Electromigration in Al/W and Al(Cu)/W Interconnect Structures

1991 ◽  
Vol 225 ◽  
Author(s):  
C-K. Hu ◽  
P. S. Ho ◽  
M. B. Small ◽  
K. Kelleher
Keyword(s):  
Electron Microscope ◽  
Steady State ◽  
Scanning Electron Microscope ◽  
Drift Velocity ◽  
Current Density ◽  
Electron Microprobe ◽  
Temperature Range ◽  
Final Steady State ◽  
Current Densities ◽  
Scanning Electron

ABSTRACTThe electromigration drift velocity of Al in Al(3wt.% Si), Al(2wt.%Cu), and Al(2wt.%Cu,3wt.%Si) was measured in a temperature range 133 to 220 °C with current densities of 1.0 to 1.5×106A/cm2. In Al(3wt.% Si), a significant Al depletion at the cathode end and accumulation at the anode end of stripe were observed within a few hours at 1.5×106A/cm2 and 200°C. In addition, local hillocks and voids along the metal lines were observed. For Al(Cu,Si), the Al drift velocity was slowed down by Cu addition. The majority of hillocks started to grow at a distance about 6 μm away from the cathode end with current density of 1.5×106 A/cm2. The drift velocity of Al in Al(Cu,Si) was found to be a function of time starting with an initial low value and increasing to a an final steady-state value. The behavior was attributed to the migration of Cu and dissolution of Al2Cu precipitates. The activation energies of the depletion 3 Aμm of Al(2%,Cu, 3%Si) was determined to be 0.90±02 eV. The dissolution and growth of A12Cu in the tested samples of Ti/Al(2%Cu)/Ti/TiN were observed using the scanning electron microscope and an electron microprobe.

scholarly journals Morphology and ecology of Thalassiosira Cleve (Bacillariophyta) species rarely recorded in Brazilian coastal waters

2009 ◽  
Vol 69 (4) ◽  
pp. 1059-1071 ◽  
Author(s):  
M. Garcia ◽  
C. Odebrecht
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Water Temperature ◽  
Wide Temperature Range ◽  
Coastal Waters ◽  
Light Microscope ◽  
Temperature Range ◽  
The World ◽  
First Time ◽  
Scanning Electron

The detailed description of rarely recorded Thalassiosira species in Brazil is presented with light microscope (LM) and scanning electron microscope (SEM) illustrations. A total of 78 phytoplankton net samples (20 µm) collected between the years 2000 and 2006 in coastal waters of southern Brazilian, Cassino Beach and the estuary of Lagoa dos Patos, were studied in cleaned material using the Axiovert Zeiss LM and Jeol 6060 SEM. Water temperature and salinity of samples and six species are presented: Thalassiosira endoseriata, T. hendeyi, T. lundiana, T. minuscula, T. oceanica and T. wongii. Two species, Thalassiosira hendeyi and T. endoseriata were the most common being observed in all seasons at Cassino Beach in a wide temperature range (10-26 ºC), while only sporadically in the estuary of Lagoa dos Patos. Thalassiosira endoseriata, T. lundiana, T. oceanica and T. wongii are for the first time reported in Brazilian coastal waters. The latter two species, rarely recorded in the world, are fully illustrated based on Brazilian material.

Characteristics of Hot Ductility and Fracture in Micro-Alloyed Q345B Structural Steel

2011 ◽  
Vol 194-196 ◽  
pp. 150-156 ◽  
Author(s):  
Fang Dong ◽  
Cheng Su ◽  
Yuan Yuan Bai
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Continuous Casting ◽  
Structural Steel ◽  
Void Nucleation ◽  
Hot Ductility ◽  
Strain Rates ◽  
Casting Condition ◽  
Temperature Range ◽  
Scanning Electron

Hot-ductility tests of the microalloyed Q345B structural steel were performed in a tensile machine of Gleeble-1500D at different strain rates of 1.5•10-3/s 、2.5•10-3/s and 2•10-2/s and at temperature range from 1300°C to 700°C(Δ T=100°C ), which are close to the continuous casting condition of steel. Fracture surfaces were examined using a scanning electron microscope; it was found that the hot decrease as strain rate decrease, because the void growth mechanism predominates over void nucleation, giving time for nucleation cracks to grow. The minimum ductility was found at about 800°C for the strain rates of 1.5•10-3/s and 2.5•10-3/s, and the fracture was intergranular. The steel has good plasticity in temperature range from 1200°C to 900°C which is suitable for straighten operation.

Réactivités aux alcalis du grès de Potsdam dans les bétons

1977 ◽  
Vol 4 (3) ◽  
pp. 332-344 ◽  
Author(s):  
J. Berard ◽  
N. Lapierre
Keyword(s):  
New York ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Silica Gel ◽  
Electron Microprobe ◽  
Rock Type ◽  
Secondary Minerals ◽  
Alkali Silica Reactivity ◽  
External Sources ◽  
Scanning Electron

Numerous old concrete structures showing signs of disintegration are found in the Beauharnois–Valleyfield area located to the southwest of Montreal.After a short examination of some of the structures, evidences of alkali–silica reactivity appear to be related to sandstone aggregates belonging to the Potsdam group. This rock type, although common in the state of New York and in the provinces of Quebec and Ontario, is only very rarely used as an aggregate owing to its hardness and abrasion. Nevertheless, when available from important excavation sites it has sometimes been used as an aggregate with ordinary alkali-rich cements.The products of the chemical reactions between the siliceous aggregates and the cement were studied with a polarizing microscope, a scanning electron microscope, an electron microprobe, and a thermobalance and differential thermoanalyser.During these studies superposed layers of silica gel of variable composition were found and secondary minerals were also identified. The Na/K ratio was found to increase in the more recent layers of silica gel suggesting that sodium could have been added within the structures as winter de-icing salts.The hypothesis is put forward that even if a low alkali cement is used with this Potsdam sandstone, alkali–silica reactivity could still occur in the presence of alkalies from external sources.

Segregation and Precipitation Behavior of Phosphorus in a Ni-Fe-Cr Base Wrought Superalloy

2018 ◽  
Vol 913 ◽  
pp. 150-156 ◽  
Author(s):  
Sha Zhang ◽  
An Wen Zhang ◽  
Wei Yang Wang ◽  
Xin Xin ◽  
Kai Zhang
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Grain Boundaries ◽  
Energy Dispersive Spectroscopy ◽  
Peak Temperature ◽  
Energy Dispersive ◽  
Precipitation Behavior ◽  
Temperature Range ◽  
Precipitation Temperature ◽  
Scanning Electron

The segregation and precipitation behavior of phosphoruswas studied in aNi-Fe-Cr base wroughtsuperalloy. The precipitation behavior of phosphides in the alloy contained 0.025% Pwas examined after soaking at 750-1080°C to determine the precipitation temperature range of MNP-type phosphide. The microstructuresunder these various conditions wereinvestigated by scanning electron microscope(SEM) and energy dispersive spectroscopy (EDS). The precipitation temperature of the phosphide in the alloy was determined to be in the range of 850-1040 °C and the precipitation peak temperature was around 980°C.In addition, the melting temperatureof the phosphide was determined to be between 1200 °C and 1250 °C. The current results indicate the tendency of phosphorus segregated at grain boundaries.

New Instrumental Techniques and Their Application to Electron Microprobe Analysis and Scanning Electron Microscopy

1970 ◽  
Vol 24 (4) ◽  
pp. 420-426 ◽  
Author(s):  
James P. Smith ◽  
Lee R. Reid
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Electron Microprobe ◽  
Secondary Electron Emission ◽  
Rate Analysis ◽  
Quantitative Measurements ◽  
Modulation Techniques ◽  
New Instrumentation ◽  
Phase Sensitive ◽  
Scanning Electron

This paper reviews several applications of new instrumentation which have been developed for the electron microprobe analyzer and the scanning electron microscope. By using signal modulation techniques and phase sensitive detection, the information from the scanning electron microscope is made more quantitative. Digital techniques applied to photomultiplier outputs allow more sensitive and quantitative measurements of cathodoluminescence intensities and secondary electron emission. The technique of pulse rate analysis is used to enhance the information contained in x-ray scanning micrographs from an electron microprobe analyzer. Several examples of these techniques are discussed.

Metallography and Corrosion Product Studies on Archaeological Bronze Fragments from the Qu Cun Site

1996 ◽  
Vol 462 ◽  
Author(s):  
W. T. Chase ◽  
Quanyu Wang
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Corrosion Product ◽  
Electron Microprobe ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heat Treated ◽  
Western Zhou ◽  
Future Work ◽  
Scanning Electron

ABSTRACTThe authors studied a suite of fragments of corroded bronzes from the Tienma-Qu Cun site, a Western Zhou city and cemetery complex dating from ca. 1000 to ca. 650 B.C‥ Conventional metallographic techniques were used along with scanning electron microscope, electron microprobe and x-ray diffraction. The bronzes are very varied in structure and composition. Most are cast, moderate-tin bronzes, but some are high or low in tin or lead. A few show a worked and annealed structure, and some of the cast bronzes were also heat treated (possibly by use as cooking pots). corrosion patterns also vary greatly, from almost uncorroded to total mineralization. Periodic and esquential corrosion phenomena were detected, as well as patination applied when the bronzes were made. We had hoped to be able to ascertain the causes of the different penetration of corrosion in these samples, but that must remain for future work.

Electron Microprobe and Scanning Electron Microscope Investigations on Plate-Shaped CdS Single Crystals

1968 ◽  
Vol 29 (2) ◽  
pp. K89-K90
Author(s):  
P. Flögel ◽  
E. Nebauer ◽  
H.-J. Ullrich ◽  
S. Däbritz ◽  
F. Zimmer
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Single Crystals ◽  
Electron Microprobe ◽  
Scanning Electron
Sign in / Sign up

Export Citation Format

Share Document