The influence of size effect of conductivity on the microwave absorption properties of thin Al films

Thin Aluminum films with different thickness were deposited on PET substrate by Mid-frequency Magnetron Sputtering (MFMS). The DC conductivity of these thin films was measured using linear four probe method. The microwave absorption properties of the Al-FR4 epoxy layered structure were characterized by vector network analyzer. The results indicated that the size effect on conductivity have a pronounced influence on microwave absorption properties of the thin aluminum film, which were verified by theoretical calculation with transfer matrix method.