Effect of middle temperature intermediate layer on crystal quality of AlGaN grown on sapphire substrates by metalorganic chemical vapor deposition

Tsukihara, Masashi; Sumiyoshi, Kazuhide; Okimoto, Takashi; Kataoka, Keita; Kawamichi, S.; Nishino, Katsushi; Naoi, Yoshiki; Sakai, Shiro

doi:10.1016/j.jcrysgro.2006.11.011

Cited by 7 publications

(6 citation statements)

References 16 publications

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“…To address those issues, several techniques are currently being pursued, including epitaxial lateral overgrowth [6] , alternate gas feeding in growth process [7] , and the introduction of AlN/AlGaN superlattices (SLs) as an interlayer [8][9][10] . AlN/AlGaN SLs partly relieves the lattice mismatch between AlGaN and AlN/sapphire templates, reducing the driving force of generating dislocations [11] . It also modulates stress and makes dislocations bend or annihilate at SLs interfaces [12] .…”

Section: Introductionmentioning

confidence: 99%

The effect of AlN/AlGaN superlattices on crystal and optical properties of AlGaN epitaxial layers

Zhang

Chen

et al. 2017

J. Semicond.

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We investigate the effect of AlN/AlGaN superlattices (SLs) on crystal and optical properties of AlGaN epitaxial layers. The result indicates that the crystal quality of AlGaN layers is consistent within a wide range of SLs thicknesses, while the optical properties are opposite. With SLs thickness decreasing from 20/44 to 17/36 and 15/29 nm, the full-width at half maximum of X-ray rocking curves for (0002)-and ()-plane of n-AlGaN layers grown on SLs are consistent of around 250 arcsec and 700 arcsec, respectively. Meanwhile, the center of the low optical transmittance band decreases from 326 to 279 nm and less than 266 nm as the SLs thickness decreases. 280 nm deep ultraviolet light-emitting diodes (DUV-LEDs) structures are further regrown on the n-AlGaN layers. The electroluminescent intensities of samples are 30% higher than that of the sample whose low optical transmittance band appears around 279 nm. Optical simulations reveal that the SLs acts as distributed Bragg reflectors, thus less photons of the corresponding wavelength escape from the sapphire backside.

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Section: Introductionmentioning

confidence: 99%

The effect of AlN/AlGaN superlattices on crystal and optical properties of AlGaN epitaxial layers

Zhang

Chen

et al. 2017

J. Semicond.

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“…Meanwhile, AlGaN epitaxy requires temperatures in excess of 1300 °C. The large thermal expansion mismatch in the AlGaN/AlN/sapphire structure results in heat-induced stress, which is released by dislocations 89 , 91 – 93 . Additionally, because the surface adhesion coefficient of Al atoms is much higher than that of Ga atoms, dense islands tend to form during nucleation growth.…”

Section: Epitaxial Growth and Doping Of Alganmentioning

confidence: 99%

Progress on AlGaN-based solar-blind ultraviolet photodetectors and focal plane arrays

et al. 2021

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Solar-blind ultraviolet (UV) photodetectors (PDs) have attracted tremendous attention in the environmental, industrial, military, and biological fields. As a representative III-nitride material, AlGaN alloys have broad development prospects in the field of solar-blind detection due to their superior properties, such as tunable wide bandgaps for intrinsic UV detection. In recent decades, a variety of AlGaN-based PDs have been developed to achieve high-precision solar-blind UV detection. As integrated optoelectronic technology advances, AlGaN-based focal plane arrays (FPAs) are manufactured and exhibit outstanding solar-blind imaging capability. Considering the rapid development of AlGaN detection techniques, this paper comprehensively reviews the progress on AlGaN-based solar-blind UV PDs and FPAs. First, the basic physical properties of AlGaN are presented. The epitaxy and p-type doping problems of AlGaN alloys are then discussed. Diverse PDs, including photoconductors and Schottky, metal–semiconductor–metal (MSM), p-i-n, and avalanche photodiodes (APDs), are demonstrated, and the physical mechanisms are analyzed to improve device performance. Additionally, this paper summarizes imaging technologies used with AlGaN FPAs in recent years. Benefiting from the development of AlGaN materials and optoelectronic devices, solar-blind UV detection technology is greeted with significant revolutions.

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“…In general, the Al composition of Al x Ga 1−x N must be over 40% to effectively fabricate DUV PDs, whereas the decisive difficulty in epitaxially growing high-Al-content AlGaN with high crystalline quality remains challenging, which is ascribed to structural defects derived from the lattice mismatch and thermal expansion mismatch in the epitaxial structure. 18,19 Ga 2 O 3 has been emerging as one of the most promising candidates for DUV PDs owing to its naturally ultrawide bandgap with a cut-off wavelength below 280 nm. 4,[20][21][22] Benefiting from the similar electronic configuration between Ga and Al atoms and the much larger bandgap of Al 2 O 3 , it is feasible to prepare (Al x Ga 1−x ) 2 O 3 alloys with bandgaps modulated from 4.9 to 8.8 eV.…”

Section: Introductionmentioning

confidence: 99%

High-performance (Al_0.4Ga_0.6)₂O₃/Al_0.32Ga_0.68N-based UVC/UVB tunable dual-band photodetectors

Wu,

Tian

et al. 2024

CrystEngComm

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Effect of middle temperature intermediate layer on crystal quality of AlGaN grown on sapphire substrates by metalorganic chemical vapor deposition

Cited by 7 publications

References 16 publications

The effect of AlN/AlGaN superlattices on crystal and optical properties of AlGaN epitaxial layers

The effect of AlN/AlGaN superlattices on crystal and optical properties of AlGaN epitaxial layers

Progress on AlGaN-based solar-blind ultraviolet photodetectors and focal plane arrays

High-performance (Al_0.4Ga_0.6)₂O₃/Al_0.32Ga_0.68N-based UVC/UVB tunable dual-band photodetectors

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Effect of middle temperature intermediate layer on crystal quality of AlGaN grown on sapphire substrates by metalorganic chemical vapor deposition

Cited by 7 publications

References 16 publications

The effect of AlN/AlGaN superlattices on crystal and optical properties of AlGaN epitaxial layers

The effect of AlN/AlGaN superlattices on crystal and optical properties of AlGaN epitaxial layers

Progress on AlGaN-based solar-blind ultraviolet photodetectors and focal plane arrays

High-performance (Al0.4Ga0.6)2O3/Al0.32Ga0.68N-based UVC/UVB tunable dual-band photodetectors

Contact Info

Product

Resources

About

High-performance (Al_0.4Ga_0.6)₂O₃/Al_0.32Ga_0.68N-based UVC/UVB tunable dual-band photodetectors