Stacked MOS devices with polysilicon interconnects.

摘要

A stacked metal-oxide-semiconductor (MOS) device has a lower source (18), drain (20) and channel (34) formed in a silicon substrate (12) and an upper source (30), drain (32) and channel (36) formed in a deposited polysilicon layer (28) which is recrystallized by laser annealing. Instead of the conventional method of depositing aluminum interconnects between the device upper terminals and bonding pads, interconnect parts (29) are formed in the recrystallized polysilicon layer (28) itself. This has the advantages of preventing junction distortion by undesired aluminum penetration into the silicon. Also contact windows do not have to be opened directly to the source and drain terminals thereby easing desing constraints.