Saccharin is a common additive used in nickel iron alloy plating baths for electroplating of NiF e alloy.The reason is that saccharin is beneficial to decrease the internal stress of ferromagnetic thin film

which is unfavorable in many applications of electroplated NiF e alloy.Change of magnetic noise with the long strip iron core based on the unchanged other composition of plating bath is studied while the only concentration of saccharin is changed from 2.5 g/L to 20 g/L.The noise power spectrum density has been measured for the fluxgate sensor based on the long strip iron core made under different saccharin concentration.The results show that a noise spectral density decreased nonlinearly from 9.387nT/H

z

1/2

at 1 Hz for 2.5 g/L saccharin concentration to 1.386nT/Hz

1/2

when saccharin is increased to 20 g/L.This also show that the most common saccharin concentration of 5 g/L in fact is not the best concetration when it comes to minimize the noise of the fluxgate

but larger concentration is required.