| abstract |
A die stack structure includes a first die and a second die. The first die and the second die are bonded together by a hybrid bonding structure. At least one of the first test pad of the first die or the second test pad of the second die has a protrusion, and a bonding insulating layer of the hybrid bonding structure covers and contacts the first test The protrusion of the at least one of the pad or the second test pad is such that the first test pad and the second test pad are electrically isolated from each other. |