A 3D semiconductor device including: a first single crystal layer with first transistors; overlaid by a first metal layer; a second metal layer overlaying the first metal layer and being overlaid by a third metal layer; a logic gates including at least the first metal layer interconnecting the first transistors; second transistors disposed atop the third metal layer; third transistors disposed atop the second transistors; a top metal layer disposed atop the third transistors; and a memory array including word-lines, and at least four memory mini arrays, where each of the memory mini arrays includes at least four rows by four columns of memory cells, where each of the memory cells includes at least one of the second transistors or third transistors, sense amplifier circuit(s) for each of the memory mini arrays, the second metal layer provides a greater current carrying capacity than the third metal layer.

According to one embodiment, a semiconductor memory device includes: a first chip including first conductive layers arranged at intervals in a first direction, a first semiconductor layer extending through an inside of the first conductive layers in the first direction, a first insulating film between the first semiconductor layer and the first conductive layers, a second semiconductor layer provided above the first conductive layers and in contact with the first semiconductor layer, and a first electrode provided in contact with an upper side of the second semiconductor layer; and a second chip including a second electrode in contact with the first electrode, and a second conductive layer in contact with the second electrode.

A 3D semiconductor device, the device including: a first level including a plurality of first metal layers; a second level, where the second level overlays the first level, where the second level includes at least one single crystal silicon layer, where the second level includes a plurality of transistors, where each transistor of the plurality of transistors includes a single crystal channel, where the second level includes a plurality of second metal layers, where the plurality of second metal layers include interconnections between the transistors of the plurality of transistors, where the second level is overlaid by a first isolation layer; and a connective path between the plurality of transistors and the plurality of first metal layers, where the connective path includes a via disposed through at least the single crystal silicon layer, and where at least one of the plurality of transistors includes a gate all around structure.

Provided is a method of forming a three-dimensional (3D) memory device including: forming a discharging layer and a stack structure on a buffer layer; forming vertical channel structures in the stack structure; forming an opening in the stack structure, wherein the opening includes two first trenches extending along a X direction and two second trenches extending along a Y direction, and the two first trenches and the two second trenches are separated from each other; forming an insulating layer on a sidewall of the opening; removing the discharging layer exposed by the insulating layer to form a cavity connecting the two first trenches and the two second trenches, thereby forming a ring-shaped opening; performing a gate replacement process to replace sacrificial layers of the stack structure by conductive layers; and filling an isolating material in the ring-shaped opening to form an isolating ring structure.

Provided is a three-dimensional flash memory including a substrate, a stack structure, a stop layer, two slit trenches, a plurality of vertical channel structures, and a plurality of slit holes. The stack structure is disposed on the substrate. The stack structure includes a plurality of dielectric layers and a plurality of conductive layers stacked alternately. The stop layer is disposed between the substrate and the stack structure. The two slit trenches penetrate through the stack structure to expose the stop layer. The vertical channel structures are disposed between the two slit trenches and penetrate through the stack structure and the stop layer. The slit holes are discretely disposed between the vertical channel structures, and penetrate through the stack structure to expose the stop layer. A method of forming the three-dimensional flash memory is also provided.

Algorithms for fast data retrieval, low power consumption in a 3D or planar non-volatile array of memory cells, connected between an accessible drain string and a floating, not directly accessible, source string, in a NOR-logic type of architecture, are presented.

A memory device includes a transistor and a memory cell. The transistor includes a first gate electrode, a second gate electrode, a channel layer, and a gate dielectric layer. The second gate electrode is over the first gate electrode. The channel layer is located between the first gate electrode and the second gate electrode. The gate dielectric layer is located between the channel layer and the second gate electrode. The memory cell is sandwiched between the first gate electrode and the channel layer.

A memory circuit includes: (i) a semiconductor substrate having a planar surface, the semiconductor substrate having formed therein circuitry for memory operations; (ii) a memory array formed above the planar surface, the memory array having one or more electrodes to memory circuits in the memory array, the conductors each extending along a direction substantially parallel to the planar surface; and (iii) one or more transistors each formed above, alongside or below a corresponding one of the electrodes but above the planar surface of the semiconductor substrate, each transistor (a) having first and second drain/source region and a gate region each formed out of a semiconductor material, wherein the first drain/source region, the second drain/source region or the gate region has formed thereon a metal silicide layer; and (b) selectively connecting the corresponding electrode to the circuitry for memory operations.

Carbon has many advantageous uses as a sacrificial material in the fabricating thin-film storage transistors, such as those organized as NOR memory strings. In one implementation, the carbon layers are replaced by heavily doped n-type polysilicon source and drain regions at a late step during device fabrication. As a result, many high temperature steps within the fabrication process may now be carried out without concern for thermal diffusion from the heavily doped polysilicon, thus allowing phosphorus to be used as the n-type dopant.

According to one embodiment, a semiconductor memory device includes first and second semiconductor layers and a first conductive layer. The first and second semiconductor layers extend in a first direction. The second semiconductor layer is stacked above the first semiconductor layer in a second direction intersecting the first direction. The first conductive layer intersects the first and second semiconductor layers and extends in the second direction. The first conductive layer includes first and second portions intersecting the first and second semiconductor layers respectively. A width of the first portion in the first direction is smaller than a width of the second portion in the first direction. A thickness of the first semiconductor layer in the second direction is larger than a thickness of the second semiconductor layer in the second direction.