Abstract: Techniques related to forming low defect density III-N films, device structures, and systems incorporating such films are discussed. Such techniques include epitaxially growing a first crystalline III-N structure within an opening of a first dielectric layer and extending onto the first dielectric layer, forming a second dielectric layer over the first dielectric layer and laterally adjacent to a portion of the first structure, and epitaxially growing a second crystalline III-N structure extending laterally onto a region of the second dielectric layer.

Abstract: Gallium nitride transistors having multiple threshold voltages are described. In an example, a transistor includes a gallium nitride layer over a substrate, a gate stack over the gallium nitride layer, a source region on a first side of the gate stack, and a drain region on a second side of the gate stack, the second side opposite the first side, wherein the gate stack has a gate length in a first direction extending from the source region to the drain region, the gate stack having a gate width in a second direction perpendicular to the first direction and parallel to the source region and the drain region. The transistor also includes a polarization layer beneath the gate stack and on the GaN layer, the polarization layer having a first portion having a first thickness under a first gate portion and a second thickness under a second gate portion.

Abstract: Disclosed herein are IC structures, packages, and devices that include III-N transistors integrated on the same substrate or die as resonators of RF filters. An example IC structure includes a support structure (e.g., a substrate), a resonator, provided over a first portion of the support structure, and an III-N transistor, provided over a second portion of the support structure. The IC structure includes a piezoelectric material so that first and second electrodes of the resonator enclose a first portion of the piezoelectric material, while a second portion of the piezoelectric material is enclosed between the channel material of the III-N transistor and the support structure. In this manner, one or more resonators of an RF filter may be monolithically integrated with one or more III-N transistors. Such integration may reduce costs and improve performance by reducing RF losses incurred when power is routed off chip.

Abstract: A transistor comprises a base layer that includes a channel region, wherein the base layer and the channel region include group III-V semiconductor material. A gate stack is above the channel region, the gate stack comprises a gate electrode and a composite gate dielectric stack, wherein the composite gate dielectric stack comprises a first large bandgap oxide layer, a low bandgap oxide layer, and a second large bandgap oxide layer to provide a programmable voltage threshold. Source and drain regions are adjacent to the channel region.

Abstract: Techniques are disclosed herein for ferroelectric-based field-effect transistors (FETs) with threshold voltage (VT) switching for enhanced RF switch transistor on-state and off-state performance. Employing a ferroelectric gate dielectric layer that can switch between two ferroelectric states enables a higher VT during the transistor off-state (VT,hi) and a lower VT during the transistor on-state (VT,lo). Accordingly, the transistor on-state resistance (Ron) can be maintained low due to the available relatively high gate overdrive (Vg,on?VT,lo) while still handling a relatively high maximum RF power in the transistor off-state due to the high VT,hi ?Vg,off value. Thus, the Ron of an RF switch transistor can be improved without sacrificing maximum RF power, and/or vice versa, the maximum RF power can be improved without sacrificing the Ron. A ferroelectric layer (e.g., including HfxZryO) can be formed between a transistor gate dielectric layer and gate electrode to achieve such benefits.

Abstract: A variable capacitance III-N device having multiple two-dimensional electron gas (2DEG) layers are described. In some embodiments, the device comprises a first source and a first drain; a first polarization layer adjacent to the first source and the first drain; a first channel layer coupled to the first source and the first drain and adjacent to the first polarization layer, the first channel layer comprising a first 2DEG region; a second source and a second drain; a second polarization layer adjacent to the second source and the second drain; and a second channel layer coupled to the second source and the second drain and adjacent to the second polarization layer, the second channel layer comprising a second 2DEG region, wherein the second channel layer is over the first polarization layer.

Abstract: IC structures that include transmission line structures to be integrated with III-N devices are disclosed. An example transmission line structure includes a transmission line of an electrically conductive material provided above a stack of a III-N semiconductor material and a polarization material. The transmission line structure further includes means for reducing electromagnetic coupling between the line and charge carriers present below the interface of the polarization material and the III-N semiconductor material. In some embodiments, said means include a shield material of a metal or a doped semiconductor provided over portions of the polarization material that are under the transmission line. In other embodiments, said means include dopant atoms implanted into the portions of the polarization material that are under the transmission line, and into at least an upper portion of the III-N semiconductor material under such portions of the polarization material.

Abstract: A transistor includes a polarization layer above a channel layer including a first III-Nitride (III-N) material, a gate electrode above the polarization layer, a source structure and a drain structure on opposite sides of the gate electrode, where the source structure and a drain structure each include a second III-N material. The transistor further includes a silicide on at least a portion of the source structure or the drain structure. A contact is coupled through the silicide to the source or drain structure.

Abstract: Group III-N transistors of complementary conductivity type employing two polarization junctions of complementary type. Each III-N polarization junction may include two III-N material layers having opposite crystal polarities. The opposing polarities may induce a two-dimensional charge sheet within each of the two III-N material layers. Opposing crystal polarities may be induced through introduction of an intervening layer between two III-N material layers. A III-N heterostructure may include two III-N polarization junctions. A 2D electron gas (2DEG) is induced at a first polarization junction and a 2D hole gas (2DHG) is induced at the second polarization junction. Transistors of complementary type may utilize a separate one of the polarization junctions, enabling III-N transistors to implement CMOS circuitry.

Abstract: A structure, comprising an island comprising a III-N material. The island extends over a substrate and has a sloped sidewall. A cap comprising a III-N material extends laterally from a top surface and overhangs the sidewall of the island. A device, such as a transistor, light emitting diode, or resonator, may be formed within, or over, the cap.

Abstract: A device includes a first Group III-Nitride (III-N) material, a gate electrode above the III-N material, and the gate electrode. The device further includes a tiered field plate, suitable for increasing gate breakdown voltage with minimal parasitics. In the tiered structure, a first plate is on the gate electrode, the first plate having a second sidewall laterally beyond a sidewall of the gate, and above the III-N material by a first distance. A second plate on the first plate has a third sidewall laterally beyond the second sidewall and above the III-N material by a second distance, greater than the first. A source structure and a drain structure are on opposite sides of the gate electrode, where the source and drain structures each include a second III-N material.

Abstract: Gate-all-around integrated circuit structures having depopulated channel structures, and methods of fabricating gate-all-around integrated circuit structures having depopulated channel structures using a selective bottom-up approach, are described. For example, an integrated circuit structure includes a vertical arrangement of nanowires above a substrate. The vertical arrangement of nanowires has one or more active nanowires above one or more oxide nanowires. A first gate stack is over and around the one or more active nanowires. A second gate stack is over and around the one or more oxide nanowires.

Abstract: A method for forming non-planar capacitors of desired dimensions is disclosed. The method is based on providing a three-dimensional structure of a first material over a substrate, enclosing the structure with a second material that is sufficiently etch-selective with respect to the first material, and then performing a wet etch to remove most of the first material but not the second material, thus forming a cavity within the second material. Shape and dimensions of the cavity are comparable to those desired for the final non-planar capacitor. At least one electrode of a capacitor may then be formed within the cavity. Using the etch selectivity of the first and second materials advantageously allows applying wet etch techniques for forming high aspect ratio openings in fabricating non-planar capacitors, which is easier and more reliable than relying on dry etch techniques.

Abstract: A semiconductor device is disclosed. The semiconductor device includes a substrate, an epitaxial layer above the substrate, a Schottky barrier material on the epitaxial layer, a Schottky metal contact extending into the Schottky barrier material, a fin structure that extends in a first direction, a first angled implant in a first side of the fin structure that has an orientation that is orthogonal to the first direction, and a second angled implant in a second side of the fin structure that has an orientation that is orthogonal to the first direction. The second side is opposite to the first side. A first cathode region and a second cathode region are coupled by parts of the first angled implant and the second angled implant that extend in the first direction.

Abstract: A transistor includes a polarization layer above a channel layer including a first III-Nitride (III-N) material, a gate electrode above the polarization layer, a source structure and a drain structure on opposite sides of the gate electrode, where the source structure and a drain structure each include a second III-N material. The transistor further includes a silicide on at least a portion of the source structure or the drain structure. A contact is coupled through the silicide to the source or drain structure.

Abstract: Transistor structures including a fin structure having multiple graded III-N material layers with polarization layers therebetween, integrated circuits including such transistor structures, and methods for forming the transistor structures are discussed. The transistor structures further include a source, a drain, and a gate coupled to the fin structure. The fin structure provides a multi-gate multi-nanowire confined transistor architecture.

Abstract: Group-III nitride (III-N) tunnel devices with a device structure including multiple quantum wells. A bias voltage applied across first device terminals may align the band structure to permit carrier tunneling between a first carrier gas residing in a first of the wells to a second carrier gas residing in a second of the wells. A III-N tunnel device may be operable as a diode, or further include a gate electrode. The III-N tunnel device may display a non-linear current-voltage response with negative differential resistance, and be employed as a frequency mixer operable in the GHz and THz bands. In some examples, a GHz-THz input RF signal and local oscillator signal are coupled into a gate electrode of a III-N tunnel device biased within a non-linear regime to generate an output RF signal indicative of a frequency difference between the RF signal and a local oscillator signal.

Abstract: Integrated circuit architectures for load and input matching that include a capacitance selectable between a plurality of discrete levels, which are associated with a number of field effect transistors (FET) capacitor structures that are in an on-state. The capacitance comprises a metal-oxide-semiconductor (MOS) capacitance associated with each of the FET capacitor structures, and may be selectable through application of a bias voltage applied between a first circuit node and a second circuit node. Gate electrodes of the FET capacitor structures may be coupled in electrical parallel to the first circuit node, while source/drains of the FET capacitor structures are coupled in electrical parallel to the second circuit node. Where the FET capacitor structures have different gate-source threshold voltages, the number of FET capacitor structures in the on-state may be varied according to the bias voltage, and the capacitance correspondingly tuned to a desired value.

Abstract: A variable capacitance III-N device having multiple two-dimensional electron gas (2DEG) layers are described. In some embodiments, the device comprises a first source and a first drain; a first polarization layer adjacent to the first source and the first drain; a first channel layer coupled to the first source and the first drain and adjacent to the first polarization layer, the first channel layer comprising a first 2DEG region; a second source and a second drain; a second polarization layer adjacent to the second source and the second drain; and a second channel layer coupled to the second source and the second drain and adjacent to the second polarization layer, the second channel layer comprising a second 2DEG region, wherein the second channel layer is over the first polarization layer.

Abstract: A Group III-Nitride (III-N) device structure is presented comprising: a heterostructure having three or more layers comprising III-N material, a cathode comprising donor dopants, wherein the cathode is on a first layer of the heterostructure, an anode within a recess that extends through two or more of the layers of the heterostructure, wherein the anode comprises a first region wherein the anode is separated from the heterostructure by a high k dielectric material, and a second region wherein the anode is in direct contact with the heterostructure, and a conducting region in the first layer in direct contact to the cathode and conductively connected to the anode. Other embodiments are also disclosed and claimed.