Peripheral circuits of three-dimensional mask-programmable memory
View Patent ↗The present invention discloses several preferred mask-programmable 3-D memory (3D-MPROM) structures, including pillar-shaped 3D-MPROM, natural-junction 3D-MPROM, interleaved 3D-MPROM, and separate 3D-MPROM. The present invention also makes further improvements to its peripheral circuits. The use of sense-amplifier can significantly lower the leakage-current requirement on the 3D-ROM memory cell. Self-timing can improve the 3D-ROM speed and reduce its power consumption.
1. A three-dimensional mask-programmable read-only memory (3D-MPROM), comprising:
a semiconductor substrate comprising a plurality of transistor-based differential sense-amplifiers with first and second inputs;
a plurality of 3D-MPROM levels stacked above said semiconductor substrate, said 3D-MPROM levels comprising a plurality of diode-based memory cells, at least one diode-based dummy memory cell and a plurality of address-select lines;
a plurality of contact vias coupling said address-select lines in said 3D -MPROM levels and said substrate;
wherein said first input is coupled to selected one of said diode-based memory cells through a first selected contact via, and said second input is coupled to said diode-based dummy memory cell through a second selected contact via.
2. The 3D-MPROM according to claim 1 , wherein said sense-amplifiers further comprise an S/A-enable (SE) signal, whereby said sense-amplifiers amplify read-out signals from selected ones of said diode-based memory cells when said SE signal is asserted.
3. The 3D-MPROM according to claim 2 , further comprising:
a first timing bit line in said 3D-MPROM levels;
a first timing sense-amplifier in said semiconductor substrate and coupled to said first timing bit line;
whereby the output from said first timing sense-amplifier asserts said SE signal and starts data sampling.
4. The 3D-MPROM according to claim 2 , further comprising:
a second timing bit line in said 3D-MPROM levels;
a second timing sense-amplifier in said semiconductor substrate and coupled to said second timing bit line;
whereby the output from said second timing sense-amplifier de-asserts said SE signal and stops data sampling.
5. The 3D-MPROM according to claim 1 , wherein the read voltage (V R ) applied to said diode-based memory cells is larger than the supply voltage of said 3D-MPROM.
6. The 3D-MPROM according to claim 5 , further comprising a V R -generating block in said semiconductor substrate.