Abstract: A method can include ion implanting with the gate mask to form first halo regions and ion implanting with the gate mask and first spacers as a mask to form second halo regions. The gate mask and first spacers can be removed, and an epitaxial layer formed. A dummy gate mask can be formed. Ion implanting with the dummy gate mask can from source-drain extensions. Second spacers can be formed on sides of the dummy gate mask. Ion implanting with the dummy gate mask and second spacers as a mask can form source and drain regions. A surface dielectric layer can be formed and planarized to expose a top of the dummy gate. The dummy gate can be removed to form gate openings between the second spacers. A hi-K dielectric layer and at least two gate metal layers within the gate opening. Related devices are also disclosed.

Abstract: A transistor structure can include a semiconductor-on-insulator substrate that includes an upper substrate region separated from a lower substrate region by a buried insulator. Shallow halo implant regions can be formed in an upper substrate region having a peak concentration at a first depth within the upper substrate region. Deep halo implant regions can be formed in the upper substrate region having a peak concentration at a second depth lower than the first depth. An epitaxial layer can be formed on top of the upper substrate region and below the control gate. Source and drain regions both of a second conductivity type formed in at least the epitaxial layer. In some embodiments, a lower substrate region can be biased for a double-gate effect.

Abstract: A transistor structure can include a semiconductor-on-insulator substrate that includes an upper substrate region separated from a lower substrate region by a buried insulator. Shallow halo implant regions can be formed in an upper substrate region having a peak concentration at a first depth within the upper substrate region. Deep halo implant regions can be formed in the upper substrate region having a peak concentration at a second depth lower than the first depth. An epitaxial layer can be formed on top of the upper substrate region and below the control gate. Source and drain regions both of a second conductivity type formed in at least the epitaxial layer. In some embodiments, a lower substrate region can be biased for a double-gate effect.

Abstract: A method of forming a transistor can include forming a gate mask on a substrate having a vertical location aligned with that of a transistor control gate; implanting first conductivity type dopants with the gate mask as an implant mask to form a first shallow halo region; implanting first conductivity type dopants with at least the gate mask as an implant mask to form a first deep halo region having a peak dopant concentration profile at a greater substrate depth than the first shallow halo region; forming an epitaxial layer on top of the substrate; forming a first control gate structure on the epitaxial layer; and forming a first source or drain region, of a second conductivity type, in at least the epitaxial layer to a side of the first control gate, and over the first shallow halo region and the first deep halo region.

Abstract: A method of forming a transistor can include forming a gate mask on a substrate having a vertical location aligned with that of a transistor control gate; implanting first conductivity type dopants with the gate mask as an implant mask to form a first shallow halo region; implanting first conductivity type dopants with at least the gate mask as an implant mask to form a first deep halo region having a peak dopant concentration profile at a greater substrate depth than the first shallow halo region; forming an epitaxial layer on top of the substrate; forming a first control gate structure on the epitaxial layer; and forming a first source or drain region, of a second conductivity type, in at least the epitaxial layer to a side of the first control gate, and over the first shallow halo region and the first deep halo region.

Abstract: A junction field effect transistor comprises a semiconductor substrate. A first impurity region of a first conductivity type is formed in the substrate. A second impurity region of the first conductivity type is formed in the substrate and spaced apart from the first impurity region. A channel region of the first conductivity type is formed between the first and second impurity regions. A gate region of a second conductivity type is formed in the substrate between the first and second impurity regions. A gap region is formed in the substrate between the gate region and the first impurity region such that the first impurity region is spaced apart from the gate region.

Abstract: Reduced leakage current field-effect transistors and fabrication methods. Semiconductor device including substrate of first conductivity type, first well and second well of second conductivity type in substrate, channel of second conductivity type between first well and second well in substrate, and gate region of first conductivity type within channel, wherein gate region is electrically operable to modulate depletion width of channel. First well may be a drain region and the second well may be a source region. Channel includes first link region between gate region and first well or drain region and second link region between the gate region and second well or source region; wherein first link region is of second conductivity type of at least two doping densities. First link region is higher doped in a portion adjacent to drain region than in another portion adjacent to gate region. Method of fabricating a reduced leakage current FET.

Abstract: A junction field effect transistor comprises a semiconductor substrate. A first impurity region of a first conductivity type is formed in the substrate. A second impurity region of the first conductivity type is formed in the substrate and spaced apart from the first impurity region. A channel region of the first conductivity type is formed between the first and second impurity regions. A gate region of a second conductivity type is formed in the substrate between the first and second impurity regions. A gap region is formed in the substrate between the gate region and the first impurity region such that the first impurity region is spaced apart from the gate region.

Abstract: A junction field effect transistor comprises a semiconductor substrate. A source region of a first conductivity type is formed in the substrate. A drain region of the first conductivity type is formed in the substrate. A channel region of the first conductivity type is formed in the substrate. A gate region of a second conductivity type is formed in the substrate between the source and drain regions. A first virtual link region is formed in the substrate between the gate region and either the source region or the drain region. A dielectric material overlays the first virtual link region. A first electrode region overlays the dielectric material.

Abstract: A junction field effect transistor comprises a semiconductor substrate. A source region of a first conductivity type is formed in the substrate. A drain region of the first conductivity type is formed in the substrate. A channel region of the first conductivity type is formed in the substrate. A gate region of a second conductivity type is formed in the substrate between the source and drain regions. A first virtual link region is formed in the substrate between the gate region and either the source region or the drain region. A dielectric material overlays the first virtual link region. A first electrode region overlays the dielectric material.

Abstract: A junction field effect transistor comprises a semiconductor substrate. A first impurity region of a first conductivity type is formed in the substrate. A second impurity region of the first conductivity type is formed in the substrate and spaced apart from the first impurity region. A channel region of the first conductivity type is formed between the first and second impurity regions. A gate region of a second conductivity type is formed in the substrate between the first and second impurity regions. A gap region is formed in the substrate between the gate region and the first impurity region such that the first impurity region is spaced apart from the gate region.

Abstract: A transistor structure having dimensions below about 100 nm is provided. The transistor structure comprises a substrate with a first polarity. The substrate includes a shallow halo implant having the first polarity defined at a first depth within the substrate. The substrate also has a deep halo implant which is the same polarity as the substrate and is defined to a second depth deeper than the first depth of the shallow halo implant. The shallow halo implant and the deep halo implant allow a peak concentration of substrate impurities at a level below the gate such that the resistance of the transistor is minimized along with the threshold voltage, short channel effects and leakage current in the transistor.