Perspectives and recent advances of two-dimensional III-nitrides: Material synthesis and emerging device applications

Abstract

Both two-dimensional (2D) transitional metal dichalcogenides (TMDs) and III–V semiconductors have been considered as potential platforms for quantum technology. While 2D TMDs exhibit a large exciton binding energy, and their quantum properties can be tailored via heterostructure stacking, TMD technology is currently limited by the incompatibility with existing industrial processes. Conversely, III-nitrides have been widely used in light-emitting devices and power electronics but not leveraging excitonic quantum aspects. Recent demonstrations of 2D III-nitrides have introduced exciton binding energies rivaling TMDs, promising the possibility to achieve room-temperature quantum technologies also with III-nitrides. Here, we discuss recent advancements in the synthesis and characterizations of 2D III-nitrides with a focus on 2D free-standing structures and embedded ultrathin quantum wells. We overview the main obstacles in the material synthesis, vital solutions, and the exquisite optical properties of 2D III-nitrides that enable excitonic and quantum-light emitters.

Edge-Terminated AlGaN/GaN/AlGaN Multi-Quantum Well Impact Avalanche Transit Time Sources for Terahertz Wave Generation

“…Some recently developed techniques to deal with these challenges have already been mentioned in the earlier paragraph [40,41]. Ensuring uniformity in material composition and thickness across epitaxial layers is also critical for consistent device performance [42]. Any variations in material properties can lead to non-uniform device characteristics and reduced yield.…”

Impact of Charge Carrier Transfer and Strain Relaxation on Red-Emitting InGaN/GaN Heterostructures

“…III-nitride visible light emitters with micro- or submicrometer sizes are essential building blocks for next-generation displays and the emerging applications including augmented and virtual reality (AR/VR) systems. − Recently, significant progress has been made in high-efficiency blue and green microlight-emitting diodes (μLEDs) as well as multicolor integration, − while extensive efforts have been devoted in high-performance red-emitting μLEDs with high indium composition InGaN as the active regions. − However, the incorporation of high indium composition causes alloy substitutional disorder in the active region and reduces the exciton binding energy, which enhances the Auger recombination coefficient. Polar nitrides also suffer from quantum-confined Stark effect (QCSE) due to spontaneous and piezoelectric polarizations, which reduces the overlap of electron–hole wave functions and causes color instability as is depicted in Figure a.…”