Mesoporous GaN for Photonic Engineering—Highly Reflective GaN Mirrors as an Example

Zhang, Cheng; Park, Sung Hyun; Chen, Danti; Lin, Da-Wei; Xiong, Wen; Kuo, Hao Chung; Lin, Chia Feng; Cao, Hui; Han, Jung

doi:10.1021/acsphotonics.5b00216

Cited by 146 publications

(125 citation statements)

References 38 publications

(79 reference statements)

Supporting

Mentioning

119

Contrasting

Order By: Relevance

“…The EC etching process carried out in a constant voltage mode (with a DC bias of 6 V) and controlled by monitoring and recording the etching current signal at room temperature without UV illumination. The EC porosification process begins with the oxidation of the alternating n + -GaN layers by localised injection of holes upon the application of a positive anodic bias, and localised dissolution of such oxide layer in the acid-based electrolyte will result in the formation of mesoporous structure3234. The end of the anodisation process is reached when the etching current drops to the base line level, indicating that all the n + -GaN layers have been etched and transformed into mesoporous GaN layers, typically after 30 minutes.…”

Section: Ec Porosification and Structural Characterization Of Gan/mp-mentioning

confidence: 99%

“…2e, that mesopores are formed independent of the position of the defects in the n + -GaN layers. However, we notice that the NID GaN layers seem to have also been slightly etched at various locations (marked by the white circles), implying that in additional to the usual lateral etching pathways32, the EC porosification mechanism might involve another vertical etching component, which may be defect related. We estimated the density of such vertical etching pathways to be ~2 × 10 9 cm −2 based on cross-sectional STEM images over a relatively large area ~2.5 μm (distance) × 0.15 μm (thickness of the TEM specimen) (see Figure S1 in Supplementary Information), which is much lower than the density of stacking faults and dislocations present in the GaN pseudo-substrate35.…”

Section: Ec Porosification and Structural Characterization Of Gan/mp-mentioning

confidence: 99%

“…Zhang et al . have proposed an electrochemical (EC) method for the fabrication of porous GaN DBRs on c -plane GaN32. The EC process utilises the epitaxial growth of lattice-matched highly n-doped and undoped GaN layers, and porosification of the n-doped layers33.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Wafer-scale Fabrication of Non-Polar Mesoporous GaN Distributed Bragg Reflectors via Electrochemical Porosification

Zhu

Liu

Ding

et al. 2017

Sci Rep

View full text Add to dashboard Cite

Distributed Bragg reflectors (DBRs) are essential components for the development of optoelectronic devices. For many device applications, it is highly desirable to achieve not only high reflectivity and low absorption, but also good conductivity to allow effective electrical injection of charges. Here, we demonstrate the wafer-scale fabrication of highly reflective and conductive non-polar gallium nitride (GaN) DBRs, consisting of perfectly lattice-matched non-polar (11–20) GaN and mesoporous GaN layers that are obtained by a facile one-step electrochemical etching method without any extra processing steps. The GaN/mesoporous GaN DBRs exhibit high peak reflectivities (>96%) across the entire visible spectrum and wide spectral stop-band widths (full-width at half-maximum >80 nm), while preserving the material quality and showing good electrical conductivity. Such mesoporous GaN DBRs thus provide a promising and scalable platform for high performance GaN-based optoelectronic, photonic, and quantum photonic devices.

show abstract

Section: Ec Porosification and Structural Characterization Of Gan/mp-mentioning

confidence: 99%

Section: Ec Porosification and Structural Characterization Of Gan/mp-mentioning

confidence: 99%

See 1 more Smart Citation

Wafer-scale Fabrication of Non-Polar Mesoporous GaN Distributed Bragg Reflectors via Electrochemical Porosification

Zhu

Liu

Ding

et al. 2017

Sci Rep

View full text Add to dashboard Cite

show abstract

“…The resonant cavity effect of III-nitride thin-film flip-chip light-emitting diodes with anatase TiO 2 microsphere array were reported 20 . Nanoporous GaN material has been reported as an effective low refractive index for the DBR structure applications [21][22][23] .In this paper, InGaN LED structure with bottom nanoporous-GaN DBR structure has been fabricated. Twelve pairs of n + -GaN:Si/undoped-GaN epitaxial stack structure were grown for the following selective electrochemically (EC) etching process.…”

mentioning

confidence: 99%

mentioning

confidence: 99%

InGaN light-emitting diodes with embedded nanoporous GaN distributed Bragg reflectors

Shieh

Jhang

Huang

et al. 2015

Appl. Phys. Express

Self Cite

View full text Add to dashboard Cite

InGaN light emitting diodes (LED) structure with an embedded 1/4λ-stack nanoporous-GaN/undopedGaN distributed Bragg reflectors (DBR) structure have been demonstrated. Si-heavily doped GaN epitaxial layers (n + -GaN) in the 12-period n + -GaN/u-GaN stack structure are transformed into low refractive index nanoporous GaN structure through the doping-selective electrochemical wet etching process. The central wavelength of the nanoporous DBR structure was located at 442.3 nm with a 57 nm linewidth and a 97.1% peak reflectivity. The effective cavity length (6.0λ), the effective penetration depth (278 nm) in the nanoporous DBR structure, and InGaN active layer matching to Fabry-Pérot mode order 12 were observed in the far-field photoluminescence radiative spectra. High electroluminescence emission intensity and line-width narrowing effect were measured in the DBR-LED compared with the non-treated LED structure. Non-linear emission intensity and line-width reducing effect, from 11.8 nm to 0.73 nm, were observed by increasing the laser excited power. Resonant cavity effect was observed in the InGaN LED with bottom nanoporous-DBR and top GaN/air interface.Gallium nitride (GaN) materials have considerable in optoelectronic devices such as light-emitting diodes (LEDs), laser diodes (LD) 1 , and vertical cavity surface emitting lasers (VCSEL) 2 . High reflectivity distributed Bragg reflectors (DBR) structure, short cavity thickness 3-5 , high transparence conductive layer, efficient transverse current spreading, small current confinement aperture, and resonant cavity controled in the nitride VCSEL need to be improved. Leonard et al. reported on violet nonpolar III-nitride VCSELs with a tunnel junction intracavity contact 6 and an Al ion implanted aperture 7 . The epitaxial AlGaN/GaN stack 8,9 and AlN/GaN stacks 10,11 structures had been reported for the bottom epitaxial DBRs in GaN-based VCSEL devices. Large lattice mismatch and low refractive index different of the stack structures are the challenges for the epitaxial DBR structures with long epitaxial growth time. The AlInN/GaN DBR structure 12,13 is lattice matched to GaN material, but the growth of AlInN layer remains a challenge in InGaN-based LED structures. To realize the high reflectivity with less pairs of stack structure, the air-gap/GaN DBR structures with large refractive index different had been fabricated through selectively anodized processe 14,15 , and thermal decomposition techniques [16][17][18] . But, the low mechanical strength and the tiny high reflective area remains a challenge for the photonic device fabrication. Plawsky et al. 19 . reported the nanoporous material for the photonics through the evaporation induced self-assembly process and oblique or glancing angle deposition. The resonant cavity effect of III-nitride thin-film flip-chip light-emitting diodes with anatase TiO 2 microsphere array were reported 20 . Nanoporous GaN material has been reported as an effective low refractive index for the DBR structure applications [21][22][23] .In this pa...

show abstract

High‐Q, Low‐Threshold Monolithic Perovskite Thin‐Film Vertical‐Cavity Lasers

et al. 2017

Self Cite

View full text Add to dashboard Cite

A vertical-cavity surface-emitting perovskite laser is achieved using a microcavity configuration where CH NH PbI thin solid films are embedded within a custom GaN-based high-quality (Q-factor) resonator. This single-mode perovskite laser reaches a low threshold (≈7.6 µJ cm ) at room temperature and emits spatially coherent Gaussian laser beams. The devices allow direct access to the study of perovskite gain dynamics and material robustness.

show abstract

Mesoporous GaN for Photonic Engineering—Highly Reflective GaN Mirrors as an Example

Abstract: Porous medium is a special type of material where voids are created in a solid medium. The introduction of pores into a bulk solid can profoundly affect its physical properties and enable

Cited by 146 publications

References 38 publications

Wafer-scale Fabrication of Non-Polar Mesoporous GaN Distributed Bragg Reflectors via Electrochemical Porosification

Wafer-scale Fabrication of Non-Polar Mesoporous GaN Distributed Bragg Reflectors via Electrochemical Porosification

InGaN light-emitting diodes with embedded nanoporous GaN distributed Bragg reflectors

High‐Q, Low‐Threshold Monolithic Perovskite Thin‐Film Vertical‐Cavity Lasers

Contact Info

Product

Resources

About