To provide a method for preparing stoichiometric barium strontium titanate thin films of high quality by direct liquid injection metal organic chemical vapor deposition under the milder conditions using organic complexes of Ba, Sr and Ti that are capable of being vaporized together as raw materials for mixing since they have similar thermal stability, decomposition characteristics and solubility. CONSTITUTION: In a method for preparing barium strontium titanate(BaxSr1-xTiO3) thin films by direct liquid injection metal organic chemical vapor deposition, the method is characterized in that a mixture of Ba(th)2(tmeea), Sr(thd)2(tmeea) and Ti(thd)2(O¬i Pr)2 $ûthd=2,2,6,6-tetramethylheptanedionate, tmeea=tris£2-(2-methoxyethoxy)ethyl|amine, O¬i Pr=isoproxy$ý is used as raw materials of barium, strontium and titanium, wherein the method comprises the steps of: dissolving the raw materials of barium, strontium and titanium into an organic solvent; transferring the solution to an instantaneous vaporizer heated to a temperature of 200 to 250 deg.C so that the solution is vaporized; and injecting the vaporized solution into a deposition container having pressure of 0.5 to 2.0 torr so that the vaporized solution is deposited on a matrix heated to a temperature of 300 to 500 deg.C, wherein the method further comprises a step of heat treating the deposited matrix in a temperature range of 600 to 800 deg.C, and wherein the raw materials of barium, strontium and titanium are mixed in a ratio of 1 ¢¦ 2:1:5 ¢¦ 10.