Mechanical Interlocking on Leadframe Surface for Bondability of Au Wedge Bond

2016 ◽  
Vol 857 ◽  
pp. 79-82
Author(s):  
Roslina Ismail ◽  
Fuaida Harun ◽  
Azman Jalar ◽  
Shahrum Abdullah
Keyword(s):  
Optical Microscope ◽  
Bonding Process ◽  
Mechanical Interlocking ◽  
Average Roughness ◽  
Force Microscopy ◽  
Atomic Force ◽  
Surface Morphologies ◽  
Scanning Electron ◽  
Effect Of Surface

This work is a contribution towards the understanding of wire bond integrity and reliability in relation to their microstructural and mechanical properties in semiconductor packaging.The effect of surface roughness and hardness of leadframe on the bondability of Au wedge bond still requires detail analysis. Two type of leadframes namely leadframe A and leadframe B were chosen and scanning electron microscope (SEM) and optical microscope were used to inspect the surface morphology of leadframes and the quality of created Au wedge bond after wire bonding process. It was found that there were significant differences in the surface morphologies between these two leadframes. The atomic force microscopy (AFM) which was utilized to measure the average roughness, Ra of lead finger confirms that leadframe A has the highest Ra with value of 166.46 nm compared to that of leadframe B with value of 85.89 nm. While hardness value of different lead finger from the selected leadframe A and B obtained using Vicker microhardness tester are 180.9 VH and 154.2VH respectively.

scholarly journals Enhancment of the corrosion resistance of copper metal by laser surface treatment

2020 ◽  
Vol 18 (46) ◽  
pp. 13-19
Author(s):  
Lubna Abdul Razzaq Mosleh ◽  
Ahmed Qasim Abdullaa
Keyword(s):  
Corrosion Resistance ◽  
Surface Treatment ◽  
Optical Microscope ◽  
Laser Surface ◽  
Laser Surface Treatment ◽  
Copper Metal ◽  
Average Roughness ◽  
Force Microscopy ◽  
Atomic Force ◽  
Structure Properties

In this paper, the corrosion rate of copper is the seawater that has been studied after laser surface treatment with local energy 1 Joul to get to the surface melting. The application of laser surface treatment to improve the corrosion resistance of copper using electrochemical polarization. The surface morphology and structure properties have been studied using optical microscope (OM), Atomic force microscopy (AFM) and XRD, XRF. Besides macro-hardness. The results show that higher corrosion resistance, higher hardness and lower average roughness due to laser surface treatment.  

Homoepitaxial Growth and Characterization of 4H-SiC Epilayers by Low-Pressure Hot-Wall Chemical Vapor Deposition

2006 ◽  
Vol 527-529 ◽  
pp. 191-194 ◽  
Author(s):  
Guo Sheng Sun ◽  
Jin Ning ◽  
Quan Cheng Gong ◽  
Xin Gao ◽  
Lei Wang ◽  
...  
Keyword(s):  
Chemical Vapor ◽  
Low Pressure ◽  
Optical Microscope ◽  
Thick Sample ◽  
Force Microscopy ◽  
Homoepitaxial Growth ◽  
Atomic Force ◽  
Blocking Voltage ◽  
Gas System ◽  
Surface Morphologies

Horizontal air-cooled low-pressure hot-wall CVD (LP-HWCVD) system is developed to get high quality 4H-SiC epilayers. Homoepitaxial growth of 4H-SiC on off-oriented Si-face (0001) 4H-SiC substrates purchased from Cree is performed at a typical temperature of 1500°C with a pressure of 40 Torr by using SiH4+C2H4+H2 gas system. The surface morphologies and structural and optical properties of 4H-SiC epilayers are characterized with Nomarski optical microscope, atomic force microscopy (AFM), x-ray diffraction, Raman scattering, and low temperature photoluminescence (LTPL). The background doping of 32 μm-thick sample has been reduced to 2-5×1015 cm-3. The FWHM of the rocking curve is 9-16 arcsec. Intentional N-doped and B-doped 4H-SiC epilayers are obtained by in-situ doping of NH3 and B2H6, respectively. Schottky barrier diodes with reverse blocking voltage of over 1000 V are achieved preliminarily.

scholarly journals Amazonian tuber starch based films incorporated with silver nanoparticles for preservation of fruits

2021 ◽  
Vol 10 (6) ◽  
pp. e23510615304
Author(s):  
Larissa Svetlana Cavalcante Silva ◽  
Salomão Rocha Martim ◽  
Dib Mady Diniz Gomes ◽  
Fabiano Brito Prado ◽  
Nélly Mara Vinhote Marinho ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Water Vapor Permeability ◽  
Vapor Permeability ◽  
Microbiological Analysis ◽  
X Ray Diffraction ◽  
Natural Polymers ◽  
Average Roughness ◽  
Force Microscopy ◽  
Atomic Force

Films and coatings based on natural polymers are used to conserve nutritional quality of fruits, vegetables and also delay their ripening. The purpose of this study was to develop films with starch extracted from Dioscorea altissima Lam. (dunguey) incorporated with silver nanoparticles for coating and preserving fruits. The films obtained by cast were characterized visually, by Scanning Electron Microscope, by Atomic Force Microscopy, by X-Ray Diffraction and by Fourier-Transform Infrared Spectroscopy. Antimicrobial activity and technological properties were also evaluated. The coating of camu-camu fruits [Myrciaria dubia (Kunth) McVaugh] was carried out by immersing them in the filmogenic solution, followed by their physicochemical and microbiological analysis. The films with silver nanoparticles showed transparency, flexibility, spherical clusters and a higher average roughness. A reduction in thickness, solubility and water vapor permeability was also observed. Antimicrobial action against Staphylococcus aureus and Escherichia coli was proved as well. The fruits coated with films exhibited delay in ripening, with maintenance of quality and longevity. Uncoated fruits showed greater wilting and wrinkling. The starch film incorporated with silver nanoparticles was effective for preserving camu-camu fruit.

Etching Treatment Effect on Surface Morphology of Dental Structures

2017 ◽  
Vol 68 (11) ◽  
pp. 2700-2703 ◽  
Author(s):  
Kamel Earar ◽  
Vasile Iulian Antoniac ◽  
Sorana Baciu ◽  
Simion Bran ◽  
Florin Onisor ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Surface Morphology ◽  
Phosphoric Acid ◽  
Human Teeth ◽  
Strong Bond ◽  
Force Microscopy ◽  
Atomic Force ◽  
Human Dentine ◽  
Dental Surface ◽  
Scanning Electron

This study examined and compared surface of human dentine after acidic etching with hydrogen peroxide, phosphoric acid liquid and gel. Surface demineralization of dentin is necessary for a strong bond of adhesive at dental surface. Split human teeth were used. After application of mentioned substances at dentin level measures of the contact angle and surface morphology were employed. Surface morphology was analyzed with the help of scanning electron microscopy and atomic force microscopy. Liquid phosphoric acid yielded highest demineralization showing better hydrophobicity than the rest, thus having more contact surface. Surface roughness are less evident and formed surface micropores of 4 �m remained open after wash and air dry providing better adhesive canalicular penetration and subsequent bond.

Structural and Optical Properties of InAsSbBi Grown by Molecular Beam Epitaxy on Offcut GaSb Substrates

Photonics ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 215
Author(s):  
Rajeev R. Kosireddy ◽  
Stephen T. Schaefer ◽  
Marko S. Milosavljevic ◽  
Shane R. Johnson
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Optical Quality ◽  
X Ray Diffraction ◽  
Interface Quality ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Lateral Variations

Three InAsSbBi samples are grown by molecular beam epitaxy at 400 °C on GaSb substrates with three different offcuts: (100) on-axis, (100) offcut 1° toward [011], and (100) offcut 4° toward [011]. The samples are investigated using X-ray diffraction, Nomarski optical microscopy, atomic force microscopy, transmission electron microscopy, and photoluminescence spectroscopy. The InAsSbBi layers are 210 nm thick, coherently strained, and show no observable defects. The substrate offcut is not observed to influence the structural and interface quality of the samples. Each sample exhibits small lateral variations in the Bi mole fraction, with the largest variation observed in the on-axis growth. Bismuth rich surface droplet features are observed on all samples. The surface droplets are isotropic on the on-axis sample and elongated along the [011¯] step edges on the 1° and 4° offcut samples. No significant change in optical quality with offcut angle is observed.

scholarly journals Corrosion Behavior and Mechanical Properties of a Nanocomposite Superhydrophobic Coating

Coatings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 652
Author(s):  
Divine Sebastian ◽  
Chun-Wei Yao ◽  
Lutfun Nipa ◽  
Ian Lian ◽  
Gary Twu
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Atomic Force Microscopy ◽  
Nanocomposite Coating ◽  
Superhydrophobic Coating ◽  
Force Microscopy ◽  
Atomic Force ◽  
Microscopy Images ◽  
Scanning Electron

In this work, a mechanically durable anticorrosion superhydrophobic coating is developed using a nanocomposite coating solution composed of silica nanoparticles and epoxy resin. The nanocomposite coating developed was tested for its superhydrophobic behavior using goniometry; surface morphology using scanning electron microscopy and atomic force microscopy; elemental composition using energy dispersive X-ray spectroscopy; corrosion resistance using atomic force microscopy; and potentiodynamic polarization measurements. The nanocomposite coating possesses hierarchical micro/nanostructures, according to the scanning electron microscopy images, and the presence of such structures was further confirmed by the atomic force microscopy images. The developed nanocomposite coating was found to be highly superhydrophobic as well as corrosion resistant, according to the results from static contact angle measurement and potentiodynamic polarization measurement, respectively. The abrasion resistance and mechanical durability of the nanocomposite coating were studied by abrasion tests, and the mechanical properties such as reduced modulus and Berkovich hardness were evaluated with the aid of nanoindentation tests.

Lateral Size of Self-Patterned Nanostructures Controlled by Multi-Step Deposition

2005 ◽  
Vol 106 ◽  
pp. 117-122 ◽  
Author(s):  
Izabela Szafraniak ◽  
Dietrich Hesse ◽  
Marin Alexe
Keyword(s):  
Electron Microscopy ◽  
Ultrathin Films ◽  
Lateral Size ◽  
X Ray Diffraction ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Non Volatile Memory ◽  
Ferroelectric Capacitors ◽  
Scanning Electron

Self-patterning presents an appealing alternative to lithography for the production of arrays of nanoscale ferroelectric capacitors for use in high density non-volatile memory devices. Recently a self-patterning method, based on the use of the instability of ultrathin films during hightemperature treatments, was used to fabricate nanosized ferroelectrics. This paper reports the use of the method for the preparation of PZT nanoislands on different single crystalline substrates - SrTiO3, MgO and LaAlO3. Moreover, a multi-step deposition procedure in order to control lateral the dimension of the crystals was introduced. The nanostructures obtained were studied by atomic force microscopy, scanning electron microscopy and X-ray diffraction.

Si+ Implantation and Activation in GaN Comparison of GaN on Sapphire and GaN on Silicon

2012 ◽  
Vol 711 ◽  
pp. 213-217 ◽  
Author(s):  
Anne Elisabeth Bazin ◽  
Frédéric Cayrel ◽  
Mohamed Lamhamdi ◽  
Arnaud Yvon ◽  
Jean Christophe Houdbert ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Ohmic Contacts ◽  
Silicon Oxide ◽  
Electrical Activation ◽  
Specific Contact Resistance ◽  
Force Microscopy ◽  
Atomic Force ◽  
Specific Contact ◽  
Good Behaviour ◽  
Scanning Electron

In this paper, we evaluated gallium nitride heteroepitaxially grown on sapphire (GaN/Sa) and grown on silicon (GaN/Si) faced to implantation doping. Si+ was implanted on low doped n-type epilayers in order to create a plateau around 1020at.cm-3. All the samples were capped with a silicon oxide and annealed between 1000°C and 1150°C. The surface quality was evaluated in terms of roughness, pit density and maximum pit diameter using Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). Finally, the dopant electrical activation was studied with Ti-Al contacts using the circular Transfert Length Method (c-TLM). This study shows that low Specific Contact Resistance (SCR) values of 8x10-5Ω.cm2 and 6x10-6Ω.cm2 are respectively obtained on GaN/Sa sample annealed at 1150°C-2min and on GaN/Si sample annealed at 1150°C-30s, proving that good ohmic contacts are obtained on both materials. Nevertheless, a compromise has to be done between the low SCR values obtained and the GaN surface degradation, observed by AFM and SEM after the different annealing treatments and which could affect the good behaviour of the GaN devices.

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