Memory apparatus using semiconductor devices
View Patent ↗A memory apparatus includes a page including a plurality of memory cells arranged in a column on a substrate. Each of voltages applied to first and second gate conductor layers and first and second impurity layers in each memory cell included in the page is controlled to perform a page write operation of retaining holes, which have been formed through an impact ionization phenomenon or using a gate induced drain leakage current, in a semiconductor base material, or each of voltages applied to the first and second gate conductor layers, third and fourth gate conductor layers, and the first and second impurity layers is controlled to perform a page erase operation of removing the holes from the semiconductor base material, and further lowering a voltage of the semiconductor base material through capacitive coupling with the first gate conductor layer and the second gate conductor layer.
1. A memory apparatus using semiconductor devices, comprising:
a page including a plurality of memory cells arranged in a column on a substrate,
wherein:
each memory cell included in the page has
a semiconductor base material provided on the substrate in a manner standing in an upright position along a vertical direction or extending in a horizontal direction with respect to the substrate,
a first impurity region and a second impurity region at opposite ends of the semiconductor base material,
a gate insulating layer in contact with a side face of the semiconductor base material between the first impurity region and the second impurity region,
a first gate conductor layer partially or entirely covering the gate insulating layer, and
a second gate conductor layer adjacent to the first gate conductor layer and in contact with a side face of the gate insulating layer,
in each of the individual memory cells,
each of voltages applied to the first gate conductor layer, the second gate conductor layer, the first impurity region, and the second impurity region is controlled to allow holes generated through an impact ionization phenomenon or using a gate induced drain leakage current to be retained in the semiconductor base material, and
during a page write operation, a voltage of the semiconductor base material is set to a first data holding voltage that is higher than one or both of a voltage of the first impurity region and a voltage of the second impurity region, and
in all of the individual memory cells forming the page, during a page erase operation,
the voltage of the semiconductor base material is controlled to a voltage higher than the first data holding voltage through one or both of first capacitive coupling between the first gate conductor layer and the semiconductor base material and second capacitive coupling between the second gate conductor layer and the semiconductor base material, and until the voltage of the semiconductor base material has become higher than one or both of the voltage of the first impurity region and the voltage of the second impurity region, the holes are removed from the semiconductor base material through one or both of the first impurity region and the second impurity region, and
the voltage of the semiconductor base material is set to a second data holding voltage lower than the first data holding voltage through the first capacitive coupling and the second capacitive coupling.
2. The memory apparatus using the semiconductor devices according to claim 1 ,
wherein:
during the page erase operation,
a voltage of the first gate conductor layer is changed from a first voltage to a second voltage higher than the first voltage, or a voltage of the second gate conductor layer is changed from a third voltage to a fourth voltage higher than the third voltage,
in a first period, the voltage of the semiconductor base material is controlled to a voltage higher than the first data holding voltage through the first capacitive coupling and the second capacitive coupling,
in a second period, the holes are pulled out from the semiconductor base material through one or both of the first impurity region and the second impurity region until the voltage of the semiconductor base material has become higher than one or both of the voltage of the first impurity region and the voltage of the second impurity region by a built-in voltage, and
in a third period, the voltage of the semiconductor base material is set to the second data holding voltage lower than the first data holding voltage through the first capacitive coupling and the second capacitive coupling.
3. The memory apparatus using the semiconductor devices according to claim 1 , wherein when the page erase operation is performed on the page including the plurality of semiconductor base materials arranged in a column, the page erase operation is concurrently performed on all of the semiconductor base materials included in the page.
4. The memory apparatus using the semiconductor devices according to claim 1 , wherein an inversion layer is not formed in the semiconductor base material in a part of or an entirety of the first period and the second period in which the voltage of the semiconductor base material is changed using one or both of the first capacitive coupling and the second capacitive coupling based on voltages applied to the first impurity region and the second impurity region.
5. The memory apparatus using the semiconductor devices according to claim 1 , wherein a first gate capacitance between the first gate conductor layer and the semiconductor base material is set larger than a second gate capacitance between the second gate conductor layer and the semiconductor base material.
6. The memory apparatus using the semiconductor devices according to claim 1 , wherein the holes are removed from the semiconductor base material through one of the first impurity region or the second impurity region, and another of the first impurity region or the second impurity region is set to a floating state.
7. A memory apparatus using semiconductor devices, comprising a block having arranged therein a plurality of pages each corresponding to the page of the memory apparatus according to claim 1 ,
wherein:
the first impurity region in the memory cell included in each of the plurality of pages connects to a source line, the second impurity region connects to a bit line, one of the first gate conductor layer and the second gate conductor layer connects to a word line, and another of the first gate conductor layer and the second gate conductor layer connects to a first drive control line,
the source line is connected in common to the semiconductor base materials in the block, and
the page erase operation is performed by removing the holes in all of the semiconductor base materials in the selected page in the block based on each of voltages applied to the source line, the bit line, the first drive control line, and the word line.
8. The memory apparatus using the semiconductor devices according to claim 7 , wherein the page erase operation is performed by removing the holes in all of the semiconductor base materials in the plurality of selected pages in the block.
9. The memory apparatus using the semiconductor devices according to claim 1 , wherein one or both of the first gate conductor layer and the second gate conductor layer is/are split into two or more split gate conductor layers as seen in plan view or in the vertical direction, and the split two or more gate conductor layers are operated synchronously or asynchronously.
10. The memory apparatus using the semiconductor devices according to claim 9 , wherein the split gate conductor layers of one of the first gate conductor layer and the second gate conductor layer are arranged on opposite sides of another of the first gate conductor layer or the second gate conductor layer in the vertical direction.