A method of forming a NAND flash memory includes anisotropically etching trenches of a gate stack down to an intermediate level in a floating gate polysilicon layer, leaving remaining portions of the floating gate polysilicon over the gate dielectric layer. Subsequently, forming a protective layer along exposed sides of the trenches. Then, electrically separating individual floating gates by a selective process that is directed to the remaining portions of the floating gate polysilicon layer exposed by trenches.

A gas sensor includes a field effect transistor supported on an oxide layer of a substrate, the field effect transistor having a doped source (p.sup.+ doped for T-FET and n+ doped for FET) and an n+ doped drain separated by an channel region (intrinsic for T-FET or slightly p-doped for FET), and a floating gate separated from the channel region by a gate oxide, a passivation layer covering the floating gate, and a sensing layer supported by the passivation layer, the sensing layer comprising nanofibers.

A nonvolatile memory device includes an active region extending in a first direction, a first single-layered gate intersecting the active region and extending in a second direction, a second single-layered gate intersecting the, active region and extending in the second direction, and a selection gate intersecting, the active region. The selection gate includes a first selection gate main line and a second selection gate main line that intersect the active region to be parallel with the first and second single-layered gates, a selection gate interconnection line that connects a first end of the first selection gate main line to a first end of the second selection gate main line and a selection gate extension that extends from a portion of the selection gate interconnection line to be disposed between first ends of the first and second single-layered gates,

Some embodiments include integrated circuits having first and second transistors. The first transistor is wider than the second transistor. The first and second transistors have first and second active regions, respectively. Dielectric features are associated with the first active region and break up the first active region. The second active region is not broken up to the same extent as the first active region. Some embodiments include methods of forming transistors. Active areas of first and second transistors are formed. The active area of the first transistor is wider than the active area of the second transistor. Dielectric features are formed in the active area of the first transistor. The active area of the first transistor is broken up to a different extent than the active area of the second transistor. The active areas of the first and second transistors are simultaneously doped.

A method comprises forming a memory gate structure adjacent to a control gate structure over a substrate, wherein a charge storage layer is between the memory gate structure and the control gate structure and a top surface of the memory gate structure is covered by a gate mask layer, forming a first spacer along sidewalls of the memory gate structure and the gate mask layer, wherein a sidewall of the memory gate structure is fully covered by the first spacer, applying an etching process to the charge storage layer to form an L-shaped charge storage layer and forming a first drain/source region adjacent to the memory gate structure and a second drain/source region adjacent to the control gate structure.

According to one embodiment, the stacked body includes a plurality of electrode films stacked with an insulating body. The insulating body includes a first insulating film provided between the electrode films in a region surrounding the columnar portions. A gap is provided between the electrode films in a region on a lateral side in the first direction of the interconnect portion.

According to one embodiment, a semiconductor device includes a semiconductor layer; an electrode layer; a first insulating film; a charge storage film; and a second insulating film. The first insulating film is provided between the electrode layer and the semiconductor layer. The charge storage film is provided between the first insulating film and the electrode layer. The charge storage film includes a charge trapping layer and a floating electrode layer. The floating electrode layer includes doped silicon. The second insulating film is provided between the floating electrode layer and the electrode layer.

A nonvolatile semiconductor memory device includes a charge storage layer on a first insulating film, a second insulating film which is provided on the charge storage layer, formed of layers, and a control gate electrode on the second insulating film. The second insulating film includes a bottom layer (A) provided just above the charge storage layer, a top layer (C) provided just below the control gate electrode, and a middle layer (B) provided between the bottom layer (A) and the top layer (C). The middle layer (B) has higher barrier height and lower dielectric constant than both the bottom layer (A) and the top layer (C). The average coordination number of the middle layer (B) is smaller than both the average coordination number of the top layer (C) and the average coordination number of the bottom layer (A).

A semiconductor device fabrication method includes forming a tunnel insulating film on a substrate containing silicon, forming a floating gate on the tunnel insulating film, forming an integral insulating film on the floating gate, and forming a control gate on the integral insulating film. The floating gate is formed on the tunnel insulating film by forming a seed layer containing amorphous silicon on the tunnel insulating film, forming an impurity later containing adsorbed boron or germanium on the seed layer, and forming a cap layer containing silicon on the impurity layer.

A semiconductor device includes a first conductor, a second conductor, a first insulator, a second insulator, a third insulator, a semiconductor, and an electron trap layer. The semiconductor includes a channel formation region. The electron trap layer overlaps with the channel formation region with the second insulator interposed therebetween. The first conductor overlaps with the channel formation region with the first insulator interposed therebetween. The second conductor overlaps with the electron trap layer with the third insulator interposed therebetween. The second conductor does not overlap with the channel formation region.