Abstract:
III-N semiconductor heterostructures on III-N epitaxial islands laterally overgrown from a mesa of a silicon substrate. An IC may include a III-N semiconductor device disposed on the III-N epitaxial island overhanging the silicon mesa and may further include a silicon-based MOSFET monolithically integrated with the III-N device. Lateral epitaxial overgrowth from silicon mesas may provide III-N semiconductor regions of good crystal quality upon which transistors or other active semiconductor devices may be fabricated. Overhanging surfaces of III-N islands may provide multiple device layers on surfaces of differing polarity. Spacing between separate III-N islands may provide mechanical compliance to an IC including III-N semiconductor devices. Undercut of the silicon mesa may be utilized for transfer of III-N epitaxial islands to alternative substrates.
Abstract:
A group III-N nanowire is disposed on a substrate. A longitudinal length of the nanowire is defined into a channel region of a first group III-N material, a source region electrically coupled with a first end of the channel region, and a drain region electrically coupled with a second end of the channel region. A second group III-N material on the first group III-N material serves as a charge inducing layer, and/or barrier layer on surfaces of nanowire. A gate insulator and/or gate conductor coaxially wraps completely around the nanowire within the channel region. Drain and source contacts may similarly coaxially wrap completely around the drain and source regions.
Abstract:
A subfin layer is deposited on a substrate. A fin layer is deposited on the subfin layer. The subfin layer has a conduction band energy offset relative to the fin layer to prevent a leakage in the subfin layer. In one embodiment, the subfin layer comprises a group IV semiconductor material layer that has a bandgap greater than a bandgap of the fin layer.
Abstract:
III-N semiconductor heterostructures on III-N epitaxial islands laterally overgrown from a mesa of a silicon substrate. An IC may include a III-N semiconductor device disposed on the III-N epitaxial island overhanging the silicon mesa and may further include a silicon-based MOSFET monolithically integrated with the III-N device. Lateral epitaxial overgrowth from silicon mesas may provide III-N semiconductor regions of good crystal quality upon which transistors or other active semiconductor devices may be fabricated. Overhanging surfaces of III-N islands may provide multiple device layers on surfaces of differing polarity. Spacing between separate III-N islands may provide mechanical compliance to an IC including III-N semiconductor devices. Undercut of the silicon mesa may be utilized for transfer of III-N epitaxial islands to alternative substrates.
Abstract:
Trenches (and processes for forming the trenches) are provided that reduce or prevent crystaline defects in selective epitaxial growth of type III-V or Germanium (Ge) material (e.g., a “buffer” material) from a top surface of a substrate material. The defects may result from collision of selective epitaxial sidewall growth with oxide trench sidewalls. Such trenches include (1) a trench having sloped sidewalls at an angle of between 40 degrees and 70 degrees (e.g., such as 55 degrees) with respect to a substrate surface; and/or (2) a combined trench having an upper trench over and surrounding the opening of a lower trench (e.g., the lower trench may have the sloped sidewalls, short vertical walls, or tall vertical walls). These trenches reduce or prevent defects in the epitaxial sidewall growth where the growth touches or grows against vertical sidewalls of a trench it is grown in.
Abstract:
Architectures and techniques for co-integration of heterogeneous materials, such as group III-V semiconductor materials and group IV semiconductors (e.g., Ge) on a same substrate (e.g. silicon). In embodiments, multi-layer heterogeneous semiconductor material stacks having alternating nanowire and sacrificial layers are employed to release nanowires and permit formation of a coaxial gate structure that completely surrounds a channel region of the nanowire transistor. In embodiments, individual PMOS and NMOS channel semiconductor materials are co-integrated with a starting substrate having a blanket layers of alternating Ge/III-V layers. In embodiments, vertical integration of a plurality of stacked nanowires within an individual PMOS and individual NMOS device enable significant drive current for a given layout area.
Abstract:
A single fin or a pair of co-integrated n- and p-type single crystal electronic device fins are epitaxially grown from a substrate surface at a bottom of one or a pair of trenches formed between shallow trench isolation (STI) regions. The fin or fins are patterned and the STI regions are etched to form a height of the fin or fins extending above etched top surfaces of the STI regions. The fin heights may be at least 1.5 times their width. The exposed sidewall surfaces and a top surface of each fin is epitaxially clad with one or more conformal epitaxial materials to form device layers on the fin. Prior to growing the fins, a blanket buffer epitaxial material may be grown from the substrate surface; and the fins grown in STI trenches formed above the blanket layer. Such formation of fins reduces defects from material interface lattice mismatches.
Abstract:
Transistors for high voltage and high frequency operation. A non-planar, polar crystalline semiconductor body having a top surface disposed between first and second opposite sidewalls includes a channel region with a first crystalline semiconductor layer disposed over the first and second sidewalls. The first crystalline semiconductor layer is to provide a two dimensional electron gas (2DEG) within the channel region. A gate structure is disposed over the first crystalline semiconductor layer along at least the second sidewall to modulate the 2DEG. First and second sidewalls of the non-planar polar crystalline semiconductor body may have differing polarity, with the channel proximate to a first of the sidewalls. The gate structure may be along a second of the sidewalls to gate a back barrier. The polar crystalline semiconductor body may be a group III-nitride formed on a silicon substrate with the (1010) plane on a (110) plane of the silicon.
Abstract:
Trenches (and processes for forming the trenches) are provided that reduce or prevent crystaline defects in selective epitaxial growth of type III-V or Germanium (Ge) material (e.g., a “buffer” material) from a top surface of a substrate material. The defects may result from collision of selective epitaxial sidewall growth with oxide trench sidewalls. Such trenches include (I) a trench having sloped sidewalls at an angle of between 40 degrees and 70 degrees (e.g., such as 55 degrees) with respect to a substrate surface; and/or (2) a combined trench having an upper trench over and surrounding the opening of a lower trench (e.g., the lower trench may have the sloped sidewalls, short vertical walls, or tall vertical walls). These trenches reduce or prevent defects in the epitaxial sidewall growth where the growth touches or grows against vertical sidewalls of a trench it is grown in.
Abstract:
Methods of forming III-V LED structures on silicon fin templates are described. Those methods and structures may include forming an n-doped III-V layer on a silicon (111) plane of a silicon fin, forming a quantum well layer on the n-doped III-V layer, forming a p-doped III-V layer on the quantum well layer, and then forming an ohmic contact layer on the p-doped III-V layer.