Abstract:
Methods and structures for forming short-channel finFETs with vertical and abrupt source and drain junctions are described. During fabrication, source and drain regions of the finFET may be recessed vertically and laterally under gate spacers. A buffer having a high dopant density may be formed on vertical sidewalls of the channel region after recessing the fin. Raised source and drain structures may be formed at the recessed source and drain regions. The raised source and drain structures may impart strain to the channel region.
Abstract:
Structures including a vertical-transport field-effect transistor and a planar field-effect transistor, and methods of forming such structures. First and second sacrificial fins are respectively formed over first and second areas of the first device region. One or more semiconductor fins of the vertical-transport field-effect transistor are formed over the second device region. A first gate electrode of the planar field-effect transistor, which is arranged on the first device region between the first sacrificial fin and the second sacrificial fin, and a second gate electrode of the vertical-transport field-effect transistor, which is wrapped about the one or more semiconductor fins, are currently formed.
Abstract:
A method for making a semiconductor device may include forming first and second semiconductor regions laterally adjacent one another and each comprising a first semiconductor material. The method may further include forming an in-situ doped, punch-through stopper layer above the second semiconductor region comprising the first semiconductor material and a first dopant, and forming a semiconductor buffer layer above the punch-through stopper layer, where the punch-through stopper layer includes the first semiconductor material. The method may also include forming a third semiconductor region above the semiconductor buffer layer, where the third semiconductor region includes a second semiconductor material different than the first semiconductor material. In addition, at least one first fin may be formed from the first semiconductor region, and at least one second fin may be formed from the second semiconductor region, the punch-through stopper layer, the semiconductor buffer layer, and the third semiconductor region.
Abstract:
Structures for a nanosheet field-effect transistor and methods for forming a structure for a nanosheet field-effect transistor. A fin is formed that includes a first nanosheet channel layer and a second nanosheet channel layer arranged in a vertical stack. A cavity is formed between a portion of the first nanosheet channel layer and a portion of the second nanosheet channel layer. An epitaxially-grown source/drain region is connected with the portion of the first nanosheet channel layer and the portion of the second nanosheet channel layer. A gate structure is formed that includes a section located in a space between the first nanosheet channel layer and the second nanosheet channel layer. The cavity is surrounded by the first nanosheet channel layer, the second nanosheet channel layer, the section of the gate structure, and the source/drain region to define an air gap spacer.
Abstract:
Device structures and fabrication methods for a vertical field-effect transistor. A semiconductor fin is formed that projects from a first source/drain region. A first spacer layer is formed on the first source/drain region. A dielectric layer is formed that extends in the vertical direction from the first spacer layer to a top surface of the semiconductor fin. The dielectric layer is recessed in the vertical direction, and a second spacer layer is formed on the recessed dielectric layer such that the dielectric layer is located in the vertical direction between the first spacer layer and the second spacer layer. After the dielectric layer is removed to open a space between the first spacer layer and the second spacer layer, a gate electrode is formed in the space. The vertical field-effect transistor has a gate length that is equal to a thickness of the recessed dielectric layer.
Abstract:
Structures for spacers of a field-effect transistor and methods for forming such spacers. A mask layer has a feature separated from a vertical sidewall of a first gate structure by a space of predetermined width that exposes a top surface of a semiconductor body. A spacer is formed adjacent to the vertical sidewall of the first gate structure. The spacer has a first section in the space and a second section. The first section of the spacer is located vertically between the second section of the spacer and the top surface of the semiconductor body. The first section of the spacer extends through the space to the top surface of the semiconductor body, and the first section of the spacer fully fills the space.
Abstract:
A semiconductor device comprises an insulation layer, an active semiconductor layer formed on an upper surface of the insulation layer, and a plurality of fins formed on the insulation layer. The fins are formed in the gate and spacer regions between a first source/drain region and second source/drain region, without extending into the first and second source/drain regions.
Abstract:
A method of fabricating features of a vertical transistor include performing a first etch process to form a first portion of a fin in a substrate; depositing a spacer material on sidewalls of the first portion of the fin; performing a second etch process using the spacer material as a pattern to elongate the fin and form a second portion of the fin in the substrate, the second portion having a width that is greater than the first portion; oxidizing a region of the second portion of the fin beneath the spacer material to form an oxidized channel region; and removing the oxidized channel region to form a vacuum channel.
Abstract:
Techniques and structures for controlling etch-back of a finFET fin are described. One or more layers may be deposited over the fin and etched. Etch-back of a planarization layer may be used to determine a self-limited etch height of one or more layers adjacent the fin and a self-limited etch height of the fin. Strain-inducing material may be formed at regions of the etched fin to induce strain in the channel of a finFET.
Abstract:
A semiconductor device which includes: a substrate; a first set of fins above the substrate of a first semiconductor material; a second set of fins above the substrate and of a second semiconductor material different than the first semiconductor material; and an isolation region positioned between the first and second sets of fins, the isolation region having a nitride layer. The isolation region may be an isolation pillar or an isolation trench.