The peel strength and peel angle of Cr/BPDA-PDA interfaces were measured using the T-peel rest for Cu/Cr/BPDA-PDA structures, When the Cu/Cr metal film war thin, plastic bending of the metal film occurred during the T-peel test, With a thicker metal film, however. plastic bending of BPDA-PDA polyimide was observed. The critical thickness of the metal film for the transition from metal film bending to polyimide bending became thinner M with decreasing yield strength of the metal film, Regardless of the metal film bending or polyimide bending during the T-peel rest, the peel strength increased with higher peel angle and the failure mode or the Cr/BPDA-PDA interfaces was cohesive failure within BPDA-PDA.