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We have developed a new structure that has a GMR sandwich and one or two Au layers at the outer boundaries (Au/NiFe/Cu/CoFe/Au). This structure is designed to employ a specular reflection of conduction electrons from the Au layers. The potential advantages of this structure compared to multilayer films are low saturation field, high sheet resistance and the ability to use scissoring fields from a current for patterned narrow line structures, while maintaining a high GMR. All layers were deposited using rf diode sputtering. Coercivity difference between the two magnetic layers is used to realize the antiparallel alignments of the magnetizations of NiFe and CoFe layers. Comparing with similar structures without Au layers, the new structure has a GMR increase of 35% after discounting the shunting effect of the Au underlayers. Single layer Au films as thin as 40 [Angstrom] have been made with a large specularity parameter when deposited on [Bi.sub.2][O.sub.3] and after annealing.

Memory elements 0.2 microns wide made from multilayer GMR material have been studied experimentally and analytically. When etched into narrow elements, the 12 to 15% material exhibits a memory mode with large outputs of [+ or -] 8%. Analysis shows that the mode is suitable for multi-megabit die with high performance if yield can be achieved.

Multiple, high sensitivity, GMR read head sensors were made and experimentally evaluated. The sensors were 1 micron wide and 10 microns long with flux gathering tips that expanded to 1.5, 2.0, and 3.0 microns. The sensors were found to have saturated outputs of 1.6 mV per micron of length for sense currents of 2.5 mA. The sensors had a very high sensitivity of 0.7% change in resistance per Oe of signal field because of the low effective anisotropy of the sensor material. Test were performed in a uniform field at a frequency of 5 KHz on sensors without shields. Fields of + - 4 Oe were sufficient to provide excitation over the full linear range. The experimental GMR material had a M-R coefficient of 6 % and an anisotropy field of 5 Oe along the long axis of the sensor. The non uniform ternary magnetic layers were 55 [A.sup.o] thick and the copper middle layers were 25 to 30 [A.sup.o] thick.