Free-standing semipolar III-nitride quantum well structures grown on chemical vapor deposited graphene layers

Pc, Gupta; Rahman, Atikur; Hatui, Nirupam; Parmar, Jayesh B.; Chalke, Bhagyashree A.; Bapat, Rudheer; Purandare, S. C.; Deshmukh, Mandar M.; Bhattacharya, Arnab

doi:10.1063/1.4827539

Cited by 27 publications

(24 citation statements)

References 23 publications

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“…15 Here we report the growth and characterization of highly oriented NbN thin films with T C ∼14 K on large-area chemical vapor deposited (CVD) graphene. Growth on graphene layers transferred onto SiO 2 -coated silicon wafers provides an easy route for delamination 16 of the graphene layer along with the deposited film. This enables the release of the NbN film from the substrate, thus allowing flexible, free-standing NbN layers to be obtained.…”

mentioning

confidence: 99%

Highly oriented, free-standing, superconducting NbN films growth on chemical vapor deposited graphene

Saraswat¹,

Pc²,

Bhattacharya³

et al. 2014

APL Materials

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NbN films are grown on chemical vapor deposited graphene using dc magnetron sputtering. The orientation and transition temperature of the deposited films is studied as a function of substrate temperature. A superconducting transition temperature of 14 K is obtained for highly oriented (111) films grown at substrate temperature of 150 °C, which is comparable to epitaxial films grown on MgO and sapphire substrates. These films show a considerably high upper critical field of ∼33 T. In addition, we demonstrate a process for obtaining flexible, free-standing NbN films by delaminating graphene from the substrate using a simple wet etching technique. These free-standing NbN layers can be transferred to any substrate, potentially enabling a range of novel superconducting thin-film applications.

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confidence: 99%

Highly oriented, free-standing, superconducting NbN films growth on chemical vapor deposited graphene

Saraswat¹,

Pc²,

Bhattacharya³

et al. 2014

APL Materials

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“…Recently, graphene has been used as a buffer layer for the van der Waals epitaxy growth of a GaN epilayer to overcome the substantial thermal expansion coefficient and in‐plane lattice constant mismatch between the GaN epilayer and sapphire substrate (c‐Al 2 O 3 ), which causes a significant strain in the GaN epilayer. However, because the graphene surface lacks dangling bonds, the nucleation of nitrides on graphene is restricted, and clusters are easily formed …”

Section: Introductionmentioning

confidence: 99%

Transferable GaN Enabled by Selective Nucleation of AlN on Graphene for High‐Brightness Violet Light‐Emitting Diodes

Jia

Ning

Zhang

et al. 2019

Advanced Optical Materials

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some outstanding features, such as a high carrier mobility, [8][9][10] a high thermal conductivity, [11] flexibility, [12] and visible transparency. [13,14] Moreover, it can be used as a removable layer for the epitaxial growth of III-Ns, thus providing the foundation for a new field of transferable and flexible LEDs. [15,16] Recently, graphene has been used as a buffer layer for the van der Waals epitaxy growth of a GaN epilayer to overcome the substantial thermal expansion coefficient and in-plane lattice constant mismatch between the GaN epilayer and sapphire substrate (c-Al 2 O 3 ), which causes a significant strain in the GaN epilayer. However, because the graphene surface lacks dangling bonds, the nucleation of nitrides on graphene is restricted, and clusters are easily formed. [17,18] In this study, theoretical calculations using first-principles calculations based on density functional theory (DFT) were carefully conducted to further examine the formation mechanism of AlN and GaN on graphene. We found that AlN selectively grows on graphene, and we identified its optimal nucleation site. We obtained the adsorption probability of Al atoms at various positions on the graphene CC ring and found that the hollow of the complete graphene CC ring and the center of the broken graphene CC ring are the best adsorption positions under different states of the graphene. Based on this, we innovatively inserted an AlN composite nucleation layer between graphene and GaN, which was grown by metal organic chemical vapor deposition (MOCVD) using time-distributed and constant-pressure (TDCP) growth. The growth process for AlN is divided into three stages. Under the same pressure, different flow rates, and growth temperatures are used for each stage. By controlling the growth time at different flow rates, an AlN composite nucleation layer on graphene can be formed. By introducing the selective nucleation of an AlN composite layer and graphene, the biaxial stress of the GaN film was effectively released, leading to transferable and low density dislocations in the GaN film and the In 0.1 Ga 0.9 N/GaN multiple quantum well structures. Note that LEDs with an ultrahigh light output power (LOP) of 260.5 mW at a small current of 560 mA were achieved. Our study demonstrates a practical application of an AlN composite nucleation layer grown on graphene that may result in A transferable GaN epilayer is grown on an improved aluminum nitride (AlN)/graphene composite substrate. In this study, theoretical calculations using first-principles calculations based on density functional theory are carefully conducted to further examine the formation mechanism of AlN on graphene. AlN selectively grows on graphene via its optimal nucleation site, which leads to the selective nucleation of AlN on graphene via quasi-van der Waals epitaxy. Thus, an AlN composite nucleation layer is innovatively inserted between graphene and GaN, using the time-distributed and constant-pressure growth method by metal organic chemical vapor deposition. Moreover, a hi...

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“…Meanwhile, traditional epitaxial films on rigid substrates are difficult to extend for flexible devices, which also limits their application . These obstacles can be solved by introducing graphene as an insertion layer for GaN growth . Graphene, a 2D material with many fascinating properties, has attracted increasing interest from researchers in physics, materials science, and biology .…”

Section: Introductionmentioning

confidence: 99%

Transferable GaN Films on Graphene/SiC by van der Waals Epitaxy for Flexible Devices

Liu¹,

Cao³

et al. 2019

Physica Status Solidi (a)

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Van der Waals epitaxy (vdWE) of GaN films on two-dimensional (2D) materials can overcome a lattice mismatch during crystalline growth. Moreover, this type of epitaxy allows the GaN films to be released from 2D materials because of the weak van der Waals force. However, it is difficult to directly grow a single-crystalline film on graphene. Here, using metal-organic chemical vapor deposition (MOCVD), transferable single-crystalline GaN films are synthesized on multilayer graphene (MLG)/SiC. The films exhibit a flat and continuous surface morphology and c-axis orientation. Moreover, the GaN films are released from the graphene and transferred to flexible substrates by direct mechanical exfoliation. Furthermore, flexible ultraviolet (UV) photosensitive devices are fabricated and show excellent photoelectric performance in the UV-range. This research lays a foundation for the application of GaN films in foldable-display and flexible-devices.

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Free-standing semipolar III-nitride quantum well structures grown on chemical vapor deposited graphene layers

Cited by 27 publications

References 23 publications

Highly oriented, free-standing, superconducting NbN films growth on chemical vapor deposited graphene

Highly oriented, free-standing, superconducting NbN films growth on chemical vapor deposited graphene

Transferable GaN Enabled by Selective Nucleation of AlN on Graphene for High‐Brightness Violet Light‐Emitting Diodes

Transferable GaN Films on Graphene/SiC by van der Waals Epitaxy for Flexible Devices

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