Abstract: Methods to achieve strained channel finFET devices and resulting finFET devices are presented. In an embodiment, a method for processing a field effect transistor (FET) device may include forming a fin structure comprising a fin channel on a substrate. The method may also include forming a sacrificial epitaxial layer on a side of the fin structure. Additionally, the method may include forming a deep recess in a region that includes at least a portion of the fin structure, wherein the fin structure and sacrificial layer relax to form a strain on the fin channel. The method may also include depositing source/drain (SD) material in the deep recess to preserve the strain on the fin channel.

Abstract: A field effect transistor (FET) structure includes: a gate; a first spacer having a first dielectric constant at a first region adjacent to the gate; and a second spacer having a second dielectric constant that is greater than the first dielectric constant at a second region adjacent to the gate.

Abstract: A semiconductor device and a method to form the semiconductor device are disclosed. An n-channel component of the semiconductor device includes a first horizontal nanosheet (hNS) stack and a p-channel component includes a second hNS stack. The first hNS stack includes a first gate structure having a plurality of first gate layers and at least one first channel layer. A first internal spacer is disposed between at least one first gate layer and a first source/drain structure in which the first internal spacer has a first length. The second hNS stack includes a second gate structure having a plurality of second gate layers and at least one second channel layer. A second internal spacer is disposed between at least one second gate layer and a second source/drain structure in which the second internal spacer has a second length that is greater than the first length.

Abstract: A method to form a nanosheet stack for a semiconductor device includes forming a stack of a plurality of sacrificial layers and at least one channel layer on an underlayer in which a sacrificial layer is in contact with the underlayer, each channel layer being in contact with at least one sacrificial layer, the sacrificial layers are formed from SiGe and the at least one channel layer is formed from Si; forming at least one source/drain trench region in the stack to expose surfaces of the SiGe sacrificial layers and a surface of the at least one Si channel layer; and oxidizing the exposed surfaces of the SiGe sacrificial layers and the exposed surface of the at least one Si layer in an environment of wet oxygen, or ozone and UV.

Abstract: A method for fabricating a fin field effect transistor (finFET) device with a strained channel. During fabrication, after the fin is formed, a sacrificial epitaxial gate stressor is deposited on the fin, causing strain in the fin. SD structures are then formed to anchor the ends of the fin, and the sacrificial epitaxial gate stressor is removed.

Abstract: A method for fabricating a fin field effect transistor (finFET) device with a strained channel. During fabrication, after the fin is formed, a sacrificial epitaxial gate stressor is deposited on the fin, causing strain in the fin. SD structures are then formed to anchor the ends of the fin, and the sacrificial epitaxial gate stressor is removed.

Abstract: A method to form a nanosheet stack for a semiconductor device includes forming a stack of a plurality of sacrificial layers and at least one channel layer on an underlayer in which a sacrificial layer is in contact with the underlayer, each channel layer being in contact with at least one sacrificial layer, the sacrificial layers are formed from SiGe and the at least one channel layer is formed from Si; forming at least one source/drain trench region in the stack to expose surfaces of the SiGe sacrificial layers and a surface of the at least one Si channel layer; and oxidizing the exposed surfaces of the SiGe sacrificial layers and the exposed surface of the at least one Si layer in an environment of wet oxygen, or ozone and UV.

Abstract: A method of forming a horizontal nanosheet device or a horizontal nanowire device includes forming a dummy gate and a series of external spacers on a stack including an alternating arrangement of sacrificial layers and channel layers, deep etching portions of the stack between the external spacers to form electrode recesses for a source electrode and a drain electrode, performing an etch-back on portions of the sacrificial layers to form internal spacer recesses above and below each of the channel layers, forming doped internal spacers in the internal spacer recesses, and forming doped extension regions of the source electrode and the drain electrode by outdiffusion of dopants from the doped internal spacers. The method may also include epitaxially regrowing the source electrode and the drain electrode in the electrode recesses.

Abstract: A method of forming a horizontal nanosheet device or a horizontal nanowire device includes forming a dummy gate and a series of external spacers on a stack including an alternating arrangement of sacrificial layers and channel layers, deep etching portions of the stack between the external spacers to form electrode recesses for a source electrode and a drain electrode, performing an etch-back on portions of the sacrificial layers to form internal spacer recesses above and below each of the channel layers, forming doped internal spacers in the internal spacer recesses, and forming doped extension regions of the source electrode and the drain electrode by outdiffusion of dopants from the doped internal spacers. The method may also include epitaxially regrowing the source electrode and the drain electrode in the electrode recesses.

Abstract: A semiconductor device and a method to form the semiconductor device are disclosed. An n-channel component of the semiconductor device includes a first horizontal nanosheet (hNS) stack and a p-channel component includes a second hNS stack. The first hNS stack includes a first gate structure having a plurality of first gate layers and at least one first channel layer. A first internal spacer is disposed between at least one first gate layer and a first source/drain structure in which the first internal spacer has a first length. The second hNS stack includes a second gate structure having a plurality of second gate layers and at least one second channel layer. A second internal spacer is disposed between at least one second gate layer and a second source/drain structure in which the second internal spacer has a second length that is greater than the first length.

Abstract: Methods to achieve strained channel finFET devices and resulting finFET devices are presented. In an embodiment, a method for processing a field effect transistor (FET) device may include forming a fin structure comprising a fin channel on a substrate. The method may also include forming a sacrificial epitaxial layer on a side of the fin structure. Additionally, the method may include forming a deep recess in a region that includes at least a portion of the fin structure, wherein the fin structure and sacrificial layer relax to form a strain on the fin channel. The method may also include depositing source/drain (SD) material in the deep recess to preserve the strain on the fin channel.

Abstract: A field effect transistor (FET) includes a nanosheet stack having first and second stacked semiconductor channel layers. The first channel layer defines a channel region of a tunnel FET, and the second channel layer defines a channel region of a thermionic FET. Source and drain regions are provided on opposite sides of the nanosheet stack such that the first and second channel layers extend therebetween. A first portion of the source region adjacent the first channel layer and a second portion of the source region adjacent the second channel layer have opposite semiconductor conductivity types. Related fabrication and operating methods are also discussed.

Abstract: A field effect transistor (FET) structure includes: a gate; a first spacer having a first dielectric constant at a first region adjacent to the gate; and a second spacer having a second dielectric constant that is greater than the first dielectric constant at a second region adjacent to the gate.

Abstract: Integrated circuit devices including contacts and methods of forming the same are provided. The devices may include a fin on a substrate, a gate structure on the fin and a source/drain region in the fin at a side of the gate structure. The devices may further include a contact plug covering an uppermost surface of the source/drain region and a sidewall of the gate structure. The contact plug may include an inner portion including a first material and an outer portion including a second material different from the first material. The outer portion may at least partially cover a sidewall of the inner portion, and a portion of the outer portion may be disposed between the sidewall of the gate structure and the sidewall of the inner portion.

Abstract: An integrated circuit chip includes a semiconductor substrate, a first back-end-of-line unit circuit that includes a first group of field effect transistors, a second gate-loaded unit circuit that includes a second group of field effect transistors. The first group of field effect transistors includes a first transistor and the second group of field effect transistors includes a second transistor. A bottom surface of a gate electrode of the first transistor extends closer to a bottom surface of the semiconductor substrate than does a bottom surface of a gate electrode of the second transistor.

Abstract: An integrated circuit may include multiple first, non-Si, nanosheet field-effect transistors (FETs) and multiple second, Si, nanosheet FETs. Nanosheets of ones of the first, non-Si, nanosheet FETs may include less than about 30% Si. The first, non-Si, nanosheet FETs may define a critical speed path of the circuit of the integrated circuit. Nanosheets of ones of the second, Si, nanosheet FETs may include more than about 30% Si. The second, Si, nanosheet FETs may define a non-critical speed path of the integrated circuit. Ones of the first, non-Si, nanosheet FETs may be configured to have a higher speed than a speed of ones of the second, Si, nanosheet FETs.

Abstract: A field effect transistor (FET) includes a nanosheet stack having first and second stacked semiconductor channel layers. The first channel layer defines a channel region of a tunnel FET, and the second channel layer defines a channel region of a thermionic FET. Source and drain regions are provided on opposite sides of the nanosheet stack such that the first and second channel layers extend therebetween. A first portion of the source region adjacent the first channel layer and a second portion of the source region adjacent the second channel layer have opposite semiconductor conductivity types. Related fabrication and operating methods are also discussed.

Abstract: An integrated circuit may include multiple first, non-Si, nanosheet field-effect transistors (FETs) and multiple second, Si, nanosheet FETs. Nanosheets of ones of the first, non-Si, nanosheet FETs may include less than about 30% Si. The first, non-Si, nanosheet FETs may define a critical speed path of the circuit of the integrated circuit. Nanosheets of ones of the second, Si, nanosheet FETs may include more than about 30% Si. The second, Si, nanosheet FETs may define a non-critical speed path of the integrated circuit. Ones of the first, non-Si, nanosheet FETs may be configured to have a higher speed than a speed of ones of the second, Si, nanosheet FETs.

Abstract: An integrated circuit chip includes a semiconductor substrate, a first back-end-of-line unit circuit that includes a first group of field effect transistors, a second gate-loaded unit circuit that includes a second group of field effect transistors. The first group of field effect transistors includes a first transistor and the second group of field effect transistors includes a second transistor. A bottom surface of a gate electrode of the first transistor extends closer to a bottom surface of the semiconductor substrate than does a bottom surface of a gate electrode of the second transistor.

Abstract: Integrated circuit devices including contacts and methods of forming the same are provided. The devices may include a fin on a substrate, a gate structure on the fin and a source/drain region in the fin at a side of the gate structure. The devices may further include a contact plug covering an uppermost surface of the source/drain region and a sidewall of the gate structure. The contact plug may include an inner portion including a first material and an outer portion including a second material different from the first material. The outer portion may at least partially cover a sidewall of the inner portion, and a portion of the outer portion may be disposed between the sidewall of the gate structure and the sidewall of the inner portion.