Ta(Al)N(C) thin films were deposited by the atomic layer deposition technique using TaCl5 or TaBr5 and NH3 as precursors and Al(CH3)(3) as an additional reducing agent. For comparison TaN thin films were deposited also from TaBr5 and NH3 with and without Zn. The films were analyzed by means of the time-of-flight elastic recoil detection analysis, energy dispersive X-ray spectroscopy. X-ray diffraction, and standard four-point probe method. The deposition temperature was varied between 250 and 400 degreesC. The films contained aluminum, carbon, hydrogen, and chlorine impurities. The chlorine content decreased drastically as the deposition temperature was increased. The film deposited at 400 degreesC contained less than 4 atom % chlorine and also had the lowest resistivity, 1300 mu Omega cm. The barrier properties of the Cu/Ta(Al)N(C)/Si structure were studied by using sheet resistance and X-ray diffraction measurements.