Atomic layer deposition of Ta(Al)N(C) thin films using trimethylaluminum as a reducing agent

Ta(Al)N(C) thin films were deposited by the atomic layer deposition techniq ue using TaCl5 or TaBr5 and NH3 as precursors and Al(CH3)(3) as an addition al reducing agent. For comparison TaN thin films were deposited also from T aBr5 and NH3 with and without Zn. The films were analyzed by means of the t ime-of-flight elastic recoil detection analysis, energy dispersive X-ray sp ectroscopy. X-ray diffraction, and standard four-point probe method. The de position temperature was varied between 250 and 400 degreesC. The films con tained aluminum, carbon, hydrogen, and chlorine impurities. The chlorine co ntent decreased drastically as the deposition temperature was increased. Th e film deposited at 400 degreesC contained less than 4 atom % chlorine and also had the lowest resistivity, 1300 mu Omega cm. The barrier properties o f the Cu/Ta(Al)N(C)/Si structure were studied by using sheet resistance and X-ray diffraction measurements. (C) 2001 The Electrochemical Society.