Electromagnetic shields based on multilayer film structures

Electrodeposited multilayer-film electromagnetic shields are very promising for protecting various devices due to high shielding efficiency and the possibility of depositing on complex-shaped objects. In this communication, we present the results of measurements of the shielding efficiency of such shields. The shields represent alternating layers of materials with high magnetic permeability (Ni-Fe) and high conductivity (Cu). The maximum number of double layers is 45. It is shown that the shielding efficiency in the weak magnetic fields (0.1–0.2 mT) is 8–10; at higher magnetic field strengths (1.5–2.5 mT), it reaches 80–100. It is shown that the shielding factor increases with the number of layers in the shield at the same thickness of a soft magnetic material. A permalloy shield at the same amount of a soft magnetic material has an efficiency lower by a factor of 3–15 depending on the magnetic field strength.