An object is to provide a semiconductor device with a novel structure in which stored data can be held even when power is not supplied and there is no limit on the number of write operations. The semiconductor device includes a first memory cell including a first transistor and a second transistor, a second memory cell including a third transistor and a fourth transistor, and a driver circuit. The first transistor and the second transistor overlap at least partly with each other. The third transistor and the fourth transistor overlap at least partly with each other. The second memory cell is provided over the first memory cell. The first transistor includes a first semiconductor material. The second transistor, the third transistor, and the fourth transistor include a second semiconductor material.

A semiconductor device capable of high speed operation is provided. Further, a semiconductor device in which change in electric characteristics due to a short channel effect is hardly caused is provided. An oxide semiconductor having crystallinity is used for a semiconductor layer of a transistor. A channel formation region, a source region, and a drain region are formed in the semiconductor layer. The source region and the drain region are formed by self-aligned process in which one or more elements selected from Group 15 elements are added to the semiconductor layer with the use of a gate electrode as a mask. The source region and the drain region can have a wurtzite crystal structure.

Some embodiments include apparatuses and methods having a conductive line, a memory cell string including memory cells located in different levels the apparatus, and a select circuit including a select transistor and a coupling component coupled between the conductive line and the memory cell string. Other embodiments including additional apparatuses and methods are described.

A semiconductor device includes a substrate having a memory array region and a peripheral region, isolation layers formed in the peripheral region to define an active region, offset insulating layers separated from each other and formed in the active region, and a gate electrode having edges overlapping with the offset insulating layers and arranged in the active region between the offset insulating layers.

A voltage switching apparatus includes a plurality of high voltage switching circuits operable in response to a single control signal, and suitable for pumping a voltage level of a switching signal to a target level based on the voltage level of the switching signal and a common control unit suitable for generating the single control signal.

A method of forming Si or Ge-based and III-V based vertically integrated nanowires on a single substrate and the resulting device are provided. Embodiments include forming first trenches in a Si, Ge, III-V, or Si.sub.xGe.sub.1-x substrate; forming a conformal SiN, SiO.sub.xC.sub.yN.sub.z layer over side and bottom surfaces of the first trenches; filling the first trenches with SiO.sub.x; forming a first mask over portions of the Si, Ge, III-V, or Si.sub.xGe.sub.1-x substrate; removing exposed portions of the Si, Ge, III-V, or Si.sub.xGe.sub.1-x substrate, forming second trenches; forming III-V, III-V.sub.xM.sub.y, or Si nanowires in the second trenches; removing the first mask and forming a second mask over the III-V.sub.xM.sub.y, or Si nanowires and intervening first trenches; removing the SiO.sub.x layer, forming third trenches; and removing the second mask.

A method of manufacturing a non-volatile memory is described. A substrate including a first region and a second region located at periphery of the first region is provided. A plurality of stacked structures are formed on the first region of the substrate. A wall structure is formed on the second region of the substrate. A conductive layer is formed over the substrate. A bottom anti-reflective coating is formed over the conductive layer. The bottom anti-reflective coating and the conductive layer are etched back. The conductive layer is patterned.

A semiconductor manufacturing method includes forming a first film on an upper surface of a substrate. The semiconductor manufacturing method includes forming concave portions extending from an upper surface of the first film to below the upper surface of the substrate. The method includes forming a second film from bottom surfaces of the concave portions to a first position in the concave portions between the upper surface of the first film and the upper surface of the substrate. The method includes forming a third film in the concave portions to cover side walls of the concave portions and an upper surface of the second film. The method includes grinding the third film to expose the second film. The method includes removing the second film. The method includes forming a fourth film from the bottom surfaces of the concave portions to at least a lower surface of the third film.

A ferroelectric memory device may include a semiconductor substrate, a plurality of ferroelectric layers, a source, a drain and a gate. The semiconductor substrate may have a recess. The ferroelectric layers may be formed in the recess. The source may be arranged at a first side of the recess. The drain may be arranged at a second side of the recess opposite to the first side. The gate may be arranged on the ferroelectric layers. The ferroelectric layers may be polarized by different electric fields.

A non-volatile memory device may include a semiconductor substrate, a ferroelectric layer, a source, a drain, a gate and a channel region. The semiconductor substrate may have a recess. The ferroelectric layer may be formed in the recess. The source may be arranged at a first side of the recess. The drain may be arranged at a second side of the recess opposite to the first side. The gate may be arranged on the ferroelectric layers. The channel region may be formed on the recess between the source and the drain.