Patent ID: 7858497
Filing Date: 2010-12-28
Classification: H01L

Abstract:
1. A stacked device manufacturing method for manufacturing a plurality of individual stacked devices by stacking a plurality of wafers to form a stacked wafer and next dividing said stacked wafer into said individual stacked devices along a plurality of crossing streets formed on the front side of each wafer, wherein each wafer has a plurality of devices respectively formed in a plurality of regions partitioned by said streets and a plurality of electrodes extending from the front side to the back side of each region, said stacked device manufacturing method comprising: a kerf forming step of forming a kerf on the front side of each wafer along each street prior to grinding the back side of each wafer to thereby reduce the thickness of each wafer to a predetermined finished thickness, said kerf having a depth corresponding to said predetermined finished thickness from the front side of each wafer; a first stacking step of stacking a first one of said wafers and a second one of said wafers after performing said kerf forming step in such a manner that the front side of said second wafer is opposed to the front side of said first wafer and that said electrodes of said second wafer are respectively bonded to said electrodes of said first wafer; a first back grinding step of grinding the back side of said second wafer to expose each kerf of said second wafer to the back side of said second wafer after performing said first stacking step; a second stacking step of stacking a third one of said wafers subjected to said kerf forming step to said second wafer after performing said first back grinding step in such a manner that the front side of said third wafer is opposed to the back side of said second wafer and that said electrodes of said third wafer are respectively bonded to said electrodes of said second wafer; a second back grinding step of grinding the back side of said third wafer to expose each kerf of said third wafer to the back side of said third wafer after performing said second stacking step; and a third back grinding step of grinding the back side of said first wafer to expose each kerf of said first wafer to the back side of said first wafer after performing said second back grinding step.