The Strength of High-Temperature Ag–In Joints Produced Between Copper by Fluxless Low-Temperature Processes

2014 ◽  
Vol 136 (1) ◽  
Author(s):  
Yuan-Yun Wu ◽  
Chin C. Lee
Keyword(s):  
Solid Solution ◽  
Electron Microscope ◽  
Shear Test ◽  
Test Results ◽  
X Ray ◽  
Ductile Mode ◽  
Micron Size ◽  
Cu Substrates ◽  
Strength And Ductility ◽  
Scanning Electron

Two copper (Cu) substrates were bonded using silver (Ag) and indium (In) and annealed at 200–250 °C to convert the joints into the solid solution (Ag) for enhanced strength and ductility. Cu–Cu pair was chosen so that the samples break in the joint during shear test. The upper Cu was electroplated with 15 μm Ag. The lower Cu was plated with 15 μm Ag, followed by In and 0.1 μm Ag to inhibit indium oxidation. Two designs were implemented, using 8 μm and 5 μm In, respectively. The Cu substrates were bonded at 180 °C in 100 mTorr vacuum without flux. Afterwards, samples were annealed at 200 °C for 1000 h (first design) and at 250 °C for 350 h (second design), respectively. Scanning electron microscope with energy dispersive X-ray analysis (SEM and EDX) results indicate that the joint of the first design is an alloy of mostly (Ag) with micron-size Ag2In and (ζ) regions, and that of second design has converted to a single (Ag) phase. Shear test results show that the samples are very strong. The breaking forces far exceed requirements in MIL-STD-883 H standards. Fracture incurs inside the joint and is a mix of brittle and ductile modes or only ductile mode. The joint solidus temperatures are 600 °C and 900 °C for the first and second designs, respectively.

Validation of the expert methodology «Detection of condensed traces of the gunshot residue containing heavy metal compounds on various objects by scanning electron microscopy and X-ray microanalysis»

2021 ◽  
Vol 87 (12) ◽  
pp. 63-72
Author(s):  
S. A. Smirnova ◽  
I. B. Afanasyev ◽  
G. I. Bebeshko ◽  
G. G. Omel’yanyuk
Keyword(s):  
Electron Microscopy ◽  
Heavy Metal ◽  
Scanning Electron Microscopy ◽  
Electron Microscope ◽  
Standard Sample ◽  
Gunshot Residue ◽  
Test Results ◽  
Metal Compounds ◽  
X Ray ◽  
Scanning Electron

We present and discuss the results of the validation of a forensic qualitative testing technique which consists in the detection of condensed traces of the gunshot residue (GSR) in the form of individual microparticles on the objects under study and their identification by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) using a scanning electron microscope Mira III (Tescan, Czech Republic) equipped with a system of X-ray microanalysis INCA GSR 450 (Oxford Nanoanalysis, Great Britain). The procedure for detecting GSR particles containing heavy metal compounds, systems of their classification and interpretation of test results are described. The suitability of the methodology for solving forensic problems has been confirmed. The validation procedure consists in assessing the reliability by comparing the test results obtained by experts (A and B) in two laboratories at different times using the same device, and in confirming the competence of experts proceeding from the results of blind tests. A standard sample ENFSI GSR PT 2018 A-03-07 is used. Each of the experts determined the number of particles classified as GSR present in control samples taken in a ballistic laboratory during a full-scale experiment: from the hands of the shooter; from the hands of a person who did not shoot; without microparticles (clean stage of an electron microscope). The reliability of the technique is characterized by the index (probability) of correct results of detecting GSR particles in the standard sample of at least 95.8% and by a small proportion of false results (no more than 5.4%). The competence of the experts is proved by the consistent results of «blind» testing of control full-scale samples, containing and not containing GSR particles obtained in different laboratories. The results of the validation indicate the suitability of the method for obtaining reliable and valid information about the presence of GSR particles on the objects under study.

Phases Evolution and Y Solid Solution Microstructure in the Mg-6Zn-3Y Alloy Solidified under Super-High Pressure

2011 ◽  
Vol 148-149 ◽  
pp. 1347-1350
Author(s):  
Yun Dong ◽  
Xiao Ping Lin ◽  
Run Guo Zheng ◽  
Shi Hui Jiao
Keyword(s):  
Solid Solution ◽  
High Pressure ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Dendritic Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Matrix ◽  
Solidification Pressure ◽  
Scanning Electron

The solidification microstructure of Mg-6Zn-3Y alloy under super-high pressure was investigated by using X-ray diffraction (XRD) and scanning electron microscope (SEM). The results show that the dendritic structure of Mg-6Zn-3Y alloy under super-high pressure (GPa level) can be evidently refined with the increase of solidification pressure. When the pressure increases to 2 GPa, Y element can’t solubilize in matrix of a-Mg, the primary Y solid solution is distributed in the shape of polygon block in the matrix. When the pressure is up to 4 GPa, the primary Y solid solution appears as symmetrical petaline shape. So Y solid solution exhibits the different morphology with the change of the pressure

The Existence Form and Distribution of Mn in Production of Tungsten Products

2014 ◽  
Vol 628 ◽  
pp. 33-39
Author(s):  
Ya Lei Li ◽  
Dun Qiang Tan ◽  
Xin Yang ◽  
Wen He ◽  
Hong Bo Zhu ◽  
...  
Keyword(s):  
Solid Solution ◽  
Electron Microscope ◽  
Reduction Process ◽  
X Ray Diffraction ◽  
Powder Morphology ◽  
Low Contrast ◽  
X Ray ◽  
Transmission Electron ◽  
Different Content ◽  
Scanning Electron

The effect of doping different content of Mn into ammonium paratungstate (APT) on the production of tungsten products was studied systematically. The calcination of APT, reduction of WO3 and carbonization of W were studied in sequence.The phase composition, powder morphology, existence form and distribution of Mn were analyzed by X-ray diffraction, scanning electron microscope and transmission electron microscope, respectively. The results showed that Mn converted from MnCl2 to Mn2+WO4 during reduction process. And then Mn2+WO4 converted to Mn5C2 in the process of carbonization. Besides, Mn finally existed as the form of (Mn, W) C solid solution and Mn5C2. The distribution of Mn was always in the low contrast areas.

Reaction Synthesis of (Ti,Cr) 2AlC/Al2O3 In Situ Solid Solution Composite

2011 ◽  
Vol 480-481 ◽  
pp. 519-522
Author(s):  
Jian Feng Zhu ◽  
Na Han
Keyword(s):  
Solid Solution ◽  
Electron Microscope ◽  
Reaction Mechanism ◽  
Melting Point ◽  
Intermetallic Compound ◽  
Phase Evolution ◽  
Reaction Synthesis ◽  
X Ray ◽  
Scanning Electron

The (Ti,Cr)2AlC/Al2O3 solid solution composite has been synthesized by in situ aluminothermic reduction of the blend powders of Ti, Al, Cr2O3 and carbon black. The phase evolution during the formation of the composite was examined at the temperatures from 700 °C to 1400 °C. Based on the results of X-ray diffractometry (XRD) and differential scanning calorimeter (DSC), a possible reaction mechanism was brought forward to explain the formation of (Ti,Cr)2AlC/Al2O3 solid solution composite. Above the melting point of aluminum, liquid Al reacted with titanium to form the intermetallic compound of TiAl. As the temperature increased to 900 °C, the intermetallic compound of TiAl reacted with TiC to form Ti2AlC. The microstructures of the as prepared samples were also analyzed by the scanning electron microscope (SEM) together with the election dispersive spectroscopy (EDS).

Reaction Synthesis of (Ti,V)2AlC/Al2O3 Composite

2011 ◽  
Vol 230-232 ◽  
pp. 1274-1277
Author(s):  
Jian Feng Zhu ◽  
Na Han
Keyword(s):  
Solid Solution ◽  
Electron Microscope ◽  
Reaction Mechanism ◽  
Melting Point ◽  
Intermetallic Compound ◽  
Phase Evolution ◽  
Reaction Synthesis ◽  
X Ray ◽  
Scanning Electron

The (Ti,V)2AlC/Al2O3 solid solution composite has been synthesized by in situ aluminothermic reduction of the blend powders of Ti, Al, V2O5 and active carbon. The phase evolution during the formation of the composite was examined at the temperature from 500 °C to 1400 °C. Based on the results of X-ray diffractometry (XRD) and differential scanning calorimeter (DSC), a possible reaction mechanism was proposed to explain the formation of (Ti,V)2AlC/Al2O3 solid solution composite. Above the melting point of aluminum, liquid Al reacted with titanium to form the intermetallic compound of TiAl. As the temperature increased to 1300 °C, the intermetallic compound of TiAl reacted with TiC to form Ti2AlC. The microstructures of the as prepared samples were also analyzed by the scanning electron microscope (SEM) together with the election dispersive spectroscopy (EDS).

X-ray micro tomography in the scanning electron microscope

1978 ◽  
Vol 36 (1) ◽  
pp. 106-107 ◽  
Author(s):  
W. Brünger
Keyword(s):  
Electron Beam ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Target Surface ◽  
The Body ◽  
X Rays ◽  
Cross Sectional ◽  
X Ray ◽  
Micro Tomography ◽  
Scanning Electron

Reconstructive tomography is a new technique in diagnostic radiology for imaging cross-sectional planes of the human body /1/. A collimated beam of X-rays is scanned through a thin slice of the body and the transmitted intensity is recorded by a detector giving a linear shadow graph or projection (see fig. 1). Many of these projections at different angles are used to reconstruct the body-layer, usually with the aid of a computer. The picture element size of present tomographic scanners is approximately 1.1 mm2.Micro tomography can be realized using the very fine X-ray source generated by the focused electron beam of a scanning electron microscope (see fig. 2). The translation of the X-ray source is done by a line scan of the electron beam on a polished target surface /2/. Projections at different angles are produced by rotating the object.During the registration of a single scan the electron beam is deflected in one direction only, while both deflections are operating in the display tube.

PHAX-SCAN: Functional integration of a Scanning Electron Microscope and an energy-dispersive x-ray analyser

1989 ◽  
Vol 47 ◽  
pp. 56-57
Author(s):  
Marc H. Peeters ◽  
Max T. Otten
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
High Speed ◽  
High Performance ◽  
Functional Integration ◽  
Energy Dispersive ◽  
X Rays ◽  
X Ray ◽  
High Speed Analysis ◽  
Scanning Electron

Over the past decades, the combination of energy-dispersive analysis of X-rays and scanning electron microscopy has proved to be a powerful tool for fast and reliable elemental characterization of a large variety of specimens. The technique has evolved rapidly from a purely qualitative characterization method to a reliable quantitative way of analysis. In the last 5 years, an increasing need for automation is observed, whereby energy-dispersive analysers control the beam and stage movement of the scanning electron microscope in order to collect digital X-ray images and perform unattended point analysis over multiple locations.The Philips High-speed Analysis of X-rays system (PHAX-Scan) makes use of the high performance dual-processor structure of the EDAX PV9900 analyser and the databus structure of the Philips series 500 scanning electron microscope to provide a highly automated, user-friendly and extremely fast microanalysis system. The software that runs on the hardware described above was specifically designed to provide the ultimate attainable speed on the system.

PENGGUNAAN TiO2 PARTIKEL NANO HASIL SINTESIS BERBASIS AIR MENGGUNAKAN METODA SOL-GEL PADA BAHAN KAPAS SEBAGAI APLIKASI UNTUK TEKSTIL ANTI UV

Arena Tekstil ◽  
2013 ◽  
Vol 28 (1) ◽  
Author(s):  
Maya Komalasari ◽  
Bambang Sunendar
Keyword(s):  
Fourier Transform ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Sol Gel ◽  
Crosslinking Agent ◽  
X Ray Diffraction ◽  
Nano Tio2 ◽  
X Ray ◽  
Infra Red ◽  
Scanning Electron

Partikel nano TiO2 berbasis air dengan pH basa telah berhasil disintesis dengan menggunakan metode sol-gel dan diimobilisasi pada kain kapas dengan menggunakan kitosan sebagai zat pengikat silang. Sintesis dilakukan  dengan prekursor TiCl4 pada konsentrasi 0,3 M, 0,5 M dan 1 M, dan menggunakan templat kanji dengan proses kalsinasi pada suhu 500˚C selama 2 jam. Partikel nano TiO2 diaplikasikan ke kain kapas dengan metoda pad-dry-cure dan menggunakan kitosan sebagai crosslinking agent. Berdasarkan hasil Scanning Electron Microscope (SEM),diketahui bahwa morfologi partikel TiO2 berbentuk spherical dengan ukuran nano (kurang dari 100 nm). Karakterisasi X-Ray Diffraction (XRD) menunjukkan adanya tiga tipe struktur kristal utama, yaitu (100), (101) dan (102) dengan fasa kristal yang terbentuk adalah anatase dan rutile. Pada karakterisasi menggunakan SEM terhadap serbuk dari TiO2 yang telah diaplikasikan ke permukaan kain kapas, terlihat adanya imobilisasi partikel nano TiO2 melalui ikatan hidrogen silang dengan kitosan pada kain kapas. Hasil analisa tersebut kemudian dikonfirmasi dengan FTIR (Fourier Transform Infra Red) yang hasilnya memperlihatkan puncak serapan pada bilangan gelombang 3495 cm-1, 2546 cm-1, dan 511 cm-1,  yang masing-masing diasumsikan sebagai adanya vibrasi gugus fungsi O-H, N-H dan Ti-O-Ti. Hasil SEM menunjukkan pula bahwa kristal nano yang terbentuk diantaranya adalah fasa rutile , yang berdasarkan literatur terbukti dapatberfungsi sebagai anti UV.

Failure Analysis of Killer Defects and Yield Enhancement of Flat ROM Devices in Wafer Fabrication

2000 ◽  
Author(s):  
Y. N. Hua ◽  
Z. R. Guo ◽  
L. H. An ◽  
Shailesh Redkar
Keyword(s):  
Electron Microscope ◽  
Failure Analysis ◽  
Fault Isolation ◽  
Yield Enhancement ◽  
Wafer Fabrication ◽  
X Ray ◽  
Particle Contamination ◽  
Emission Microscopy ◽  
Microscopy Techniques ◽  
Scanning Electron

Abstract In this paper, some low yield cases in Flat ROM device (0.45 and 0.6 µm) were investigated. To find killer defects and particle contamination, KLA, bitmap and emission microscopy techniques were used in fault isolation. Reactive ion etching (RIE) and chemical delayering, 155 Wright Etch, BN+ Etch and scanning electron microscope (SEM) were used for identification and inspection of defects. In addition, energy-dispersive X-ray microanalysis (EDX) was used to determine the composition of the particle or contamination. During failure analysis, seven kinds of killer defects and three killer particles were found in Flat ROM devices. The possible root causes, mechanisms and elimination solutions of these killer defects/particles were also discussed.

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