Selective Silicon Epitaxy for Advanced Dram Structures

ABSTRACTIn silicon microelectronics, memory cells and chips are used to develop the most advanced technology. In the future these chips will require three dimensional structures to achieve the needed density. This paper describes the use of selective silicon epitaxy to build truly three dimensional DRAM cells. The cell consists of a trench capacitor which is overgrown with single crystal silicon. A transistor and isolation are then built above the trench capacitor resulting in a cell that occupies the same area as the transistor alone. Fully functional memory cells have been built. The results show that selective silicon epitaxy is a realistic candidate for building three dimensional silicon devices.