Connection structure and semiconductor device comprising the same

A semiconductor device comprising:

• a first substrate;
• a second substrate arranged on the first substrate;
• and
• a conductive interconnection node electrically connecting the first substrate to the second substrate,
• wherein the conductive interconnection node includes:
• a pad formed in the first substrate and containing nickel,
• a bump connection layer formed in the second substrate and containing nickel, and
• a solder bump arranged between the pad and the bump connection layer, the solder bump including:
• a first intermetallic compound contacting the pad and containing copper, and
• a second intermetallic compound contacting the bump connection layer and containing copper.

A semiconductor device comprising:

• a package substrate;
• a logic die arranged on the package substrate;
• a plurality of memory dies sequentially stacked on the logic die,
• wherein the plurality of memory dies include a first die and a second die, which are stacked;
• and
• a conductive connection node between and electrically connecting the first die to the second die,
• wherein the conductive connection node includes:
• a pad formed at a surface of the first die and containing nickel,
• a bump connection layer formed at a surface of the second die and containing nickel, and
• a solder bump arranged between the pad and the bump connection layer, wherein the solder bump includes:
• a first intermetallic compound portion including a first intermetallic compound including copper and contacting the pad, and
• a second intermetallic compound portion including the first intermetallic compound including copper or a second intermetallic compound including iron or lead, and contacting the bump connection layer.