Analysis of threading dislocations in void shape controlled GaN re-grown on hexagonally patterned mask-less GaN

Ali, Muhammad; Романов, А. Е.; Suihkonen, Sami; Svensk, Olli; Sintonen, Sakari; Sopanen, Markku; Lipsanen, Harri; Nevedomsky, V. N.; Берт, Н. А.; Odnoblyudov, M. A.; Bougrov, V. E.

doi:10.1016/j.jcrysgro.2012.01.047

Cited by 14 publications

(15 citation statements)

References 33 publications

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“…These unfilled gaps created dislocations or pits during coalescence. A similar behavior was also observed in [14].…”

Section: Methodssupporting

confidence: 84%

“…Numerous hexagonal etching pits were observed on the surface after wet etching. These etching pits were produced by the TDs propagating to the surface of GaN, which originated from the interface between GaN and the substrate or the coalescence interface [14]. The EPDs of the samples were calculated over a 10-× 10-μm 2 scanning area of sample-R, sample-1, and sample-2.…”

Section: Methodsmentioning

confidence: 99%

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Enabling High-Injection Current Light-Emitting Diodes Prepared on 10-$\mu \text{m}$ -Thick GaN Films Grown by Hydride Vapor Phase Epitaxy

Chen

Chang

Kuo

2015

IEEE Trans. Electron Devices

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In this paper, we successfully introduced the sputtered AlN/patterned sapphire substrate template into hydride vapor phase epitaxy (HVPE) using a two-step growth method. This method simplified the procedure, realized uninterrupted growth, and improved the crystal quality of GaN films. The effects of light-emitting diodes (LEDs) grown on a 10-µm-thick GaN film through HVPE were also compared with those of the LEDs grown on a 2.4-µm-thick GaN film through metal organic chemical vapor deposition (MOCVD). Compared with the LEDs grown on the 2.4-µm-thick GaN film through MOCVD, the LEDs grown on the 10-µm-thick GaN film through HVPE had significantly enhanced light output power (3.24-4.79 mW) and extended saturation current (300-355 mA). These improvements of the LEDs were attributed to the better thermal conductivities and better crystal quality of the 10-µm-thick GaN film through HVPE than those of the 2.4-µm-thick GaN film through MOCVD.Index Terms-AlN, hydride vapor phase epitaxy (HVPE), light-emitting diode (LED), patterned sapphire substrate (PSS).

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“…These unfilled gaps created dislocations or pits during coalescence. A similar behavior was also observed in [14].…”

Section: Methodssupporting

confidence: 84%

Section: Methodsmentioning

confidence: 99%

Enabling High-Injection Current Light-Emitting Diodes Prepared on 10-$\mu \text{m}$ -Thick GaN Films Grown by Hydride Vapor Phase Epitaxy

Chen

Chang

Kuo

2015

IEEE Trans. Electron Devices

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“…Ali et al also showed that void shapes can be controlled using different hexagonally patterned maskless GaN templates. The TDs near the voids were bent differently with the various hexagonally patterned maskless GaN templates [25,26]. Martinez-Criado et al used the ELOG technique to embed air voids into GaN substrate and recommended the stress relaxation and crack suppression [16].…”

Section: Introductionmentioning

confidence: 99%

Void Shapes Controlled by Using Interruption-Free Epitaxial Lateral Overgrowth of GaN Films on Patterned SiO₂AlN/Sapphire Template

Chen

Kuo

Chang

et al. 2014

International Journal of Photoenergy

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GaN epitaxial layers with embedded air voids grown on patterned SiO2AlN/sapphire templates were proposed. Using interruption-free epitaxial lateral overgrowth technology, we realized uninterrupted growth and controlled the shape of embedded air voids. These layers showed improved crystal quality using X-ray diffraction and measurement of etching pits density. Compared with conventional undoped-GaN film, the full width at half-maximum of the GaN (0 0 2) and (1 0 2) peaks decreased from 485 arcsec to 376 arcsec and from 600 arcsec to 322 arcsec, respectively. Transmission electron microscopy results showed that the coalesced GaN growth led to bending threading dislocation. We also proposed a growth model based on results of scanning electron microscopy.

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“…1,5,6 Therefore, large efforts were made primarily in order to reduce the concentration of the threading dislocations by influencing their line direction by, e.g., epitaxial lateral overgrowth, patterning with semipolar facets, and/or interlayers. [7][8][9][10][11][12][13][14][15][16][17] Some of the threading dislocations do, however, still continue to propagate along growth direction, penetrating through the whole epitaxial layers. Such threading dislocations as well as dislocations which can nucleate during growth instabilities, may give rise to three-dimensional inverted pyramidal pits (also called v-shaped defects), which occur at the intersection points of dislocations on the growth surface.…”

mentioning

confidence: 99%

Meandering of overgrown v-shaped defects in epitaxial GaN layers

Weidlich

Schnedler

Portz

et al. 2014

Applied Physics Letters

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The meandering of v-shaped defects in GaN(0001) epitaxial layers is investigated by cross-sectional scanning tunneling microscopy. The spatial position of v-shaped defects is mapped on (101¯0) cleavage planes using a dopant modulation, which traces the overgrown growth front. Strong lateral displacements of the apex of the v-shaped defects are observed. The lateral displacements are suggested to be induced by the meandering of threading dislocations present in the v-shaped defects. The meandering of the dislocation is attributed to interactions with inhomogeneous strain fields.

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Analysis of threading dislocations in void shape controlled GaN re-grown on hexagonally patterned mask-less GaN

Cited by 14 publications

References 33 publications

Enabling High-Injection Current Light-Emitting Diodes Prepared on 10-$\mu \text{m}$ -Thick GaN Films Grown by Hydride Vapor Phase Epitaxy

Enabling High-Injection Current Light-Emitting Diodes Prepared on 10-$\mu \text{m}$ -Thick GaN Films Grown by Hydride Vapor Phase Epitaxy

Void Shapes Controlled by Using Interruption-Free Epitaxial Lateral Overgrowth of GaN Films on Patterned SiO₂AlN/Sapphire Template

Meandering of overgrown v-shaped defects in epitaxial GaN layers

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Analysis of threading dislocations in void shape controlled GaN re-grown on hexagonally patterned mask-less GaN

Cited by 14 publications

References 33 publications

Enabling High-Injection Current Light-Emitting Diodes Prepared on 10-$\mu \text{m}$ -Thick GaN Films Grown by Hydride Vapor Phase Epitaxy

Enabling High-Injection Current Light-Emitting Diodes Prepared on 10-$\mu \text{m}$ -Thick GaN Films Grown by Hydride Vapor Phase Epitaxy

Void Shapes Controlled by Using Interruption-Free Epitaxial Lateral Overgrowth of GaN Films on Patterned SiO2AlN/Sapphire Template

Meandering of overgrown v-shaped defects in epitaxial GaN layers

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Product

Resources

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Void Shapes Controlled by Using Interruption-Free Epitaxial Lateral Overgrowth of GaN Films on Patterned SiO₂AlN/Sapphire Template