of the flipped over second semiconductor structure cutting along a a u2032 shown in fig1 a and the cross section of the first semiconductor structure cutting along a a u2032 shown in fig9 a on the bottom after the second step similarly fig1 b shows the combination of the cross section of the flipped over second semiconductor structure cutting along b b u2032 shown in fig1 a and the cross section of the first semiconductor structure cutting along b b u2032 shown in fig9 a on the bottom after the second step in the second step the first semiconductor structure 100 and the second semiconductor structure 1010 are further pressed together as shown in fig1 b to form contact between the top surfaces 920 of cu interconnect 720 of the first semiconductor structure 100 and the interconnect 1020 of the second semiconductor structure 1010 in the meantime shown in fig1 a the top surfaces 910 of the cu vias 820 of the first semiconductor structure 100 have moved down self adaptively when the landing pads 1040 of the second semiconductor structure 1010 are pressed down and the cu interconnects 710 have being bended down to form bended cu interconnects 1210 if there is a void or open between the landing pad of the second wafer.