The present disclosure relates to circuits, systems, and methods of operation for a memory device. In an example, a memory device includes a memory array including a plurality of memory cells, each memory cell having an impedance that varies in accordance with a respective data value stored therein; and a tracking memory cell having an impedance based on a tracking data value stored therein; and a read circuit coupled to the memory array, the read circuit configured to determine an impedance of a selected memory cells with respect to the impedance of the tracking memory cell; read a data value stored within the selected memory cell based upon a voltage change of a signal node voltage corresponding to the impedance of the selected memory cell.

The present disclosure relates to circuits, systems, and methods of operation for a memory device. In an example, a memory device includes a memory array including a plurality of memory cells, each memory cell having an impedance that varies in accordance with a respective data value stored therein; and a tracking memory cell having an impedance based on a tracking data value stored therein; and a read circuit coupled to the memory array, the read circuit configured to determine an impedance of a selected memory cells with respect to the impedance of the tracking memory cell; read a data value stored within the selected memory cell based upon a voltage change of a signal node voltage corresponding to the impedance of the selected memory cell.

A memory device includes pages, each being composed of a plurality of memory cells arrayed on a substrate in row form, and controls voltages to be applied to a first gate conductor layer, a second gate conductor layer, a first impurity layer, and a second impurity layer of each of the memory cells included in the pages to perform a page write operation of holding a hole group generated by an impact ionization phenomenon or a gate induced drain leakage current in a channel semiconductor layer, and controls voltages to be applied to the first gate conductor layer, the second gate conductor layer, the third gate conductor layer, the fourth gate conductor layer, the first impurity layer, and the second impurity layer to perform a page erase operation of removing the hole group out of the channel semiconductor layer. The first impurity layer of the each of the memory cells is connected to a source line, the second impurity layer is connected to a bit line, one of the first gate conductor layer and the second gate conductor layer is connected to one of word lines, and the other is connected to a first driving control line. The first driving control line is provided in common for adjacent ones of the pages, and when in the page erase operation, the memory device applies pulsed voltages to one of the word lines which performs the page erase operation and the first driving control line, and applies a fixed voltage to another one of the word lines which is not selected to perform the page erase operation.

In a memory device, pages are arrayed in a column direction, each page constituted by memory cells arrayed in row direction on an insulating substrate. Each memory cell includes a zonal P layer. N.sup.+ layers continuous with a source line and a bit line respectively are on both sides of the P layer. Gate insulating layers surround part of the P layer continuous with the N.sup.+ layer and part of the P layer continuous with the N.sup.+ layer 3b, respectively. One side surface and the other side surface of the gate insulating layer are covered with a gate conductor layer continuous with a first plate line and a gate conductor layer continuous with a second plate line, respectively. A gate conductor layer continuous with a word line surrounds the gate insulating layer.

In a memory device, pages are arrayed in a column direction, each page constituted by memory cells arrayed in row direction on an insulating substrate. Each memory cell includes a zonal P layer. N.sup.+ layers continuous with a source line and a bit line respectively are on both sides of the P layer. Gate insulating layers surround part of the P layer continuous with the N.sup.+ layer and part of the P layer continuous with the N.sup.+ layer 3b, respectively. One side surface and the other side surface of the gate insulating layer are covered with a gate conductor layer continuous with a first plate line and a gate conductor layer continuous with a second plate line, respectively. A gate conductor layer continuous with a word line surrounds the gate insulating layer.

A memory device includes pages, each being composed of a plurality of memory cells arrayed on a substrate in row form. The memory device controls voltages to be applied to a first gate conductor layer, a second gate conductor layer, a first impurity region, and a second impurity region of each of the memory cells included in the pages to perform a page write operation of holding a hole group formed by an impact ionization phenomenon or a gate induced drain leakage current in a channel semiconductor layer, and controls voltages to be applied to the first gate conductor layer, the second gate conductor layer, the third gate conductor layer, the fourth gate conductor layer, the first impurity region, and the second impurity region to perform a page erase operation of removing the hole group out of the channel semiconductor layer. The first impurity layer of each of the memory cells is connected to a source line, the second impurity region is connected to a bit line, one of the first gate conductor layer and the second gate conductor layer is connected to a word line, and the other is connected to a first driving control line. The bit line is connected to a sense amplifier circuit via a switching circuit. When in a page read operation, the memory device reads page data in a memory cell group selected by the word line to the bit line, and performs charge sharing between the bit line and a charge sharing node of the switching circuit opposite to the bit line to accelerate a read determination by the sense amplifier circuit.

A memory device includes pages, each being composed of a plurality of memory cells arrayed on a substrate in row form. The memory device controls voltages to be applied to a first gate conductor layer, a second gate conductor layer, a first impurity region, and a second impurity region of each of the memory cells included in the pages to perform a page write operation of holding a hole group formed by an impact ionization phenomenon or a gate induced drain leakage current in a channel semiconductor layer, and controls voltages to be applied to the first gate conductor layer, the second gate conductor layer, the third gate conductor layer, the fourth gate conductor layer, the first impurity region, and the second impurity region to perform a page erase operation of removing the hole group out of the channel semiconductor layer. The first impurity layer of each of the memory cells is connected to a source line, the second impurity region is connected to a bit line, one of the first gate conductor layer and the second gate conductor layer is connected to a word line, and the other is connected to a first driving control line. The bit line is connected to a sense amplifier circuit via a switching circuit. When in a page read operation, the memory device reads page data in a memory cell group selected by the word line to the bit line, and performs charge sharing between the bit line and a charge sharing node of the switching circuit opposite to the bit line to accelerate a read determination by the sense amplifier circuit.

Provided on a substrate are an N.sup.+ layer connecting to a source line SL and an N.sup.+ layer connecting to a bit line BL that are located at opposite ends of a Si pillar standing in an upright position along the vertical direction, an N layer continuous with the N.sup.+ layer, an N layer continuous with the N.sup.+ layer, a first gate insulating layer surrounding the Si pillar, a first gate conductor layer surrounding the first gate insulating layer and connecting to a plate line PL, and a second gate conductor layer surrounding a second gate insulating layer surrounding the Si pillar and connecting to a word line WL. A voltage applied to each of the source line SL, the plate line PL, the word line WL, and the bit line BL is controlled to perform a data retention operation for retaining holes, which have been generated through an impact ionization phenomenon or using a gate induced drain leakage current, in a channel region of the Si pillar, and a data erase operation for removing the holes from the channel region.

There are provided the steps of forming an N.sup.+ layer 21a and a Si pillar 26 on a substrate 20, the N.sup.+ layer 21a being connected to a source line SL, the Si pillar 26 standing in a vertical direction and being composed of a P.sup.+ layer 22a in a center portion thereof and a P layer 25a surrounding the P.sup.+ layer 22a; forming an N.sup.+ layer 3b and HfO.sub.2 layers 28a and 28b of gate insulating layers on the P.sup.+ layer 22a, the N.sup.+ layer 3b being connected to a bit line BL, the HfO.sub.2 layers 28a and 28b surrounding the Si pillar 26; and forming a TiN layer 30a of a gate conductor layer and a TiN layer 30b of a gate conductor layer, the TiN layer 30a surrounding the HfO.sub.2 layer 28a and being connected to a plate line PL, the TiN layer 30b surrounding the HfO.sub.2 layer 28b and being connected to a word line WL. Voltages to be applied to the source line SL, the plate line PL, the word line WL, and the bit line BL are controlled to perform a data write operation for holding a hole group generated by an impact ionization phenomenon or a gate induced drain leakage current in the Si pillar 26 and a data erase operation for discharging the hole group from within the Si pillar 26.

There are provided the steps of forming an N.sup.+ layer 21a and a Si pillar 26 on a substrate 20, the N.sup.+ layer 21a being connected to a source line SL, the Si pillar 26 standing in a vertical direction and being composed of a P.sup.+ layer 22a in a center portion thereof and a P layer 25a surrounding the P.sup.+ layer 22a; forming an N.sup.+ layer 3b and HfO.sub.2 layers 28a and 28b of gate insulating layers on the P.sup.+ layer 22a, the N.sup.+ layer 3b being connected to a bit line BL, the HfO.sub.2 layers 28a and 28b surrounding the Si pillar 26; and forming a TiN layer 30a of a gate conductor layer and a TiN layer 30b of a gate conductor layer, the TiN layer 30a surrounding the HfO.sub.2 layer 28a and being connected to a plate line PL, the TiN layer 30b surrounding the HfO.sub.2 layer 28b and being connected to a word line WL. Voltages to be applied to the source line SL, the plate line PL, the word line WL, and the bit line BL are controlled to perform a data write operation for holding a hole group generated by an impact ionization phenomenon or a gate induced drain leakage current in the Si pillar 26 and a data erase operation for discharging the hole group from within the Si pillar 26.