Abstract:
A strip of sacrificial semiconductor material is formed on top of a non-sacrificial semiconductor material substrate layer. A conformal layer of the non-sacrificial semiconductor material is epitaxially grown to cover the substrate layer and the strip of sacrificial semiconductor material. An etch is performed to selectively remove the strip of sacrificial semiconductor material and leave a hollow channel surrounded by the conformal layer and the substrate layer. Using an anneal, the conformal layer and the substrate layer are reflowed to produce an optical waveguide structure including the hollow channel.
Abstract:
A method for manufacturing a hybrid SOI/bulk substrate, including the steps of starting from an SOI wafer comprising a single-crystal semiconductor layer called SOI layer, on an insulating layer, on a single-crystal semiconductor substrate; depositing on the SOI layer at least one masking layer and forming openings crossing the masking layer, the SOI layer, and the insulating layer, to reach the substrate; growing by a repeated alternation of selective epitaxy and partial etching steps a semiconductor material; and etching insulating trenches surrounding said openings filled with semiconductor material, while encroaching inwards over the periphery of the openings.
Abstract:
Methods for semiconductor fabrication include forming a well in a semiconductor substrate. A pocket is formed within the well, the pocket having an opposite doping polarity as the well to provide a p-n junction between the well and the pocket. Defects are created at the p-n junction such that a leakage resistance of the p-n junction is decreased.
Abstract:
A memory device may include a semiconductor substrate, and a memory transistor in the semiconductor substrate. The memory transistor may include source and drain regions in the semiconductor substrate and a channel region therebetween, and a gate stack having a first dielectric layer over the channel region, a second dielectric layer over the first dielectric layer, a first diffusion barrier layer over the second dielectric layer, a first electrically conductive layer over the first diffusion barrier layer, a second diffusion barrier layer over the first electrically conductive layer, and a second electrically conductive layer over the second diffusion barrier layer. The first and second dielectric layers may include different dielectric materials, and the first diffusion barrier layer may be thinner than the second diffusion barrier layer.
Abstract:
A method for manufacturing a hybrid SOI/bulk substrate, including the steps of starting from an SOI wafer comprising a single-crystal semiconductor layer called SOI layer, on an insulating layer, on a single-crystal semiconductor substrate; depositing on the SOI layer at least one masking layer and forming openings crossing the masking layer, the SOI layer, and the insulating layer, to reach the substrate; growing by a repeated alternation of selective epitaxy and partial etching steps a semiconductor material; and etching insulating trenches surrounding said openings filled with semiconductor material, while encroaching inwards over the periphery of the openings.
Abstract:
Isolation trenches are etched through an active silicon layer overlying a buried oxide on a substrate into the substrate, and through any pad dielectric(s) on the active silicon layer. Lateral epitaxial growth of the active silicon layer forms protrusions into the isolation trenches to a lateral distance of at least about 5 nanometers, and portions of the isolation trenches around the protrusions are filled with dielectric. Raised source/drain regions are formed on portions of the active silicon layer including a dielectric. As a result, misaligned contacts passing around edges of the raised source/drain regions remain spaced apart from sidewalls of the substrate in the isolation trenches.
Abstract:
A multi-fin FINFET device may include a substrate and a plurality of semiconductor fins extending upwardly from the substrate and being spaced apart along the substrate. Each semiconductor fin may have opposing first and second ends and a medial portion therebetween, and outermost fins of the plurality of semiconductor fins may comprise an epitaxial growth barrier on outside surfaces thereof. The FINFET may further include at least one gate overlying the medial portions of the semiconductor fins, a plurality of raised epitaxial semiconductor source regions between the semiconductor fins adjacent the first ends thereof, and a plurality of raised epitaxial semiconductor drain regions between the semiconductor fins adjacent the second ends thereof.
Abstract:
A tunneling transistor is implemented in silicon, using a FinFET device architecture. The tunneling FinFET has a non-planar, vertical, structure that extends out from the surface of a doped drain formed in a silicon substrate. The vertical structure includes a lightly doped fin defined by a subtractive etch process, and a heavily-doped source formed on top of the fin by epitaxial growth. The drain and channel have similar polarity, which is opposite that of the source. A gate abuts the channel region, capacitively controlling current flow through the channel from opposite sides. Source, drain, and gate terminals are all electrically accessible via front side contacts formed after completion of the device. Fabrication of the tunneling FinFET is compatible with conventional CMOS manufacturing processes, including replacement metal gate and self-aligned contact processes. Low-power operation allows the tunneling FinFET to provide a high current density compared with conventional planar devices.
Abstract:
A tensile strained silicon layer is patterned to form a first group of fins in a first substrate area and a second group of fins in a second substrate area. The second group of fins is covered with a tensile strained material, and an anneal is performed to relax the tensile strained silicon semiconductor material in the second group of fins and produce relaxed silicon semiconductor fins in the second area. The first group of fins is covered with a mask, and silicon-germanium material is provided on the relaxed silicon semiconductor fins. Germanium from the silicon germanium material is then driven into the relaxed silicon semiconductor fins to produce compressive strained silicon-germanium semiconductor fins in the second substrate area (from which p-channel finFET devices are formed). The mask is removed to reveal tensile strained silicon semiconductor fins in the first substrate area (from which n-channel finFET devices are formed).
Abstract:
A method of making a structurally stable SiGe-on-insulator FinFET employs a silicon nitride liner to prevent de-stabilizing oxidation at the base of a SiGe fin. The silicon nitride liner blocks access of oxygen to the lower corners of the fin to facilitate fabrication of a high-concentration SiGe fin. The silicon nitride liner is effective as an oxide barrier even if its thickness is less than about 5 nm. Use of the SiN liner provides structural stability for fins that have higher germanium content, in the range of 25-55% germanium concentration.