Patent ID: 7811932

Claim:
A method of forming a die-on-die assembly, forming a first external contact on a first semiconductor die; forming a first seed layer over the first semiconductor die including over the first external contact; forming a first photoresist layer over the first seed layer having a first opening and a second opening, wherein the first opening is over the first external contact; performing a plating step to cause formation of a first plated contact in the first opening and a peg in the second opening; removing the first photoresist layer; removing the first seed layer in areas adjacent to the first plated contact and the peg; forming a second external contact on a second semiconductor die; forming a second seed layer over the second semiconductor die including over the second external contact; forming a second photoresist layer over the second seed layer having a third opening and a ring opening, wherein the third opening is over the second external contact; performing a plating step to cause formation of a second plated contact in the third opening and a containing feature in the ring opening useful in defining a contained area useful in constraining movement between the first semiconductor die and the second semiconductor die; removing the second photoresist layer; removing the second seed layer in areas adjacent to the second plated contact and the containing feature; and placing the first semiconductor die in contact with the second semiconductor die such that the first plated contact is in contact with the second plated contact and the peg is within the contained area.