Thick and stress-free Sendust films on silicon for recording head cores

LETI's recording heads technology requires the deposition of thick Sendust films on silicon substrates, both materials having very different thermal expansion coefficients. Despite of this unfavorable condition, adherent and stress-controlled films, up to 10 /spl mu/m thick, have first been obtained by facing target sputtering under Ar+ nitrogen atmosphere whose influence is great on films' microstructure. Stress-free state has then been achieved by cumulative rapid thermal annealing when starting from compressive stress-induced films.<
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