Thin magnetic element and transformer

A thin magnetic element which comprises a coil pattern formed on at least one side of a substrate and a thin magnetic film formed on the coil pattern, wherein:

• said thin magnetic film is represented by the composition formula A.sub.a M.sub.b M'.sub.c L.sub.d, where A represents at least one element selected from the group consisting of Fe, Co and Ni, M represents at least one element selected from the group consisting of lanthanoide type rare earth elements (at least one of La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Lu), Ti, Zr, Hf, V, Nb, Ta and W, M' represents at least one element selected from the group consisting of Al, Si, Cr, Pt, Ru, Rh, Pd and Ir, and L represents at least one element of the group consisting of O and N, and a, b, c and d are compound ratios that satisfy the following relationships:
• 20.ltoreq.a.ltoreq.85, 5.ltoreq.b.ltoreq.30, 0.ltoreq.c.ltoreq.10 and 15.ltoreq.d.ltoreq.55, each in atomic %;
• said thin magnetic film is formed to a thickness of 0.5 .mu.m or greater but 8 .mu.m or smaller;
• that the thickness and width of one turn of a coil conductor constituting the coil pattern are t and a, respectively, an aspect ratio t/a of the coil conductor satisfies the relationship of 0.035.ltoreq.t/a.ltoreq.0.35;
• and
• that the width of one turn of the coil conductor constituting the coil pattern is a and the distance between coil conductor turns that are adjacent each other in the coil pattern is b, the relationship of 0.2<a/(a+b) is satisfied.