We demonstrate undoped-body, gate-all-around (GAA) Si nanowire (NW) MOSFETs with excellent electrostatic scaling. These NW devices, with a TaN/Hf-based gate stack, have high drive-current performance with NFET/PFET I DSAT = 825/950 µA/µm (circumference-normalized) or 2592/2985 µA/µm (diameter-normalized) at supply voltage V DD = 1 V and off-current I OFF = 15 nA/µm. Superior NW uniformity is obtained through the use of a combined hydrogen annealing and oxidation process. Clear scaling of short-channel effects versus NW size is observed.

High performance and highly uniform gate-all-around silicon nanowire MOSFETs with wire size dependent scaling

A method for manufacturing a field effect transistor, includes: forming a mask of an insulating film on a semiconductor layer containing Si formed on a semiconductor substrate; forming the semiconductor layer into a mesa structure by performing etching with the use of the mask, the mesa structure extending in a direction parallel to an upper face of the semiconductor substrate; narrowing a distance between two sidewalls of the mesa structure and flattening the sidewalls by performing a heat treatment in a hydrogen atmosphere, the two sidewalls extending in the direction and facing each other; forming a gate insulating film covering the mesa structure having the sidewalls flattened; forming a gate electrode covering the gate insulating film; and forming source and drain regions at portions of the mesa structure, the portions being located on two sides of the gate electrode.

Field Effect Transistor and Method for Manufacturing the Same

Semiconductor-based electronic devices and techniques for fabrication thereof are provided. In one aspect, a device is provided comprising a first pad; a second pad and a plurality of nanowires connecting the first pad and the second pad in a ladder-like configuration formed in a silicon-on-insulator (SOI) layer over a buried oxide (BOX) layer, the nanowires having one or more dimensions defined by a re-distribution of silicon from the nanowires to the pads. The device can comprise a field-effect transistor (FET) having a gate surrounding the nanowires wherein portions of the nanowires surrounded by the gate form channels of the FET, the first pad and portions of the nanowires extending out from the gate adjacent to the first pad form a source region of the FET and the second pad and portions of the nanowires extending out from the gate adjacent to the second pad form a drain region of the FET.

Maskless process for suspending and thinning nanowires

We describe the fabrication of vertically stacked Silicon Nanowire Field Effect Transistors (SiNW FETs) in Gate-All Around (GAA) configuration. Stacks with the number of channels ranging from 1 to 12 have been successfully produced by means of a micrometer scale lithography and conventional fabrication techniques. It is shown that demonstrator Schottky Barrier (SB) devices fabricated with Cr/NiCr contacts present good subthreshold slope (70mV/dec), I ON /I OFF ratio ≥ 104 and reproducible ambipolar behavior.

/pdf/fabrication-and-characterization-of-vertically-stacked-gate-5g7ig5kon4.pdf

Fabrication and characterization of vertically stacked Gate-All-Around Si Nanowire FET arrays

Among other things, one or semiconductor arrangements, and techniques for forming such semiconductor arrangements are provided. For example, one or more silicon and silicon germanium stacks are utilized to form PMOS transistors comprising germanium nanowire channels and NMOS transistors comprising silicon nanowire channels. In an example, a first silicon and silicon germanium stack is oxidized to transform silicon to silicon oxide regions, which are removed to form germanium nanowire channels for PMOS transistors. In another example, silicon and germanium layers within a second silicon and silicon germanium stack are removed to form silicon nanowire channels for NMOS transistors. PMOS transistors having germanium nanowire channels and NMOS transistors having silicon nanowire channels are formed as part of a single fabrication process.

Silicon and silicon germanium nanowire formation

Three- and four-level matrices of 15 times 70 nm Si Nano-Beams have been integrated with a novel CMOS gate-all-around process (GAA) down to 80 nm gate length. Thanks to this 3D-GAA extension of a Finfet process, a more than 5times higher current density per layout surface is achieved compared to planar transistors with the same gate stack (HfO 2/TiN/Poly-Si). For the first time, several properties of this novel 3D architecture are explored: (i) HfO2/TiN gate stack is integrated, (ii) electrons and holes mobilities are measured on 150 beams matrices (3 levels) and compared to those of planar transistors (hi) a sub-100nm channel width is demonstrated and (iv) specific 3D integration challenges like zipping between nano-beams are discussed

Novel 3D integration process for highly scalable Nano-Beam stacked-channels GAA (NBG) FinFETs with HfO2/TiN gate stack

Four level matrices of round, 35nm in diameter Si nanowires (NWs) are obtained thanks to a top-down approach. In particular, we report optimized H2 annealing conditions (800to900°C) in order to reconstruct the plasma-etched surfaces of the suspended nanowires. The nanowire shape evolution has been studied in scanning electron microscopy, transmission electron microscopy, and atomic force microscopy. The side roughness decrease and the rounding of the NWs have been quantified. The instability of the anchors of the NWs to the contact regions has been evidenced and confirmed by surface diffusion simulations.

C. Isheden

Papers

Novel 3D integration process for highly scalable Nano-Beam stacked-channels GAA (NBG) FinFETs with HfO2/TiN gate stack

Hydrogen annealing of arrays of planar and vertically stacked Si nanowires