This article reports on ternary Ta-Si-N films with a high (greater than or equal to40 at%) content of Si sputtered from an alloyed TaSi2 target using an unbalanced dc magnetron. The films were deposited under the following conditions: magnetron discharge current Id =1 and 2 A, negative substrate bias Us 2 ranging from U-fl to -500 V, substrate ion current density i(s) =0.5, 0.75, and 1 mA/cm(2), substrate temperature T-s ranging from 100 to 750degreesC, substrate-to-target distance d(s-t) =60mm, partial pressure of nitrogen P-N2 ranging from 0 to 0.7 Pa and two values of a total pressure PT = PAr +(PN2)=0.5 and 0.7 Pa. Main attention is devoted to the investigation of the effect of partial pressure of nitrogen PN2 on mechanical properties of Ta-Si-N films. It was demonstrated that (1) the Ta-Si-N films exhibit an x-ray amorphous structure, (2) all films are electrically conductive but their electrical resistivity increases with increasing Si3N4 content from about 10(-5) to about 10(2) Omega cm, and (3) the hardness H of the Ta-Si-N films is comparable to that of TAN films and achieves relatively high values (Happroximate to30GPa) and so it is considerably higher than that of a bulk Si3N4 material with H-Si3N4 = 17.2 GPa. The interrelationships between mechanical properties-hardness H, Young's modulus E, and elastic recovery W-e-are discussed in detail. Special attention is devoted to the macrostress sigma generated in the Ta-Si-N films during their growth and to the thermal stability of these films. (C) 2004 American Vacuum Society.