Application of High Rate Magnetron Sputtering to the Fabrication of A-15 Compounds

摘要

High quality Nb sub 3 Sn films have been fabricated using a recently developed magnetron sputtering process capable of deposition rates approaching 1 mu m/min. at sputtering voltages less than 500 V and power levels of about 5 KW. Low sputtering voltages allow more complete thermalization at lower pressures of the material condensing on the substrate which can improve long range order. Transition temperatures of up to 18.3 exp 0 K, J/sub c/(O)'s of 15 x 10 exp 6 A/cm exp 2 and Hc sub 2 as high as 240 kOe have been achieved in 1-3 mu m films deposited from a Nb sub 3 Sn reacted powder target with substrate temperatures between 600 and 800 exp 0 C. The films exhibit smooth surfaces and, generally, a (200) preferred orientation. The growth of the film is columnar in nature. The sputtering parameters, substrate material and temperature will be related to film structure T/sub c/ and J/sub c/(H,T) and the Nb/Sn ratio as determined by Rutherford backscattering. (ERA citation 02:026925)