Semiconductor device, imaging device and semiconductor device manufacturing method
A semiconductor device manufacturing method includes a wafer stack manufacturing process and a dicing process. The wafer stack manufacturing process includes: a first wafer manufacturing process of manufacturing a resin film covering circuits and heated to a temperature higher than a glass transition point of the resin film, manufacturing first holes extending from a surface of the resin film to wirings of the circuits, and providing electrodes electrically connected to the wirings in the first holes to form a first wafer; a second wafer manufacturing process of manufacturing a resin film covering circuits and heated to a temperature lower than a glass transition point of the resin film, manufacturing second holes extending from a surface of the resin film to wirings of the circuits, and providing the electrodes electrically connected to the wirings in the second holes to form a second wafer; and a wafer bonding process.
1. A semiconductor device manufacturing method comprising:
a wafer stack manufacturing process of manufacturing a wafer stack in which a plurality of wafers comprising circuits and electrodes electrically connected to the circuits are stacked; and
a dicing process of dicing the wafer stack,
wherein the wafer stack manufacturing process comprises:
a first wafer manufacturing process of manufacturing a resin film covering the plurality of circuits and heated to a temperature higher than a glass transition point of the resin film, manufacturing first holes extending from a surface of the resin film to wirings of the circuits, and providing the electrodes electrically connected to the wirings in the first holes to form a first wafer;
a second wafer manufacturing process of manufacturing a resin film covering the plurality of circuits and heated to a temperature lower than a glass transition point of the resin film, manufacturing second holes extending from a surface of the resin film to wirings of the circuits, and providing the electrodes electrically connected to the wirings in the second holes to form a second wafer; and
a wafer bonding process of causing respective electrode sides of the first wafer and the second wafer to be opposite to each other, bonding the respective resin films together by heating the resin film of the second wafer to a temperature higher than the glass transition point, and bonding the respective electrodes together to form a stack of the first wafer and the second wafer constituting at least a part of the wafer stack.
2. The semiconductor device manufacturing method according to claim 1 ,
wherein, in a cross section including a lamination direction in which the plurality of wafers are stacked, a length of surfaces of the electrodes of the first wafer on a bonding-portion side between the electrodes of the first wafer and the electrodes of the second wafer is shorter than a length of surfaces of the electrodes of the second wafer on the bonding-portion side.
3. The semiconductor device manufacturing method according to claim 1 ,
wherein, when the semiconductor device is viewed in a lamination direction in which the plurality of wafers are stacked, surfaces of the electrodes of the first wafer on a bonding-portion side between the electrodes of the first wafer and the electrodes of the second wafer are formed in edge portions of surfaces of the electrodes of the second wafer on the bonding-portion side.