Semiconductor device, memory device, and electronic device
A memory device in which bit line parasitic capacitance is reduced is provided. The memory device includes a sense amplifier electrically connected to a bit line and a memory cell array stacked over the sense amplifier. The memory cell array includes a plurality of memory cells. The plurality of memory cells are each electrically connected to a bit line. A portion for leading the bit lines is not provided in the memory cell array. Thus, the bit line can be shortened and the bit line parasitic capacitance is reduced.
1. A memory device comprising:
a bit line;
a sense amplifier electrically connected to the bit line;
an input/output circuit stacked below the sense amplifier; and
a memory cell array stacked over the sense amplifier,
wherein the memory cell array includes a memory cell electrically connected to the bit line,
wherein the memory cell includes a write transistor electrically connected to the bit line and a capacitor electrically connected to the write transistor, and
wherein the bit line is not provided over the write transistor.
2. The memory device according to claim 1 , wherein a semiconductor layer of the write transistor includes a metal oxide.
3. An electronic device comprising the memory device according to claim 1 .
4. A memory device comprising:
a sense amplifier block including a bit line and a sense amplifier electrically connected to the bit line;
an input/output circuit stacked below the sense amplifier; and
a memory cell array stacked over the sense amplifier block,
wherein the memory cell array includes a conductor and a memory cell,
wherein the memory cell includes:
a write transistor electrically connected to the bit line through the conductor; and
a capacitor electrically connected to the write transistor, and
wherein the conductor includes a portion in contact with a bottom surface of a semiconductor layer of the write transistor.
5. The memory device according to claim 4 , wherein the semiconductor layer of the write transistor includes a metal oxide.
6. An electronic device comprising the memory device according to claim 4 .