Binary group III-nitride based heterostructures: band offsets and transport properties
TL;DR: In this paper, the growth of non-polar III-nitrides has been an important subject due to its potential improvement on the efficiency of III-nodes-based opto-electronic devices.
Abstract: In the last few years, there has been remarkable progress in the development of group III-nitride based materials because of their potential application in fabricating various optoelectronic devices such as light emitting diodes, laser diodes, tandem solar cells and field effect transistors. In order to realize these devices, growth of device quality heterostructures are required. One of the most interesting properties of a semiconductor heterostructure interface is its Schottky barrier height, which is a measure of the mismatch of the energy levels for the majority carriers across the heterojunction interface. Recently, the growth of non-polar III-nitrides has been an important subject due to its potential improvement on the efficiency of III-nitride-based opto-electronic devices. It is well known that the c-axis oriented optoelectronic devices are strongly affected by the intrinsic spontaneous and piezoelectric polarization fields, which results in the low electron-hole recombination efficiency. One of the useful approaches for eliminating the piezoelectric polarization effects is to fabricate nitride-based devices along non-polar and semi-polar directions. Heterostructures grown on these orientations are receiving a lot of focus due to enhanced behaviour. In the present review article discussion has been carried out on the growth of III-nitride binary alloys and properties of GaN/Si, InN/Si, polar InN/GaN, and nonpolar InN/GaN heterostructures followed by studies on band offsets of III-nitride semiconductor heterostructures using the x-ray photoelectron spectroscopy technique. Current transport mechanisms of these heterostructures are also discussed.
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TL;DR: In this article, the hybrid gate-recessed structure and ferroelectric charge trapping/storage stacked structure were used in AlGaN/GaN enhancement-mode metaloxide-semiconductor high-electron mobility transistors (E-MOSHEMTs).
Abstract: The hybrid gate-recessed structure and ferroelectric charge trapping/storage stacked structure were used in AlGaN/GaN enhancement-mode metal–oxide–semiconductor high-electron mobility transistors (E-MOSHEMTs). The stacked structure consisted of a bottom 10-nm-thick Al2O3 tunnel oxide layer, a middle 4-nm-thick HfO2 charge trapping/storage layer, and a top 40-nm-thick LiNbO3 ferroelectric blocking layer. Using the postannealing process, a high polarized C+ domain of the pulsed laser-deposited LiNbO3 ferroelectric blocking layer was formed and the interface quality of the stacked structure was improved simultaneously. Consequently, positive threshold voltage for enhancement-mode operation was obtained. By studying the performances of the resulting devices, it was found that enhancement-mode behaviors were observed for initializing gate more than 5 V, and the threshold voltage of 1.6 V was obtained for initializing gate at 12 V. The high-frequency performances of the extrinsic unit gain cutoff frequency of 5.9 GHz and maximum oscillation frequency of 10.1 GHz were obtained. Furthermore, a low normalized noise power density of about $1.9\times 10^{-14}$ Hz−1 was achieved for the devices operating at a frequency of 10 Hz, a gate–source voltage of 5 V, and a drain–source voltage of 1 V.
2 citations
20 Dec 2017
Abstract: III-Nitride-based heterostructures are well suited for the fabrication of various optoelectronic devices such as light-emitting diodes (LEDs), laser diodes (LDs), high-power/high-frequency field-effect transistors (FETs), and tandem solar cells because of their inherent properties. However, the heterostructures grown along polar direction are affected by the presence of internal electric field induced by the existence of intrinsic spontaneous and piezoelectric polarizations. The internal electric field is deleterious for optoelectronic devices as it causes a spatial separation of electron and hole wave functions in the quantum wells, which thereby decreases the emission efficiency. The growth of III-nitride heterostructures in nonpolar or semipolar directions is an alternative option to minimize the piezoelectric polarization. The heterostructures grown on these orientations are receiving a lot of focus due to their potential improvement on the efficiency of optoelectronic devices. In the present chapter, the growth of polar and nonpolar III-nitride heterostructures using molecular beam epitaxy (MBE) system and their characterizations are discussed. The transport properties of the III-nitride heterostructure-based Schottky junctions are also included. In addition, their applications toward UV and IR detectors are discussed.
2 citations
Cites background from "Binary group III-nitride based hete..."
...The junction between InN and GaN exhibits a rectifying behavior which suggests an existence of Schottky barrier height at the junction [95, 96]....
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TL;DR: In this paper, high temperature nitridation of silicon substrates was applied to improve the quality of GaN layers, leading to stress relaxation and decrease of diffusion, thus improving the performance of the GaN epitaxial layers.
Abstract: Investigation of GaN epitaxial layers on silicon substrates is driven by high potential for fabrication of high efficiency and relatively low-cost electronic devises. Growth process of GaN layers on Si by molecular-beam epitaxy is complicated by mutual diffusion of Si and Ga and differences in thermal expansion coefficients and lattice parameters causing large number of defects. To improve the quality of GaN layers high temperature nitridation of silicon substrates was applied leading to stress relaxation and decrease of diffusion.
1 citations
1 citations
07 Dec 2022
TL;DR: In this paper , the tunability of the optical gain characteristics of the AlN/GaN/InAlN quantum well heterostructure under uniaxial and biaaxial pressures is reported.
Abstract: The tunability of the optical gain characteristics of the AlN/GaN/InAlN quantum well heterostructure under uniaxial and biaxial pressures is reported. To study the tunability, pressures on the designed heterostructure are applied in the range of 1–4 GPa along different orientations, i.e., (001), (100), and (110). Under these pressures, the gain characteristics are computed. To perform the calculations for the gain characteristics, the well‐known k⋅p method is adopted. The optical gain is computed under uniaxial and biaxial pressures and the results are analyzed thoroughly. Quantitatively speaking, the amount of pressure (1–4 GPa) along z‐direction (i.e., 001) is suitable to make significant enhancement in the peak gain (i.e., from ≈7000 to ≈8000 cm−1) with the variation in transition wavelength from ≈1347 to ≈1512 nm. While the (100) and (110) oriented pressures having the range 1–4 GPa reduce the peak gain from ≈7100 to ≈5800 cm−1, and from ≈3550 to ≈3410 cm−1, respectively. On comparison of the results, it is concluded that only z‐direction pressure is useful for enhancing the gain characteristics with fine tuning of the transition wavelengths. Consequently, the designed heterostructure can be tuned with enhanced peak gain having red shift wavelength.
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Book•
21 Mar 1997
TL;DR: The physics of gallium nitrides and related compounds GaN growth p-Type GaN obtained by electron beam irradiation n-Type GAN p-type GaN InGaN Zn and Si co-doped GaN double-heterostructure blue and blue green LEDs inGaN single-quantum-well structure LEDs room-temperature pulsed operation of laser diodes emission mechanisms of LEDs and LDs room temperature CW operation of InGAN MQW LDs latest results as discussed by the authors.
Abstract: Physics of gallium nitrides and related compounds GaN growth p-Type GaN obtained by electron beam irradiation n-Type GaN p-Type GaN InGaN Zn and Si co-doped InGaN/AlGaN double-heterostructure blue and blue-green LEDs inGaN single-quantum-well structure LEDs room-temperature pulsed operation of laser diodes emission mechanisms of LEDs and LDs room temperature CW operation of InGaN MQW LDs latest results - lasers with self-organized InGaN quantum dots
3,805 citations
TL;DR: In this article, the InGaN multi-quantum-well (MQW) structure was used for laser diodes, which produced 215mW at a forward current of 2.3
Abstract: InGaN multi-quantum-well (MQW) structure laser diodes (LDs) fabricated from III-V nitride materials were grown by metalorganic chemical vapor deposition on sapphire substrates. The mirror facet for a laser cavity was formed by etching of III-V nitride films without cleaving. As an active layer, the InGaN MQW structure was used. The InGaN MQW LDs produced 215 mW at a forward current of 2.3 A, with a sharp peak of light output at 417 nm that had a full width at half-maximum of 1.6 nm under the pulsed current injection at room temperature. The laser threshold current density was 4 kA/cm2. The emission wavelength is the shortest one ever generated by a semiconductor laser diode.
2,100 citations
TL;DR: In this paper, the Schottky barrier heights and band offsets for high dielectric constant oxides on Pt and Si were calculated and good agreement with experiment is found for barrier heights.
Abstract: Wide-band-gap oxides such as SrTiO3 are shown to be critical tests of theories of Schottky barrier heights based on metal-induced gap states and charge neutrality levels. This theory is reviewed and used to calculate the Schottky barrier heights and band offsets for many important high dielectric constant oxides on Pt and Si. Good agreement with experiment is found for barrier heights. The band offsets for electrons on Si are found to be small for many key oxides such as SrTiO3 and Ta2O5 which limit their utility as gate oxides in future silicon field effect transistors. The calculations are extended to screen other proposed oxides such as BaZrO3. ZrO2, HfO2, La2O3, Y2O3, HfSiO4, and ZrSiO4. Predictions are also given for barrier heights of the ferroelectric oxides Pb1−xZrxTiO3 and SrBi2Ta2O9 which are used in nonvolatile memories.
1,947 citations
PARC1
TL;DR: In this article, the group III elements of the semiconducting nitrides have been used for the fabrication of high-efficiency solid-state devices that emit green and blue light.
Abstract: Recent advances in fabrication technologies for the semiconducting nitrides of the group III elements have led to commercially available, high-efficiency solid-state devices that emit green and blue light Light-emitting diodes based on these materials should find applications in flat-panel displays, and blue and ultraviolet laser diodes promise high-density optical data storage and high-resolution printing
1,533 citations