Giant magneto-impedance ratio in glass covered Co68.5Mn6.5Si10B15 micr
owires. With different glass coat thickness, was measured as a functio
n of dc axial field (up to 10.5 kA/m) and frequency (f=0.5 MHz up to 3
0 MHz). A maximum GMI ratio of 58% was observed at 1.5 MHz. The freque
ncy dependence of the GMI maximum and the position where it occurs is
discussed in terms of the glass coat thickness.