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 variety of applications can include memory devices designed to provide enhanced gate-induced-drain-leakage (GIDL) current during memory erase operations. The enhanced operation can be provided by enhancing the electric field in the channel structures of select gate transistors to strings of memory cells. The channel structures can be implemented as a segmented portion for drains and a portion opposite a gate. The segmented portion includes one or more fins and one or more non-conductive regions with both fins and non-conductive regions extending vertically from the portion opposite the gate. Variations of a border region for the portion opposite the gate with the segmented portion can include fanged regions extending from the fins into the portion opposite the gate or rounded border regions below the non-conductive regions. Such select gate transistors can be formed using a single photo mask process. Additional devices, systems, and methods are discussed.

A semiconductor device is provided that includes a local passthrough interconnect structure present in a non-active device region of the device. A dielectric fill material structure is located between the local passthrough interconnect structure and a functional gate structure that is present in an active device region that is laterally adjacent to the non-active device region. The semiconductor device has reduced capacitance (and thus circuit speed is not compromised) as compared to an equivalent device in which a metal-containing sacrificial gate structure is used instead of the dielectric fill material structure.

A method of controlling gate formation of a semiconductor device includes acquiring a correlation between gate critical dimensions (CDs) and etching recipes for forming gate trenches; measuring a gate CD on a target wafer; determining an etching recipe based on the correction and the measured gate CD; and performing an etching process on the target wafer to form a gate trench with the determined etching recipe.

A finFET device and methods of forming a finFET device are provided. The device includes a fin and a capping layer over the fin. The device also includes a gate stack over the fin, the gate stack including a gate electrode and a gate dielectric. The gate dielectric extends along sidewalls of the capping layer. The device further includes a gate spacer adjacent to sidewalls of the gate electrode, the capping layer being interposed between the gate spacer and the fin.

Devices and structures that include a gate spacer having a gap or void are described along with methods of forming such devices and structures. In accordance with some embodiments, a structure includes a substrate, a gate stack over the substrate, a contact over the substrate, and a spacer disposed laterally between the gate stack and the contact. The spacer includes a first dielectric sidewall portion and a second dielectric sidewall portion. A void is disposed between the first dielectric sidewall portion and the second dielectric sidewall portion.

A gate-all-around nanowire device and a method for forming the gate-all-around nanowire device. A first fin and a dielectric layer on the first fin are formed on a substrate. The first fin includes the at least one first epitaxial layer and the at least one second epitaxial layer that are alternately stacked. The dielectric layer exposes a channel region of the first fin. A doping concentration at a lateral surface of the channel region and a doping concentration at a central region of the channel region are different from each other in the at least one second epitaxial layer. After the at least one first epitaxial layer is removed from the channel region, the at least one second epitaxial layer in the channel region serves as at least one nanowire. A gate surrounding the at least one nanowire is formed.

In some embodiments, a field effect transistor (FET) structure comprises a body structure, dielectric structures, a gate structure and a source or drain region. The gate structure is formed over the body structure. The source or drain region is embedded in the body structure beside the gate structure, and abuts and is extended beyond the dielectric structure. The source or drain region contains stressor material with a lattice constant different from that of the body structure. The source or drain region comprises a first region formed above a first level at a top of the dielectric structures and a second region that comprises downward tapered side walls formed under the first level and abutting the corresponding dielectric structures.

A semiconductor device includes a substrate; a fin structure formed on a substrate; and a gate feature formed over the fin structure, the gate feature comprising a gate dielectric layer, wherein the gate dielectric layer traverses the fin structure to overlay a central portion of the fin structure and opposite side portions of the fin structure that are located in respective undercuts formed in respective portions of a dielectric layer located adjacent to opposite sidewalls of the gate feature, wherein the undercuts extend beyond respective sidewalls of the gate feature and away from the central portion of the fin structure.

Multi-gate devices and methods for fabricating such are disclosed herein. An exemplary method includes forming a gate dielectric layer around first channel layers in a p-type gate region and around second channel layers in an n-type gate region. Sacrificial features are formed between the second channel layers in the n-type gate region. A p-type work function layer is formed over the gate dielectric layer in the p-type gate region and the n-type gate region. After removing the p-type work function layer from the n-type gate region, the sacrificial features are removed from between the second channel layers in the n-type gate region. An n-type work function layer is formed over the gate dielectric layer in the n-type gate region. A metal fill layer is formed over the p-type work function layer in the p-type gate region and the n-type work function layer in the n-type gate region.