A semiconductor memory device includes a substrate; a control gate disposed on the substrate; a source diffusion region disposed in the substrate and on a first side of the control gate; a select gate disposed on the source diffusion region, wherein the select gate has a recessed top surface; a charge storage structure disposed under the control gate; a first spacer disposed between the select gate and the control gate and between the charge storage structure and the select gate; a wordline gate disposed on a second side of the control gate opposite to the select gate; a second spacer between the wordline gate and the control gate; and a drain diffusion region disposed in the substrate and adjacent to the wordline gate.

A semiconductor memory device includes a semiconductor substrate, a select gate on the semiconductor substrate, a control gate disposed adjacent to the select gate and having a first sidewall and a second sidewall, and a charge storage layer between the control gate and the semiconductor substrate. The control gate includes a third sidewall close to the second sidewall of the select gate, a fourth sidewall opposite to the third sidewall, and a non-planar top surface between the third sidewall and the fourth sidewall. The non-planar top surface includes a first surface region that descends from the third sidewall to the fourth sidewall. The charge storage layer extends to the second sidewall of the select gate.

A semiconductor memory device comprises: a plurality of first conductive layers arranged separated from each other in a first direction; a plurality of second conductive layers arranged, electrically insulated from the plurality of first conductive layers, at a different position in a second direction intersecting the first direction with respect to the first conductive layers; a plurality of memory structures; and a source structure. Respective one ends of the plurality of memory structures and one end of the source structure are electrically connected. The respective other ends of the plurality of memory structures are respectively electrically connected to different first wirings of a plurality of first wirings formed in the same layer in the first direction. The other end of the source structure is electrically connected to a second wiring formed in a different layer from the plurality of first wirings in the first direction.

An improvement is achieved in the reliability of a semiconductor device. In a memory cell region, a plurality of fins are provided which are portions of a semiconductor substrate extending in an x-direction along a main surface of the semiconductor substrate and spaced apart from each other in a y-direction orthogonal to the x-direction along the main surface of the semiconductor substrate. Between the fins adjacent to each other in the y-direction, a portion of an upper surface of an isolation region is at a position higher than a surface obtained by connecting a position of the upper surface of the isolation region which is in contact with a side wall of one of the fins to a position of the upper surface of the isolation region which is in contact with a side wall of the other fin. In a cross section along the y-direction, the upper surface of the isolation region has a projecting shape.

Various embodiments of the present application are directed towards a method to integrate NVM devices with a logic or BCD device. In some embodiments, an isolation structure is formed in a semiconductor substrate. The isolation structure demarcates a memory region of the semiconductor substrate, and further demarcates a peripheral region of the semiconductor substrate. The peripheral region may, for example, correspond to BCD device or a logic device. A doped well is formed in the peripheral region. A dielectric seal layer is formed covering the memory and peripheral regions, and further covering the doped well. The dielectric seal layer is removed from the memory region, but not the peripheral region. A memory cell structure is formed on the memory region using a thermal oxidation process. The dielectric seal layer is removed from the peripheral region, and a peripheral device structure including a gate electrode is formed on the peripheral region.

A semiconductor device includes a semiconductor layer including a first main surface, a first region of a first conduction type that is formed at a surface layer portion of the first main surface, a second region of a first conduction type that is formed at the surface layer portion of the first main surface and is separated from the first region in a first direction, a channel region of a second conduction type that is formed between the first region and the second region in the surface layer portion of the first main surface, a first gate electrode that is formed in a vicinity of the first region in the first main surface, faces the channel region, and includes a first side portion and a second side portion on an opposite side of the first side portion in the first direction.

A trench is formed by removing a portion of each of the charge accumulation film and the insulating film located between the control gate electrode and the memory gate electrode. The insulating film is formed in the trench so that the upper surface of each of the insulating film and the charge accumulation film is covered with the insulating film. When exposing the upper surface of the control gate electrode and the memory gate electrode, the upper surface of each of the insulating film and the charge accumulation film is not exposed.

A semiconductor storage device includes first and second stacked bodies, a first semiconductor layer, a first charge storage layer, a conductive layer, and a first silicon oxide layer. The first stacked body includes first insulation layers and first gate electrode layers that are alternately stacked in a first direction. The first semiconductor layer extends in the first stacked body in the first direction. The first charge storage layer is provided between the first semiconductor layer and the first gate electrode layers. The conductive layer is provided between the first stacked body and the second stacked body and extends in the first direction and a second direction. The first silicon oxide layer is provided between the conductive layer and the first gate electrode layers. The first silicon oxide layer containing an impurity being at least one of phosphorus, boron, carbon, and fluorine.

A method used in forming a memory array comprising strings of memory cells comprises forming a stack comprising vertically-alternating first tiers and second tiers comprising laterally-spaced memory-block regions having horizontally-elongated trenches there-between. Two of the first tiers have different vertical thicknesses relative one another. Channel-material strings of memory cells extend through the first tiers and the second tiers. Through the horizontally-elongated trenches, first conductive material is formed in void space in the two first tiers. The first conductive material fills the first tier of the two first tiers that has a smaller of the different vertical thicknesses in individual of the memory-block regions. The first conductive material less-than-fills the first tier of the two first tiers that has a larger of the different vertical thicknesses in the individual memory-block regions. Through the horizontally-elongated trenches, the first conductive material is isotropically etched from the first tier having the larger vertical thickness in the individual memory-block regions to leave the first conductive material in the first tier having the smaller vertical thickness in the individual memory-block regions. After the isotropically etching of the first conductive material and through the horizontally-elongated trenches, second conductive material is formed in the first tier having the larger vertical thickness in the individual memory-block regions. Other embodiments, including structure independent of method, are disclosed.

A manufacturing method of a semiconductor device includes: (a) forming a gate structure for a control gate electrode on a semiconductor substrate; (b) forming a charge storage film so as to cover a first side surface, a second side surface, and an upper surface of the gate structure; (c) forming a conductive film for a memory gate electrode on the charge storage film; (d) removing a part of the charge storage film and a part of the conductive film such that the charge storage film and the conductive film remain in this order on the first side surface and the second side surface of the gate structure, thereby forming the memory gate electrode; and (e) removing apart of the gate structure separate from the first side surface and the second side surface such that a part of the semiconductor substrate is exposed from the gate structure.