1. A method of measuring bonding quality of a bonded substrate having a top substrate on top of a bottom substrate, the method comprising: creating a plurality of marks at a first side of the top substrate; bonding the top substrate onto the bottom substrate to form the bonded substrate; measuring positions of the plurality of marks; calculating, for each of the plurality of marks, a difference between a measured position and an expected position; and determining delamination areas at an interface between the top substrate and the bottom substrate using the calculated difference.