ROM embedded DRAM with dielectric removal/short
AssigneeMicron Technology, Inc.
InventorsPhillip G. Wald, Casey Kurth, Scott Derner
Life of this patent
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Abstract
A ROM embedded DRAM allows hard programming of ROM cells by shorting DRAM capacitor plates during fabrication. In one embodiment, the intermediate dielectric layer is removed and the plates are shorted with a conductor. In another embodiment, an upper conductor and dielectric are removed and a conductor is fabricated in contact with the DRAM storage plate. The memory allows ROM cells to be hard programmed to different data states, such as Vcc and Vss.
Claims15
A method of fabricating an integrated circuit read only memory (ROM) cell comprising:
- fabricating the first conductor layer vertically above a substrate;
- fabricating a dielectric layer over the first conductor layer;
- fabricating a second conductor layer over the dielectric layer;
- selectively removing a portion of the second conductor layer and the dielectric layer to expose the first conductor plate;
- and
- electrically coupling the exposed first conductor to receive a program voltage.
A method of fabricating an integrated circuit read only memory (ROM) cell comprising:
- fabricating the first conductor layer vertically above a substrate;
- fabricating a dielectric layer over the first conductor layer;
- fabricating a second conductor layer over the dielectric layer;
- selectively etching a portion of the second conductor layer and the dielectric layer to form a plug opening and expose the first conductor plate;
- and
- forming a conductive plug in the plug opening to electrically couple the first conductor to receive a program voltage.
A method of fabricating a memory device comprising:
- fabricating first and second capacitors;
- removing dielectric material from the first capacitor;
- coupling a storage node of the first capacitor to a voltage source node;
- forming a first access transistor to couple the storage node of the first capacitor to a digit line;
- and
- forming a second access transistor to couple the second capacitor to the digit line.
Dependencies are inferred from the claim text.