Quantum engineering of non-equilibrium efficient p-doping in ultra-wide band-gap nitrides

Abstract

Ultra-wide band-gap nitrides have huge potential in micro- and optoelectronics due to their tunable wide band-gap, high breakdown field and energy density, excellent chemical and thermal stability. However, their application has been severely hindered by the low p-doping efficiency, which is ascribed to the ultrahigh acceptor activation energy originated from the low valance band maximum. Here, a valance band modulation mode is proposed and a quantum engineering doping method is conducted to achieve high-efficient p-type ultra-wide band-gap nitrides, in which GaN quantum-dots are buried in nitride matrix to produce a new band edge and thus to tune the dopant activation energy. By non-equilibrium doping techniques, quantum engineering doped AlGaN:Mg with Al content of 60% is successfully fabricated. The Mg activation energy has been reduced to about 21 meV, and the hole concentration reaches higher than 1018 cm−3 at room temperature. Also, similar activation energies are obtained in AlGaN with other Al contents such as 50% and 70%, indicating the universality of the quantum engineering doping method. Moreover, deep-ultraviolet light-emission diodes are fabricated and the improved performance further demonstrates the validity and merit of the method. With the quantum material growth techniques developing, this method would be prevalently available and tremendously stimulate the promotion of ultra-wide band-gap semiconductor-based devices.

Point Defects in Monolayer h-AlN as Candidates for Single-Photon Emission

“…Developing more materials is necessary to further improve the performance of SPE sources. 2D III-nitrides semiconductors show great potential to provide more options in this field not only due to the chemical comparability to h -BN but also due to the mature development of their bulk phases, such as deep UV light-emitting diodes, , lasers diodes, , and transistors . Following theoretically confirming the good thermodynamic stability of hexagonal AlN ( h -AlN), Tsipas et al, Mansurov et al, and Malin et al had experimentally realized h -AlN via molecular beam epitaxy. − The defective monolayer h -AlN is highly expected to be a good host material for qubits due to its similarity to h -BN.…”

Regulating the valence level arrangement of high-Al-content AlGaN quantum wells using additional potentials with Mg doping

“…Impurity doping turns out to be advantageous for regulating the coupling energy by introducing local lattice variation as well as additional Coulomb potential to QWs due to the Coulomb interaction between carriers and the charged dopant atoms. The Mg atom commonly serves as the acceptor for p-type doping in group-III nitrides, [29][30][31] and previous studies have reported that using Mg doping in InGaN MQWs can improve the hole injection and crystal quality, thus enhancing the performance of InGaN LEDs. 32,33 When Mg is doped in nitride via the substitution of Ga or Al, a local positive center is formed due to the lack of a single valence electron.…”

Drive High Power UVC‐LED Wafer into Low‐Cost 4‐Inch Era: Effect of Strain Modulation

“…The explosion of COVID‐19 has been greatly impacting the world and intensively activated the development of light‐emitting diodes (LEDs) at the ultraviolet‐C (wavelength ≤ 280 nm) emission range. It has been confirmed encouragingly perspective for the ultra‐fast sterilization toward SARS‐CoV‐2 within 1 s. [ 1–7 ] In the past decades, in order to fabricate high‐performance UVC‐LED, various techniques have been proposed to seek excellent crystalline AlN templates on UVC‐transparent sapphire substrates. [ 8–19 ] In spite that the epitaxial lateral overgrowth (ELOG) [ 4,20–22 ] and high‐temperature annealing (HTA) [ 23,24 ] strategies act as landmarks to fulfill the demands, both of them expose respective fatal shortcomings.…”