The present disclosure relates to an integrated circuit (IC) in which a memory structure comprises a ferroelectric structure without critical-thickness limitations. The memory structure comprises a first electrode and the ferroelectric structure. The ferroelectric structure is vertically stacked with the first electrode and comprises a first ferroelectric layer, a second ferroelectric layer, and a first restoration layer. The second ferroelectric layer overlies the first ferroelectric layer, and the first restoration layer is between and borders the first and second ferroelectric layers. The first restoration layer is a different material type than that of the first and second ferroelectric layers and is configured to decouple crystalline lattices of the first and second ferroelectric layers so the first and second ferroelectric layers do not reach critical thicknesses. A critical thickness corresponds to a thickness at and above which the orthorhombic phase becomes thermodynamically unstable, such that remanent polarization is lost.

A method for fabricating a semiconductor device includes the steps of forming a gate structure on a substrate, forming an interlayer dielectric (ILD) layer on the gate structure, forming a contact hole in the ILD layer adjacent to the gate structure, performing a plasma doping process to form a doped layer in the ILD layer and a source/drain region adjacent to the gate structure, forming a conductive layer in the contact hole, planarizing the conductive layer to form a contact plug, removing the doped layer to form an air gap adjacent to the contact plug, and then forming a stop layer on the ILD layer and the contact plug.

A semiconductor device includes a drain, a source, a gate electrode, and a nanowire between the source and drain. The nanowire has a first section with a first thickness and a second section with a second thickness greater than the first thickness. The second section is between the first section and at least one of the source or drain. The first nanowire includes a channel when a voltage is applied to the gate electrode.

A method includes forming a dummy gate stack, etching the dummy gate stack to form an opening, depositing a first dielectric layer extending into the opening, and depositing a second dielectric layer on the first dielectric layer and extending into the opening. A planarization process is then performed to form a gate isolation region including the first dielectric layer and the second dielectric layer. The dummy gate stack is then removed to form trenches on opposing sides of the gate isolation region. The method further includes performing a first etching process to remove sidewall portions of the first dielectric layer, performing a second etching process to thin the second dielectric layer, and forming replacement gates in the trenches.

A high voltage semiconductor device includes a semiconductor substrate, an isolation structure, a gate oxide layer, and a gate structure. The semiconductor substrate includes a channel region, and at least a part of the isolation structure is disposed in the semiconductor substrate and surrounds the channel region. The gate oxide layer is disposed on the semiconductor substrate, and the gate oxide layer includes a first portion and a second portion. The second portion is disposed at two opposite sides of the first portion in a horizontal direction, and a thickness of the first portion is greater than a thickness of the second portion. The gate structure is disposed on the gate oxide layer and the isolation structure.

The present disclosure provides embodiments of semiconductor structures and method of forming the same. An example semiconductor structure includes a first source/drain feature and a second source/drain feature and a hybrid fin disposed between the first source/drain feature and the second source/drain feature and extending lengthwise along a first direction. The hybrid fin includes an inner feature and an outer layer disposed around the inner feature. The outer layer includes silicon oxycarbonitride and the inner feature includes silicon carbonitride.

The present invention relates to an LDMOS device and a method of forming the device, in which a barrier layer includes n etch stop layers. Insulating layers are formed between adjacent etch stop layers. Since an interlayer dielectric layer and the insulating layers are both oxides that differ from the material of the etch stop layers, etching processes can be stopped at the n etch stop layers when they are proceeding in the oxides, thus forming n field plate holes terminating at the respective n etch stop layers. A lower end of the first field plate hole proximal to a gate structure is closest to a drift region, and a lower end of the n-th field plate hole proximal to a drain region is farthest from the drift region. With this arrangement, more uniform electric field strength can be obtained around front and rear ends of the drift region, resulting in an effectively improved electric field distribution throughout the drift region and thus in an increased breakdown voltage.

A device includes a substrate, a first stack of semiconductor nanostructures vertically overlying the substrate, and a gate structure surrounding the semiconductor nanostructures and abutting an upper side and first and second lateral sides of the first stack. A first epitaxial region laterally abuts a third lateral side of the first stack, and a second epitaxial region laterally abuts a fourth lateral side of the first stack. A first inactive fin laterally abuts the first epitaxial region, and a second inactive fin laterally abuts the second epitaxial region and is physically separated from the first inactive fin by the gate structure.

A semiconductor device includes a first transistor and a second transistor. The first transistor includes: a first source and a first drain separated by a first distance, a first semiconductor structure disposed between the first source and first drain, a first gate electrode disposed over the first semiconductor structure, and a first dielectric structure disposed over the first gate electrode. The first dielectric structure has a lower portion and an upper portion disposed over the lower portion and wider than the lower portion. The second transistor includes: a second source and a second drain separated by a second distance greater than the first distance, a second semiconductor structure disposed between the second source and second drain, a second gate electrode disposed over the second semiconductor structure, and a second dielectric structure disposed over the second gate electrode. The second dielectric structure and the first dielectric structure have different material compositions.

A method for forming a high electron mobility transistor is disclosed. A mesa structure having a channel layer and a barrier layer is formed on a substrate. The mesa structure has two first edges extending along a first direction and two second edges extending along a second direction. A passivation layer is formed on the substrate and the mesa structure. A first opening and a plurality of second openings connected to a bottom surface of the first opening are formed and through the passivation layer, the barrier layer and a portion of the channel layer. In a top view, the first opening exposes the two first edges of the mesa structure without exposing the two second edges of the mesa structure. A metal layer is formed in the first opening and the second openings thereby forming a contact structure.