Memory cell comprising a semiconductor junction diode crystallized adjacent to a silicide
AssigneeSanDisk 3D LLC
InventorS. Brad Herner
Life of this patent
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Abstract
A memory cell is formed of a semiconductor junction diode in series with an antifuse. The cell is programmed by rupture of the antifuse. The semiconductor junction diode comprises silicon, the silicon crystallized in contact with a silicide. The suicide apparently provides a template for crystallization, improving crystallinity and conductivity of the diode, and reducing the programming voltage required to program the cell. It is advantageous to reduce a dielectric layer (such as an oxide, nitride, or oxynitride) intervening between the silicon and the silicon-forming metal during the step of forming the silicide.
Claims6
A method for forming a first memory level of memory cells in a memory array, the method comprising:
- forming a plurality of first conductors at a first height above a substrate in a first pattern and etch step;
- forming a plurality of semiconductor pillars above the first conductors in a second pattern and etch step;
- crystallizing the plurality of first semiconductor pillars, wherein each of the first semiconductor pillars is in contact with a silicide at the time it is crystallized;
- forming a plurality of second conductors above the first semiconductor pillars in a third pattern and etch step;
- and
- forming a plurality of dielectric rupture antifuses between the first and second conductors, each antifuse in series with a first semiconductor pillar of the plurality of first semiconductor pillars, and each antifuse in contact with one of the conductors,
- wherein the first, second, and third pattern and etch steps are all separate.
Dependencies are inferred from the claim text.