Fabrication and repair of GaN nanorods by plasma etching with self-assembled nickel nanomasks

2021 ◽  
Author(s):  
Shiying Zhang ◽  
Lei Zhang ◽  
Yueyao Zhong ◽  
Guodong Wang ◽  
Qingjun Xu
Keyword(s):  
Inductively Coupled Plasma ◽  
Average Diameter ◽  
Etching Time ◽  
X Ray Diffraction ◽  
Plasma Etch ◽  
Inductively Coupled ◽  
Icp Etching ◽  
Self Organized ◽  
Gan Film ◽  
Koh Etching

High crystal quality GaN nanorod arrays were fabricated by inductively coupled plasma (ICP) etching using self-organized nickel (Ni) nano-islands mask on GaN film and subsequent repaired process including annealing in ammonia and KOH etching. The Ni nano-islands have been formed by rapid thermal annealing, whose density, shape, and dimensions were regulated by annealing temperature and Ni layer thickness. The structural and optical properties of the nanorods obtained from GaN epitaxial layers were comparatively studied by high-resolution X-ray diffraction (HRXRD), Raman spectroscopy and photoluminescence (PL). The results indicate that damage induced by plasma can be successfully healed by annealing in NH3 at 900 °C. The average diameter of the as-etched nanorod was effectively reduced and the plasma etch damage was removed after a wet treatment process in a KOH solution. It was found that the diameter of the GaN nanorod was continuously reduced and the PL intensity first increased, then reduced and finally increased as the KOH etching time sequentially increased.

scholarly journals A Selective Etching Route for Large-Scale Fabrication of β-Ga2O3 Micro-/Nanotube Arrays

Nanomaterials ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 3327
Author(s):  
Shan Ding ◽  
Liying Zhang ◽  
Yuewen Li ◽  
Xiangqian Xiu ◽  
Zili Xie ◽  
...  
Keyword(s):  
Thermal Oxidation ◽  
Inductively Coupled Plasma ◽  
Large Scale ◽  
Selective Etching ◽  
Nanowire Arrays ◽  
Nanotube Arrays ◽  
Inductively Coupled ◽  
Icp Etching ◽  
Self Organized ◽  
Vertically Aligned

In this paper, based on the different etching characteristics between GaN and Ga2O3, large-scale and vertically aligned β-Ga2O3 nanotube (NT) and microtube (MT) arrays were fabricated on the GaN template by a facile and feasible selective etching method. GaN micro-/nanowire arrays were prepared first by inductively coupled plasma (ICP) etching using self-organized or patterning nickel masks as the etching masks, and then the Ga2O3 shell layer converted from GaN was formed by thermal oxidation, resulting in GaN@Ga2O3 micro-/nanowire arrays. After the GaN core of GaN@Ga2O3 micro-/nanowire arrays was removed by ICP etching, hollow Ga2O3 tubes were obtained successfully. The micro-/nanotubes have uniform morphology and controllable size, and the wall thickness can also be controlled with the thermal oxidation conditions. These vertical β-Ga2O3 micro-/nanotube arrays could be used as new materials for novel optoelectronic devices.

Study of Mesa Etching for Infrared Detector Based on InAs/GaSb Superlattice

2013 ◽  
Vol 760-762 ◽  
pp. 137-140 ◽  
Author(s):  
Jie Guo ◽  
Rui Ting Hao ◽  
Qian Run Zhao ◽  
Shi Qing Man
Keyword(s):  
Inductively Coupled Plasma ◽  
Infrared Detector ◽  
Etching Rate ◽  
Etching Time ◽  
Rf Power ◽  
Etching Technique ◽  
Inductively Coupled ◽  
Icp Etching ◽  
Surface Leakage ◽  
Photovoltaic Detector

InAs/GaSb superlattice in infrared detector was grown on GaSb substrates by molecular beam epitaxy technique. Using inductively coupled plasma (ICP) etching technique and Cl2/Ar etching gas, the smooth mesa of the device was formed. The influence of etching time, Cl2 percent and RF power on the etching rate and the surface morphology of InAs bulk, GaSb bulk materials and superlattice were studied. It showed that the etching rate of InAs was lower than that of GaSb and the etching surface was smooth at Cl2 in the range of 20%~40%. The results will benefit to forming ohm contact and decrease surface leakage current in the photovoltaic detector.

scholarly journals High-efficiency method for recycling lithium from spent LiFePO4 cathode

2020 ◽  
Vol 9 (1) ◽  
pp. 1586-1593
Author(s):  
Tingting Yan ◽  
Shengwen Zhong ◽  
Miaomiao Zhou ◽  
Xiaoming Guo ◽  
Jingwei Hu ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
High Efficiency ◽  
Optical Emission ◽  
Extraction Process ◽  
Emission Spectrometry ◽  
X Ray Diffraction ◽  
Inductively Coupled ◽  
Moisture Analysis ◽  
Lifepo4 Cathode ◽  
Solid Liquid

Abstract The extraction of Li from the spent LiFePO4 cathode is enhanced by the selective removal using interactions between HCl and NaClO to dissolve the Li+ ion while Fe and P are retained in the structure. Several parameters, including the effects of dosage and drop acceleration of HCl and NaClO, reaction time, reaction temperature, and solid–liquid ratio on lithium leaching, were tested. The Total yields of lithium can achieve 97% after extraction process that lithium is extracted from the precipitated mother liquor, using an appropriate extraction agent that is a mixture of P507 and TBP and NF. The method also significantly reduced the use of acid and alkali, and the economic benefit of recycling is improved. Changes in composition, morphology, and structure of the material in the dissolution process are characterized by inductively coupled plasma optical emission spectrometry, scanning electron microscope, X-ray diffraction, particle size distribution instrument, and moisture analysis.

scholarly journals Solar-blind ultraviolet photodetector based on vertically aligned single-crystalline β-Ga2O3 nanowire arrays

Nanophotonics ◽  
2020 ◽  
Vol 9 (15) ◽  
pp. 4497-4503
Author(s):  
Liying Zhang ◽  
Xiangqian Xiu ◽  
Yuewen Li ◽  
Yuxia Zhu ◽  
Xuemei Hua ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Light Trapping ◽  
High Surface ◽  
Volume Ratio ◽  
Average Diameter ◽  
Nanowire Arrays ◽  
Etching Technique ◽  
Inductively Coupled ◽  
Solar Blind ◽  
Vertically Aligned

AbstractVertically aligned nanowire arrays, with high surface-to-volume ratio and efficient light-trapping absorption, have attracted much attention for photoelectric devices. In this paper, vertical β-Ga2O3 nanowire arrays with an average diameter/height of 110/450 nm have been fabricated by the inductively coupled plasma etching technique. Then a metal-semiconductor-metal structured solar-blind photodetector (PD) has been fabricated by depositing interdigital Ti/Au electrodes on the nanowire arrays. The fabricated β-Ga2O3 nanowire PD exhibits ∼10 times higher photocurrent and responsivity than the corresponding film PD. Moreover, it also possesses a high photocurrent to dark current ratio (Ilight/Idark) of ∼104 and a ultraviolet/visible rejection ratio (R260 nm/R400 nm) of 3.5 × 103 along with millisecond-level photoresponse times.

Manufacture of High Aspect Ratio Bulk Titanium Micro-Parts by Inductively Coupled Plasma Etching

2008 ◽  
Author(s):  
Gang Zhao ◽  
Qiong Shu ◽  
Yue Li ◽  
Jing Chen
Keyword(s):  
Aspect Ratio ◽  
High Aspect Ratio ◽  
Inductively Coupled Plasma ◽  
Etching Rate ◽  
Sidewall Roughness ◽  
Inductively Coupled ◽  
Icp Etching ◽  
Novel Technology ◽  
Micro Parts ◽  
Etching Mask

A novel technology is developed to fabricate high aspect ratio bulk titanium micro-parts by inductively coupled plasma (ICP) etching. An optimized etching rate of 0.9 μm/min has been achieved with an aspect ratio higher than 10:1. For the first time, SU-8 is used as titanium etching mask instead of the traditional hard mask such as TiO2 or SiO2. With an effective selectivity of 3 and a spun-on thickness beyond 100 μm, vertical etching sidewall and low sidewall roughness are obtained. Ultra-deep titanium etching up to 200 μm has been realized, which is among the best of the present reports. Titanium micro-springs and planks are successfully fabricated with this approach.

The Characteristic Evaluation of Hydroxyapatite Powders Synthesized from CaCO3 Refined from Oyster Shell and H3PO4

2006 ◽  
Vol 118 ◽  
pp. 639-644
Author(s):  
Hye Sung Kim ◽  
Su Chak Ryu
Keyword(s):  
Bone Density ◽  
Inductively Coupled Plasma ◽  
Oyster Shell ◽  
Atomic Emission ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Inductively Coupled ◽  
Infra Red ◽  
Ft Ir

Hydroxyapatite (Ca10(PO4)6(OH)2, HAp) powders is synthesized using the mixed powders of CaCO3 refined from oyster shells and phosphoric acid (H3PO4-98%, Daejung) as starting materials. The characteristic evaluation and chemical analysis of the synthesized powders is performed by X-ray diffraction (XRD), Fourier-transformed infra-red spectroscopy (FT-IR), and inductively-coupled plasma atomic emission spectroscopy (ICPAES). XRD analysis of synthetic powder by heat treatment at 1300°C for 2hrs shows only HAp peaks corresponding to stoichiometric HAp. It is confirmed by ICP-AES test that impurities such as Zn, In, Ti, Ba, Cd, Pb, and Mn, is not detected at all, but small amounts of Ti and Be is observed (0.099ppm Ti and 0.002ppm Ba). Variation of bone density is measured by giving medication of HAp powder with drinking water into human body continuously for three month. After the medication, the bone density is higher than the medication before. This means that HAp powder made from this process can be used as improver of bone density.

scholarly journals Characterization of Fly Ash Generated from Matla Power Station in Mpumalanga, South Africa

2012 ◽  
Vol 9 (4) ◽  
pp. 1788-1795 ◽  
Author(s):  
Olushola S. Ayanda ◽  
Olalekan S. Fatoki ◽  
Folahan A. Adekola ◽  
Bhekumusa J. Ximba
Keyword(s):  
Fly Ash ◽  
Inductively Coupled Plasma ◽  
Coal Fly Ash ◽  
Harmful Effect ◽  
Point Of Zero Charge ◽  
X Ray Diffraction ◽  
Power Station ◽  
X Ray ◽  
Inductively Coupled ◽  
Plasma Mass Spectrometry

In this study, fly ash was obtained from Matla power station and the physicochemical properties investigated. The fly ash was characterized by x-ray fluorescence, x-ray diffraction, scanning electron microscopy, and inductively coupled plasma mass spectrometry. Surface area, particle size, ash and carbon contents, pH, and point of zero charge were also measured. The results showed that the fly ash is alkaline and consists mainly of mullite (Al6Si2O13) and quartz (SiO2). Highly toxic metals As, Sb, Cd, Cr, and Pb as well as metals that are essential to health in trace amounts were also present. The storage and disposal of coal fly ash can thus lead to the release of leached metals into soils, surface and ground waters, find way into the ecological systems and then cause harmful effect to man and its environments.

scholarly journals Preliminary Archaeopetrological Study of the Lithic Industry From the l’Hort de la Boquera Rock Shelter (Margalef de Montsant, Tarragona, Spain): Applying Mineralogical and Geochemical Techniques

2018 ◽  
Vol 56 ◽  
pp. 23-33
Author(s):  
Mar Rey-Solé ◽  
Maria Pilar García-Argüelles ◽  
Jordi Nadal ◽  
Xavier Mangado ◽  
Anders Scherstén ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Raw Materials ◽  
Raw Material ◽  
Stone Tool ◽  
Petrographic Analysis ◽  
X Ray Diffraction ◽  
Inductively Coupled ◽  
Study Results ◽  
Lithic Industry ◽  
Plasma Mass Spectrometry

The l’Hort de la Boquera site is located in the northeastern part of Iberia and its stone tool assemblage includes up to 25,000 flint artefacts. This is the first approach to the analysis of the raw material through an archaeopetrological study. Results were obtained by use of mineralogi¬cal techniques: macroscopic and petrographic analysis, Scanning Electronic Microscopy (SEM), Micro-Raman and X-Ray diffraction (XRD); additionally, Laser Ablation Inductively Coupled Plasma Mass Spectrometry was applied. It has been possible to discriminate at least four flint categories, the ‘Evaporitic flint type’ (with two local subvarieties – ‘Common evaporitic’ and ‘Garnet’ varieties) that comes from local outcrops of the Ulldemolins Complex, and two flint types that had their origin further afield: the ‘Charophyta flint type’ (coming from the Torrente de Cinca Unit) and the ‘Dark flint type’ (from the La Serra Llarga Formation).These results make this study the most comprehensive analysis of raw materials that has been carried out in the area so far

scholarly journals A study concerning the pretreatment of CNTs and its influence on the performance of NIB/CNTs amorphous catalyst

2006 ◽  
Vol 71 (11) ◽  
pp. 1153-1160 ◽  
Author(s):  
Chang Hu-Yuan ◽  
Feng Li ◽  
Li. Hua ◽  
Bin Zhang
Keyword(s):  
Selective Hydrogenation ◽  
Inductively Coupled Plasma ◽  
Acid Treatment ◽  
Chemical Reduction ◽  
X Ray Diffraction ◽  
Chemical Reduction Method ◽  
X Ray ◽  
Inductively Coupled ◽  
Selective Hydrogenation Of Acetylene ◽  
Transmission Electron

As prepared carbon nanotubes were pretreated with nitric acid (CNTs-HNO3) or ammonia (CNTs-NH3). Fourier transform infrared spectroscopy (FTIR) measurements showed that the surface of the nanotubes was functionalized with carboxylic and hydroxyl functional groups after the acid treatment and that basic groups containing nitrogen, such as N-H and C-N, were introduced to the surface of the nanotubes after the ammonia treatment. X-Ray diffraction analysis implied that the nickel residue in the CNTs was effectively removed by acid treatment. However, the nickel residue was only partially eliminated by ammonia pretreatment. NiB amorphous catalysts supported on CNTs-HNO3 and CNTs-NH3 were prepared by the impregnation-chemical reduction method and characterized by transmission electron microscopy (TEM), as well as inductively coupled plasma (ICP) spectroscopy and studied in the selective hydrogenation of acetylene. TEM measurements showed that a high density NiB particles of about 9 nm were homogeneously dispersed on the CNTs-NH3. However, NiB particles (13-23 nm)with amean size of 16 nm were scattered on the CNTs-HNO3.As a result, the activity and selectivity of NiB/CNTs-NH3 were higher than those of NiB/CNTs-HNO3 in the selective hydrogenation of acetylene.

Comparing the Physico-Chemical Characteristics of Formulated and Marketed Yashada Bhasma

2021 ◽  
pp. 6392-6398
Author(s):  
Nitu Bhatnagar ◽  
Avani Pareek
Keyword(s):  
Inductively Coupled Plasma ◽  
Thermo Gravimetric Analysis ◽  
Human Consumption ◽  
Chemical Characteristics ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Inductively Coupled ◽  
Physico Chemical ◽  
The Difference

The present study is aimed to observe the difference in the Physico-Chemical characteristics of the marketed and formulated bhasma samples through X-Ray Diffraction analysis (XRD), Dynamic Light Scattering (DLS), Zeta potential, Thermo-Gravimetric analysis (TGA), Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray analysis (EDAX), apart from organoleptic methods. Inductively Coupled Plasma Mass Spectroscopy (ICPMS) analysis was also done to observe the presence of trace and heavy metals so that the safety of all these samples could be ensured. XRD shows variation in oxide nature of zinc as well crystallite size in all bhasma samples. DLS and SEM results show difference in particle size of marketed bhasma samples as compared to formulated Yashada bhasma. EDAX and ICPMS also confirm the alteration in elemental composition of all these bhasma samples. Thus, it can be concluded that these ayurvedic medicines should be prepared strictly using the formulation methods as mentioned in the Ayurvedic texts. This will help the prepared products to adopt the inherent quality of the ancient system of medicine, which shall be useful and devoid of any side effects for human consumption.

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