Packaging structure of substrates connected by metal terminals
A packaging structure includes a first substrate including a first metal terminal and a second metal terminal whose height is lower than the height of the first metal terminal; and a second substrate including a third metal terminal and a fourth metal terminal whose height is lower than the height of the third metal terminal, the second substrate being provided on the first substrate, the first metal terminal and the third metal terminal being directly bonded with each other, and the second metal terminal and the fourth metal terminal being bonded via a connection portion.
1. A packaging structure comprising:
a first substrate including a first metal terminal and a second metal terminal whose height is lower than the height of the first metal terminal, the first metal terminal and the second metal terminal being formed at a first planar surface of the first substrate; and
a second substrate including a third metal terminal and a fourth metal terminal whose height is lower than the height of the third metal terminal, the third metal terminal and the fourth metal terminal being formed at a second planar surface of the second substrate, the third metal terminal being made of the same kind of metal as the first metal terminal,
the second substrate being provided on the first substrate such that the second planar surface of the second substrate faces the first planar surface of the first substrate,
only the first metal terminal and the third metal terminal being directly bonded with each other, while the second metal terminal and the fourth metal terminal are bonded via a connection portion.
2. The packaging structure according to claim 1 , further comprising a plurality of the second metal terminals and a plurality of the fourth metal terminals,
wherein the plurality of second metal terminals and the plurality of fourth metal terminals are provided at an area that is an outer periphery side of an area at which the first metal terminal and the third metal terminal are provided, in a plan view.
3. The packaging structure according to claim 2 ,
wherein each of the first substrate and the second substrate is rectangular, in a plan view, and
wherein all of or a part of the second metal terminals and all of or a part of the fourth metal terminals are placed on a diagonal line of the rectangular of the first substrate and the second substrate, respectively, in a plan view.
4. The packaging structure according to claim 1 , wherein the second metal terminal and the fourth metal terminal are made of the same kind of metal as the first metal terminal and the third metal terminal.
5. The packaging structure according to claim 1 , wherein the connection portion is made of solder whose melting point is less than 200° C.
6. The packaging structure according to claim 1 , wherein the planar size of each of the second metal terminal and the fourth metal terminal is larger than the planar size of each of the first metal terminal and the third metal terminal, respectively.