Abstract: Embodiments of the present disclosure describe apparatuses, methods, and systems of an integrated circuit (IC) device. The IC device may include a buffer layer disposed on a substrate, the buffer layer including gallium (Ga) and nitrogen (N), a barrier layer disposed on the buffer layer, the barrier layer including aluminum (Al) and nitrogen (N), wherein the barrier layer includes an oxidized portion of the barrier layer, a gate dielectric disposed on the oxidized portion of the barrier layer, and a gate electrode disposed on the gate dielectric, wherein the oxidized portion of the barrier layer is disposed in a gate region between the gate electrode and the buffer layer.

Abstract: A photodetector includes a high-indium-concentration (H-I-C) absorption layer having a Group III sublattice indium concentration greater than 53%. The H-I-C absorption layer improves responsivity without decreasing bandwidth. The photoconversion structure that includes the H-I-C absorption layer can be formed on any type of substrate through the use of a metamorphic buffer layer to provide a lattice constant gradient between the photoconversion structure and the substrate. The responsivity of the photodetector can be further improved by passing an incoming optical signal through the H-I-C absorption layer at least twice.

Abstract: A pitch averaging Bragg grating includes a plurality of grating peaks spaced by different pitch values. By selecting the different pitch values to have an average pitch value equal to a target pitch value, the pitch averaging Bragg grating can be made to perform like a constant pitch Bragg grating having a fixed pitch at the target pitch value. The different pitch values can be multiples of the minimum placement resolution of a production tool to be used to produce the Bragg grating. The pitch averaging Bragg grating can be used in place of constant pitch Bragg gratings in optical devices and systems, such as DFB lasers, DBR lasers, optical spectral filters, multi-wavelength laser arrays, and WDM systems.

Abstract: A pitch averaging Bragg grating includes a plurality of grating peaks spaced by different pitch values. By selecting the different pitch values to have an average pitch value equal to a target pitch value, the pitch averaging Bragg grating can be made to perform like a constant pitch Bragg grating having a fixed pitch at the target pitch value. The different pitch values can be multiples of the minimum placement resolution of a production tool to be used to produce the Bragg grating. The pitch averaging Bragg grating can be used in place of constant pitch Bragg gratings in optical devices and systems, such as DFB lasers, DBR lasers, optical spectral filters, multi-wavelength laser arrays, and WDM systems.

Abstract: A strained In.sub.y Ga.sub.l-y As layer is employed in a GaAs/Al.sub.x Ga.sub.l-x As transistor. Since the bandgap of In.sub.y Ga.sub.l-y As is much smaller than that of GaAs, there is no need for a troublesome large-mole-fraction of aluminum in the Al.sub.x Ga.sub.l-x As layer in order to maintain a large bandgap discontinuity. This and other advantages of the structure set forth result in devices having improved operating characteristics.