Structures and formation methods of a semiconductor device structure are provided. The formation method includes forming a fin structure over a semiconductor substrate and forming a first isolation feature in the fin structure. The formation method also includes forming a second isolation feature over the semiconductor substrate after the formation of the first isolation feature. The fin structure and the first isolation feature protrude from the second isolation feature. The formation method further includes forming gate stacks over the second isolation feature, wherein the gate stacks surround the fin structure and the first isolation feature.

Structures and formation methods of a semiconductor device structure are provided. The formation method includes forming a fin structure over a semiconductor substrate and forming a first isolation feature in the fin structure. The formation method also includes forming a second isolation feature over the semiconductor substrate after the formation of the first isolation feature. The fin structure and the first isolation feature protrude from the second isolation feature. The formation method further includes forming gate stacks over the second isolation feature, wherein the gate stacks surround the fin structure and the first isolation feature.

The present disclosure provides a semiconductor structure and a manufacturing method thereof, and relates to the technical field of semiconductors. The semiconductor structure includes: a base, including a doped region; a recess, located in the doped region; and a gradient layer, filling the recess, wherein a doping concentration of the gradient layer varies gradually from a bottom of the recess upwards.

The present disclosure provides a semiconductor structure and a manufacturing method thereof, and relates to the technical field of semiconductors. The semiconductor structure includes: a base, including a doped region; a recess, located in the doped region; and a gradient layer, filling the recess, wherein a doping concentration of the gradient layer varies gradually from a bottom of the recess upwards.

A semiconductor device and a method of forming the same are provided. The semiconductor device includes a gate stack over an active region and a source/drain region in the active region adjacent the gate stack. The source/drain region includes a first semiconductor layer having a first germanium concentration and a second semiconductor layer over the first semiconductor layer. The second semiconductor layer has a second germanium concentration greater than the first germanium concentration. The source/drain region further includes a third semiconductor layer over the second semiconductor layer and a fourth semiconductor layer over the third semiconductor layer. The third semiconductor layer has a third germanium concentration greater than the second germanium concentration. The fourth semiconductor layer has a fourth germanium concentration less than the third germanium concentration.

Single gate and dual gate FinFET devices suitable for use in an SRAM memory array have respective fins, source regions, and drain regions that are formed from portions of a single, contiguous layer on the semiconductor substrate, so that STI is unnecessary. Pairs of FinFETs can be configured as dependent-gate devices wherein adjacent channels are controlled by a common gate, or as independent-gate devices wherein one channel is controlled by two gates. Metal interconnects coupling a plurality of the FinFET devices are made of a same material as the gate electrodes. Such structural and material commonalities help to reduce costs of manufacturing high-density memory arrays.

Single gate and dual gate FinFET devices suitable for use in an SRAM memory array have respective fins, source regions, and drain regions that are formed from portions of a single, contiguous layer on the semiconductor substrate, so that STI is unnecessary. Pairs of FinFETs can be configured as dependent-gate devices wherein adjacent channels are controlled by a common gate, or as independent-gate devices wherein one channel is controlled by two gates. Metal interconnects coupling a plurality of the FinFET devices are made of a same material as the gate electrodes. Such structural and material commonalities help to reduce costs of manufacturing high-density memory arrays.

A method for forming a semiconductor structure is provided. The method includes forming a fin structure over a substrate and forming an isolation structure over the substrate. In addition, the fin structure is protruded from the isolation structure. The method further includes trimming the fin structure to a first width and forming a Ge-containing material covering the fin structure. The method further includes annealing the fin structure and the Ge-containing material to form a modified fin structure. The method also includes trimming the modified fin structure to a second width.

A method for forming a semiconductor structure is provided. The method includes forming a fin structure over a substrate and forming an isolation structure over the substrate. In addition, the fin structure is protruded from the isolation structure. The method further includes trimming the fin structure to a first width and forming a Ge-containing material covering the fin structure. The method further includes annealing the fin structure and the Ge-containing material to form a modified fin structure. The method also includes trimming the modified fin structure to a second width.

A first gate and a second gate are formed on a substrate with a gap between the first and second gates. The first gate has a first sidewall. The second gate has a second sidewall directly facing the first sidewall. A first sidewall spacer is disposed on the first sidewall. A second sidewall spacer is disposed on the second sidewall. A contact etch stop layer is deposited on the first and second gates and on the first and second sidewall spacers. The contact etch stop layer is subjected to a tilt-angle plasma etching process to trim a corner portion of the contact etch stop layer. An inter-layer dielectric layer is then deposited on the contact etch stop layer and into the gap.