A method includes alternately stacking first semiconductor layers and second semiconductor layers over a substrate, patterning the first and second semiconductor layers into a fin structure, forming a dummy gate structure across the fin structure, depositing gate spacers over sidewalls of the dummy gate structure, removing the dummy gate structure to form a recess, removing the first semiconductor layers, depositing an interfacial layer wrapping the second semiconductor layers, depositing a high-k dielectric layer over the interfacial layer and over the sidewalls of the gate spacers, depositing a first gate electrode over the high-k dielectric layer, recessing the first gate electrode and the high-k dielectric layer to expose a top portion of the sidewalls of the gate spacers, depositing a low-k dielectric layer over the recessed high-k dielectric layer, and depositing a second gate electrode over the first gate electrode.

A semiconductor device includes an insulating substrate, a silicon layer on the insulating substrate, a dopant layer on the silicon layer, a buried spacer on a side surface of the dopant layer, a channel pattern on the dopant layer, the channel pattern comprising a plurality of semiconductor patterns vertically stacked and spaced apart from each other, a source/drain pattern on the buried spacer, the source/drain pattern connected to the channel pattern, a gate electrode on the channel pattern, the gate electrode comprising a plurality of inner electrodes between the semiconductor patterns, respectively, a lower power interconnection line in a lower portion of the insulating substrate, and a backside contact extending into the insulating substrate and the silicon layer to electrically connect the lower power interconnection line to the source/drain pattern. A side surface of the backside contact is in contact with the silicon layer and the buried spacer.

A transistor and a manufacturing method. The transistor includes a semiconductor base substrate, an active structure, a dielectric structure, and a gate stack structure. The active structure is formed on the semiconductor base substrate. The active structure includes a source region, a drain region, and a channel region located between the source region and the drain region. The channel region includes at least two nanostructures stacked in a thickness direction of the semiconductor base substrate. In the channel region, a bottom nanostructure has a greater width than other nanostructures. The dielectric structure is formed between the semiconductor base substrate and the active structure. The dielectric structure is in contact with the bottom nanostructure. The gate stack structure is formed on a surface of the bottom nanostructure not in contact with the dielectric structure, and the gate stack surrounds a periphery of the other nanostructures.

Methods for forming packaged semiconductor devices including backside power rails and packaged semiconductor devices formed by the same are disclosed. In an embodiment, a device includes a first integrated circuit device including a first transistor structure in a first device layer; a front-side interconnect structure on a front-side of the first device layer; and a backside interconnect structure on a backside of the first device layer, the backside interconnect structure including a first dielectric layer on the backside of the first device layer; and a first contact extending through the first dielectric layer to a source/drain region of the first transistor structure; and a second integrated circuit device including a second transistor structure in a second device layer; and a first interconnect structure on the second device layer, the first interconnect structure being bonded to the front-side interconnect structure by dielectric-to-dielectric and metal-to-metal bonds.

A method for manufacturing a gate-all-around TFET device. The method comprises: forming, on a substrate, a channel stack comprising channel layer(s) and sacrificial layer(s) that alternate with each other; forming, on the substrate, a dummy gate astride the channel stack; forming a first spacer at a surface of the dummy gate; etching the sacrificial layer(s) to form recesses on side surfaces of the channel stack; forming second spacers in the recesses, respectively; fabricating a source and a drain separately, where a region for fabricating the source is shielded by a dielectric material when fabricating the drain, and a region for fabricating the drain is shielded by another dielectric material when fabricating the source; etching the dummy gate and the sacrificial layer(s) to form a space for a surrounding gate; and fabricating a surrounding dielectric-metal gate in the space.

Semiconductor device and the manufacturing method thereof are disclosed. An exemplary method comprises forming a first stack structure and a second stack structure in a first area over a substrate, wherein each of the stack structures includes semiconductor layers separated and stacked up; depositing a first interfacial layer around each of the semiconductor layers of the stack structures; depositing a gate dielectric layer around the first interfacial layer; forming a dipole oxide layer around the gate dielectric layer; removing the dipole oxide layer around the gate dielectric layer of the second stack structure; performing an annealing process to form a dipole gate dielectric layer for the first stack structure and a non-dipole gate dielectric layer for the second stack structure; and depositing a first gate electrode around the dipole gate dielectric layer of the first stack structure and the non-dipole gate dielectric layer of the second stack structure.

An optoelectronic synaptic memristor includes: a bottom electrode layer, a porous structure layer modified with quantum dots, a two-dimensional material layer, a transparent top electrode layer, and a waveguide layer, which are arranged in sequence from top to bottom, wherein the waveguide is ridge shaped for light conduction, comprising a wedge-shaped output terminal, wherein: through the wedge-shaped output terminal of the waveguide, light is vertically injected into the two-dimensional material layer and the porous structure layer modified with the quantum dots. By integrating the waveguide and the optoelectronic memristor, the present invention obtains the highly controlled characteristics with high alignment and confinement for light effect on the device and has advantages in realizing optoelectronic synergy in the optoelectronic synaptic memristors. The present invention has strong controllability and excellent performance and can be widely used in high-density integration of storage and computing, artificial synapses, artificial intelligence, etc.

The present disclosure describes a semiconductor device and methods for forming the same. The semiconductor device includes nanostructures on a substrate and a source/drain region in contact with the nanostructures. The source/drain region includes epitaxial end caps, where each epitaxial end cap is formed at an end portion of a nanostructure of the nanostructures. The source/drain region also includes an epitaxial body in contact with the epitaxial end caps and an epitaxial top cap formed on the epitaxial body. The semiconductor device further includes gate structure formed on the nanostructures.

A semiconductor structure includes a stack of semiconductor layers disposed over a substrate, a metal gate structure disposed over and interleaved with the stack of semiconductor layers, the metal gate structure including a gate electrode disposed over a gate dielectric layer, a first isolation structure disposed adjacent to a first sidewall of the stack of semiconductor layers, where the gate dielectric layer fills space between the first isolation structure and the first sidewall of the stack of semiconductor layers, and a second isolation structure disposed adjacent to a second sidewall of the stack of semiconductor layers, where the gate electrode fills the space between the second isolation structure and the second sidewall of the stack of semiconductor layers.

A device includes a bottom transistor, a top transistor, and an epitaxial isolation structure. The bottom transistor includes a first channel layer, first source/drain epitaxial structures, and a first gate structure. The first source/drain epitaxial structures are on opposite sides of the first channel layer. The first gate structure is around the first channel layer. The top transistor is over the bottom transistor and includes a second channel layer, second source/drain epitaxial structures, and a second gate structure. The second source/drain epitaxial structures are on opposite sides of the second channel layer. The second gate structure is around the second channel layer. The epitaxial isolation structure is between and in contact with one of the first source/drain epitaxial structures and one of the second source/drain epitaxial structures, such that the one of the first source/drain epitaxial structures is electrically isolated from the one of the second source/drain epitaxial structures.