Embodiments of three-dimensional (3D) memory devices having a shielding layer and methods for forming the 3D memory devices are disclosed. In an example, a method for forming a 3D memory device is disclosed. A peripheral device is formed on a substrate. A first interconnect layer including a first plurality of interconnects is formed above the peripheral device. A shielding layer including a conduction region is formed above the first interconnect layer. A second interconnect layer including a second plurality of interconnects is formed above the shielding layer. The conduction region of the shielding layer covers an area of the first and second plurality of interconnects in the first and second interconnect layers. A plurality of memory strings each extending vertically above the second interconnect layer are formed.

A semiconductor storage device includes a first wiring, a second wiring, an insulating portion, and a resistance changing film. The first wiring extends in a first direction. The second wiring extends in a second direction intersecting the first direction, and is provided at a location different from that of the first wiring in a third direction intersecting the first direction and the second direction. The insulating portion is provided between the first wiring and the second wiring in the third direction. The resistance changing film is provided between the first wiring and the second wiring in the third direction, is adjacent to the insulating film from a first side and a second side which is opposite to the first side in the first direction, and the resistance changing film being smaller than the second wiring in the first direction.

A semiconductor storage device includes a first wiring, a second wiring, an insulating portion, and a resistance changing film. The first wiring extends in a first direction. The second wiring extends in a second direction intersecting the first direction, and is provided at a location different from that of the first wiring in a third direction intersecting the first direction and the second direction. The insulating portion is provided between the first wiring and the second wiring in the third direction. The resistance changing film is provided between the first wiring and the second wiring in the third direction, is adjacent to the insulating film from a first side and a second side which is opposite to the first side in the first direction, and the resistance changing film being smaller than the second wiring in the first direction.

Some embodiments include apparatuses and methods of forming the apparatuses. One of the apparatus includes a first conductive contact; a second conductive contact; levels of conductive materials stacked over one another and located over the first and second conductive contacts; levels of dielectric materials interleaved with the levels of the conductive materials, the levels of conductive materials and the levels of dielectric materials formed a stack of materials; a first conductive structure located on a first side of the stack of materials and contacting the first conductive contact and a first level of conductive material of the levels of conductive materials; and a second conductive structure located on a second side of the stack of materials and contacting the second conductive contact and a second level of conductive material of the levels of conductive materials.

Some embodiments include apparatuses and methods of forming the apparatuses. One of the apparatus includes a first conductive contact; a second conductive contact; levels of conductive materials stacked over one another and located over the first and second conductive contacts; levels of dielectric materials interleaved with the levels of the conductive materials, the levels of conductive materials and the levels of dielectric materials formed a stack of materials; a first conductive structure located on a first side of the stack of materials and contacting the first conductive contact and a first level of conductive material of the levels of conductive materials; and a second conductive structure located on a second side of the stack of materials and contacting the second conductive contact and a second level of conductive material of the levels of conductive materials.

A semiconductor memory device includes: a stacked structure including first and second select patterns spaced apart from each other in a first direction; a gate isolation layer extending in a second direction intersecting the first direction between the first and second select patterns; channel structures penetrating the stack structure; and first and second bit lines extending in the first direction, the first and second bit lines being adjacent to each other. The channel structures include: a first channel structure which penetrates the first select pattern and is spaced apart by a first distance from the gate isolation layer in the first direction; and a second channel structure which penetrates the second select pattern and is spaced apart by substantially the first distance from the gate isolation layer in the first direction. The first and second channel structures are respectively connected to the second and first bit lines.

A semiconductor memory device includes: a stacked structure including first and second select patterns spaced apart from each other in a first direction; a gate isolation layer extending in a second direction intersecting the first direction between the first and second select patterns; channel structures penetrating the stack structure; and first and second bit lines extending in the first direction, the first and second bit lines being adjacent to each other. The channel structures include: a first channel structure which penetrates the first select pattern and is spaced apart by a first distance from the gate isolation layer in the first direction; and a second channel structure which penetrates the second select pattern and is spaced apart by substantially the first distance from the gate isolation layer in the first direction. The first and second channel structures are respectively connected to the second and first bit lines.

Memory devices may include a source region, channels, a gate insulation layer pattern, a selection gate pattern, a first gate pattern, a second gate pattern and a drain region. The source region may include first impurities having a first conductivity type at an upper portion of a substrate. The channels may contact the source region. Each of the channels may extend in a vertical direction that is perpendicular to an upper surface of the substrate. The selection gate pattern may be on sidewalls of the channels. The first gate pattern may be on the sidewalls of the channels. The first gate pattern may be a common electrode of all of multiple channels. The second gate patterns may be on the sidewalls of the channels. The drain region may include second impurities having a second conductivity type that is different from the first conductivity type at an upper portion of each of the channels.

Memory devices may include a source region, channels, a gate insulation layer pattern, a selection gate pattern, a first gate pattern, a second gate pattern and a drain region. The source region may include first impurities having a first conductivity type at an upper portion of a substrate. The channels may contact the source region. Each of the channels may extend in a vertical direction that is perpendicular to an upper surface of the substrate. The selection gate pattern may be on sidewalls of the channels. The first gate pattern may be on the sidewalls of the channels. The first gate pattern may be a common electrode of all of multiple channels. The second gate patterns may be on the sidewalls of the channels. The drain region may include second impurities having a second conductivity type that is different from the first conductivity type at an upper portion of each of the channels.

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.