Semiconductor-element-including memory device
View Patent ↗A memory device includes pages including memory cells arranged on a substrate. Voltages applied to first and second gate conductor layers and first and second impurity regions in each memory cell are controlled to retain a group of positive holes. The first and second impurity regions and first and second gate conductor layers are connected to source, bit, plate, and word lines. In a page write operation, a channel semiconductor layer is at a first data retention voltage. In a page erase operation, the group of positive holes are discharged by controlling the voltages, the channel semiconductor layer is at a second data retention voltage, a positive voltage pulse is applied to at least one of the word and plate lines of a selected page, and a ground voltage is applied to the word and plate lines of a non-selected page and to all of the source and bit lines.
1. A semiconductor-element-including memory device that is a memory device in which in plan view on a substrate, a plurality of pages are arranged in a column direction, each of the pages being constituted by a plurality of memory cells arranged in a row direction,
each memory cell included in each of the pages comprising:
a semiconductor body that stands on the substrate in a vertical direction relative to the substrate or that extends along the substrate in a horizontal direction relative to the substrate;
a first impurity region and a second impurity region that are disposed at respective ends of the semiconductor body;
a gate insulator layer that partially or entirely surrounds a side surface of the semiconductor body; and
a first gate conductor layer and a second gate conductor layer that cover the gate insulator layer and that are disposed adjacent to each other, wherein
voltages applied to the first gate conductor layer, the second gate conductor layer, the first impurity region, and the second impurity region are controlled to retain a group of positive holes, generated by an impact ionization phenomenon, inside the semiconductor body,
in a page write operation, a voltage of the semiconductor body is made equal to a first data retention voltage that is higher than the voltage of one of the first impurity region or the second impurity region or that is higher than the voltages of both of the first impurity region and the second impurity region,
in a page erase operation, the group of positive holes in the semiconductor body are made to be extinct by controlling the voltages applied to the first impurity region, the second impurity region, the first gate conductor layer, and the second gate conductor layer, and the voltage of the semiconductor body is made equal to a second data retention voltage that is lower than the first data retention voltage,
the first impurity region of each memory cell is connected to a source line, the second impurity region thereof is connected to a corresponding one of bit lines, one of the first gate conductor layer or the second gate conductor layer thereof is connected to a corresponding one of word lines, and the other of the first gate conductor layer or the second gate conductor layer thereof is connected to a corresponding one of plate lines, and
in the page erase operation, a positive voltage pulse is applied to one or both of the word line and the plate line of a page, among the pages, for which selective erasing is performed, a ground voltage is applied to the word line and the plate line of a non-selected page among the pages, and the ground voltage is applied to all of the source line and the bit lines.
2. The semiconductor-element-including memory device according to claim 1 , wherein
in plan view, the word lines and the plate lines are disposed parallel to the pages, and
the bit lines are disposed in a direction perpendicular to the pages.
3. The semiconductor-element-including memory device according to claim 1 , wherein
a first gate capacitance between the semiconductor body and the first gate conductor layer or the second gate conductor layer to which the plate line is connected is larger than a second gate capacitance between the semiconductor body and the first gate conductor layer or the second gate conductor layer to which the word line is connected.
4. The semiconductor-element-including memory device according to claim 1 , wherein
the ground voltage is zero volts.
5. The semiconductor-element-including memory device according to claim 1 , wherein
in plan view, the source line includes isolated source lines that are disposed for respective groups of memory cells arranged in the column direction and that are disposed parallel to the word lines and the plate lines.
6. The semiconductor-element-including memory device according to claim 1 , wherein
in plan view, the source line is disposed so as to be shared between pages adjacent to each other.
7. The semiconductor-element-including memory device according to claim 1 , wherein
in plan view, the plate lines include a plate line that is disposed so as to be shared between at least two or more pages adjacent to each other.
8. The semiconductor-element-including memory device according to claim 1 , wherein
the semiconductor body is P-type silicon, and the first impurity region and the second impurity region are N-type silicon.
9. The semiconductor-element-including memory device according to claim 1 , wherein
in the page erase operation, selective erasing is performed for at least two pages.
10. The semiconductor-element-including memory device according to claim 1 , wherein
the word lines and the plate lines are connected to a row decoder circuit, the row decoder circuit receives a row address, and the page is selected in accordance with the row address.
11. The semiconductor-element-including memory device according to claim 1 , wherein
the bit lines are connected to a sense amplifier circuit, the sense amplifier circuit is connected to a column decoder circuit, the column decoder circuit receives a column address, and the sense amplifier circuit is selectively connected to an input/output circuit in accordance with the column address.
12. The semiconductor-element-including memory device according to claim 1 , wherein
in a direction in which the semiconductor body extends, at least one of the first gate conductor layer or the second gate conductor layer is or both of the first gate conductor layer and the second gate conductor layer are each divided into two or more gate conductor layers, and at least two of the divided gate conductor layers are connected to the word line and the plate line.
13. The semiconductor-element-including memory device according to claim 1 , wherein
the first gate conductor layer or the second gate conductor layer connected to the word line is divided into a third gate conductor layer and a fourth gate conductor layer,
the third gate conductor layer or the fourth gate conductor layer is disposed on both sides of the first gate conductor layer or the second gate conductor layer that is not divided, and
a voltage identical to a voltage applied to the word line is applied to at least one of the third gate conductor layer or the fourth gate conductor layer.