scholarly journals Depth profiling of degradation of multilayer photovoltaic backsheets after accelerated laboratory weathering: Cross-sectional Raman imaging

2016 ◽  
Vol 144 ◽  
pp. 289-299 ◽  
Author(s):  
Chiao-Chi Lin ◽  
Peter J. Krommenhoek ◽  
Stephanie S. Watson ◽  
Xiaohong Gu
Keyword(s):  
Depth Profiling ◽  
Raman Imaging ◽  
Cross Sectional

Confocal Raman imaging and chemometrics applied to solve forensic document examination involving crossed lines and obliteration cases by a depth profiling study

The Analyst ◽  
2017 ◽  
Vol 142 (7) ◽  
pp. 1106-1118 ◽  
Author(s):  
Flávia de Souza Lins Borba ◽  
Tariq Jawhari ◽  
Ricardo Saldanha Honorato ◽  
Anna de Juan
Keyword(s):  
Analytical Method ◽  
Depth Profiling ◽  
Raman Imaging ◽  
Confocal Raman ◽  
Document Examination ◽  
Non Destructive

This article describes a non-destructive analytical method developed to solve forensic document examination problems involving crossed lines and obliteration.

Analysis of 16 QFN Device I/O Pads for Solderability Failures

2015 ◽  
Vol 2015 (1) ◽  
pp. 000675-000684
Author(s):  
Rama Hegde ◽  
Anne Anderson ◽  
Sam Subramanian ◽  
Andrew Mawer ◽  
Ed Hall ◽  
...  
Keyword(s):  
Cross Section ◽  
Printed Circuit Board ◽  
Depth Profiling ◽  
Lessons Learned ◽  
Circuit Board ◽  
Physical Analysis ◽  
Lead Frame ◽  
Cross Sectional ◽  
Root Cause ◽  
Industry Standard

In-process failures were experienced during printed circuit board (PCB) SMT assembly of a 16 Quad Flat No Leads (QFN) device. The failures appeared to be solderability related with QFN unit I/O pads not soldering robustly and sometimes leading to QFN detachment following board mounting. When assembly did take place on affected QFN units, the resulting solder joint was observed to be weak. This paper reports on very systematic analyses of the QFN device I/O pads using optical inspections, AES surface, AES depth profiling, SEM/EDX, SIMS, FIB and TEM cross-sectional measurements to determine the root cause of the failure and the failure mechanism. The detached QFN units, suspect and good unsoldered units, passing and failing units obtained from customers were examined. The industry standard surface mount solderability testing was performed on good and suspect parts, and all were observed to pass as evidenced by >95% coverage of the I/O pads. Optical inspections and a wide variety of physical analysis of the pads on fresh parts showed no anomalies with only the expected Au over Pd over Ni found. AES analysis was performed including depth profiling to look for any issues in the NiPdAu over base Cu plating layers that could be contributing the solderability failures. The AES depth profiling indicated AuPd film on the Ni under layer for the I/O pads as expected. No unexpected elements or oxide layers were observed at any layer. Then, one failing and one passing units were compared by doing FIB cross-section, FIB planar section and TEM cross-section analysis. The cross-sectional analysis showed rough Ni surface for the failing units, while the Ni surface was relatively smooth for the passing unit. Further, finer Cu grains and Ni grains were observed on the passing units. Additionally, the lead frame fabrication process mapping showed rough Cu, Ni “texturing” and use of low electro chemical polishing (ECP) current on the bad units compared to that of the good units. All affected bad units were confirmed coming from a second source Cu supplier with the rough Cu. The weak and irregular NiSn IMC formation on the bad units caused IMC separation and possible spalling during board solder reflow primarily due to the rough base Cu and irregular grain sizes and resulting lower ECP lead frame plating current. A possible final factor was marginally low Pd thickness. In conclusion, the 16 QFN device solderability failure root cause summary and the lessons learned from a wide variety of analysis techniques will be discussed.

A Study of Nucleation and Growth in MOCVD: The Growth of Thin Films of Alumina

2000 ◽  
Vol 648 ◽  
Author(s):  
M.P. Singh ◽  
S. Mukhopadhayay ◽  
Anjana Devi ◽  
S.A. Shivashankar
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Secondary Ion Mass Spectrometry ◽  
Film Growth ◽  
Depth Profiling ◽  
Chemical Vapor ◽  
Nucleation And Growth ◽  
Cross Sectional ◽  
Alumina Films ◽  
Pressure Chemical

AbstractWe have studied the nucleation and growth of alumina by metalorganic chemical vapor deposition (MOCVD). The deposition of alumina films was carried out on Si(100) in a horizontal, hot-wall, low pressure chemical vapor deposition (CVD) reactor, using aluminum acetylacetonate{Al(acac)3}as the CVD precursor. We have investigated growth of alumina films as a function of different CVD parameters such as substrate temperature and total reactor pressure during film growth. Films were characterized by optical microscopy, X-ray diffractometry (XRD), scanning electron microscopy (SEM), cross-sectional SEM, and secondary ion mass spectrometry (SIMS) compositional depth profiling. The chemical analysis reveals that the carbon is present throughout the depth of the films.

Quantitative investigation of titanium/amorphous-silicon multilayer thin film reactions

1990 ◽  
Vol 5 (3) ◽  
pp. 593-600 ◽  
Author(s):  
R. R. De Avillez ◽  
L. A. Clevenger ◽  
C. V. Thompson ◽  
K. N. Tu
Keyword(s):  
Thin Film ◽  
Activation Energy ◽  
Amorphous Silicon ◽  
Depth Profiling ◽  
Multilayer Films ◽  
Heat Of Formation ◽  
Titanium Silicide ◽  
Scanning Calorimetry ◽  
Cross Sectional ◽  
Silicide Layer

Growth of amorphous-titanium-silicidc and crystalline C49 TiSi2 in titanium/amorphous-silicon multilayer films was investigated using a combination of differential scanning calorimetry (DSC), thin film x-ray diffraction, Auger depth profiling, and cross-sectional transmission electron microscopy. The multilayer films had an atomic concentration ratio of 1Ti to 2Si and a modulation period of 30 nm. In the as-deposited condition, a thin amorphous-titanium-silicide layer was found to exist between the titanium and silicon layers. Heating the multilayer film from room temperature to 700 K caused the release of an exothermic heat over a broad temperature range and an endothermic heat over a narrow range. The exothermic hump was attributed to thickening of the amorphous-titanium silicide layer, and the endothermic step was attributed to the homogenization and/or densification of the amorphous-silicon and amorphous-titanium-silicide layers. An interpretation of previously reported data for growth of amorphous-titanium-silicide indicates an activation energy of 1.0 ± 0.1 eV and a pre-exponential coefficient of 1.9 × 10−7 cm2/s. Annealing at high temperatures caused formation of C49 TiSi2 at the amorphous-titanium-silicide/amorphous-silicon interfaces with an activation energy of 3.1 ± 0.1 eV. This activation energy was attributed to both the nucleation and the early stages of growth of C49 TiSi2. The heat of formation of C49 TiSi2 from a reaction of amorphous-titanium-silicide and crystalline titanium was found to be –25.8 ± 8.8 kJ/mol and the heat of formation of amorphous-titanium-silicide was estimated to be –130.6 kJ/mol.

Depth Profiling and Cross-Sectional Laser Ablation Ionization Mass Spectrometry Studies of Through-Silicon-Vias

2018 ◽  
Vol 90 (8) ◽  
pp. 5179-5186 ◽  
Author(s):  
Valentine Grimaudo ◽  
Pavel Moreno-García ◽  
Alena Cedeño López ◽  
Andreas Riedo ◽  
Reto Wiesendanger ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Laser Ablation ◽  
Depth Profiling ◽  
Ionization Mass Spectrometry ◽  
Ionization Mass ◽  
Cross Sectional ◽  
Through Silicon Vias ◽  
Silicon Vias

High Dose Implantation of Nickel into Silicon

1985 ◽  
Vol 54 ◽  
Author(s):  
G. J. Campisi ◽  
H. B. DIETRICH ◽  
M. Delfino ◽  
D. K. Sadana
Keyword(s):  
Electron Microscopy ◽  
Solid Phase ◽  
Ion Beam ◽  
Depth Profiling ◽  
Silicon Wafers ◽  
High Dose ◽  
Ion Beam Sputtering ◽  
Cross Sectional ◽  
Transmission Electron ◽  
Beam Sputtering

ABSTRACTSeveral silicon wafers were implanted with 58Ni+ at an energy of 170 keV and a current density of 12 μA cm-2 to doses between 5 × 1015 and 1.8 × 1018 ions cm-2. The substrates were phosphorus doped n-type <100> Czochralski grown silicon wafers. The wafers were water cooled during implantation and the surface temperatures was monitored with an infrared pyrometer and controlled to < 70°C. Samples were subsequently furnace annealed at 900°C for 30 min in nitrogen. The as-implanted and annealed samples were analyzed using cross-sectional transmission electron microscopy (XTEM), Rutherford backscattering (RBS) spectroscopy, spreading resistance depth profiling (SRP), and scanning electron microscopy (SEM). Micro-crystallites of NiSi2 (2–5nm) buried within an amorphous matrix formed during the 1.5 × 1017 ions cm-2 dose implantation. For higher doses above 3 × 1017 Ni+ cm-2, ion beam sputtering occurred. After annealing, rapid diffusion of nickel and solid-phase recrystallization of the amorphous regions occurred.

High Pressure Oxidation of Strained Si1−xGe Alloys

1990 ◽  
Vol 204 ◽  
Author(s):  
Christine Caragianis ◽  
David C. Paine ◽  
Carson B. Roberts ◽  
Everett Crisman
Keyword(s):  
High Pressure ◽  
Photoelectron Spectroscopy ◽  
Depth Profiling ◽  
Oxide Thickness ◽  
Misfit Dislocations ◽  
Atmospheric Conditions ◽  
Cross Sectional ◽  
Pressure Oxidation ◽  
Transmission Electron ◽  
High Pressure Oxidation

ABSTRACTThermal passivation of Si1−x Gex using high pressure (10,000 psi) oxidation was studied. Alloys of Si1−xGex (with x=5.4, 11.6, and 17 at. %) approximately 200 nm thick were oxidized using two processes: (i) dry oxygen at 10,000 psi at a temperature of 550°C and (ii) conventional, 1 atm steam at 800°C. The wet oxidation conditions were chosen to produce an oxide thickness comparable (=100 nm for xGe=11.6 at. %) to that obtained during high pressure oxidation at 550°C. Auger sputter depth profiling (AES), X-ray photoelectron spectroscopy (XPS), and cross-sectional transmission electron microscopy (TEM) were used to characterize the as-grown oxides. XPS studies reveal that high pressure oxides formed from all three of the alloys of Si1−xGex have greatly enhanced incorporation of Ge compared to those grown to a similar thickness under wet atmospheric conditions. We report that a significant benefit of this increase in Ge incorporation is the minimization of Ge enrichment near the oxide/Si1−xGex interface. Cross-sectional TEM images reveal a 30 nm thick Ge-rich band at the wet oxide/alloy interface and a dramatically thinner band (<5 nm) present at the oxide/alloy interface produced by high pressure oxidation. For the atmospheric oxidation samples, interfacial misfit dislocations were observed at the alloy/substrate interface indicating that the film relaxed during oxidation. In contrast, the high pressure samples showed no interfacial defects after oxidation.

Depth Profiling of Al Ion-Implantation Damage in SiC Crystals by Cathodoluminescence Spectroscopy

2008 ◽  
Vol 600-603 ◽  
pp. 615-618 ◽  
Author(s):  
Takeshi Mitani ◽  
Ryo Hattori ◽  
Masanobu Yoshikawa
Keyword(s):  
Ion Implantation ◽  
Point Defects ◽  
Depth Profiling ◽  
High Density ◽  
Cross Sectional ◽  
Implantation Damage ◽  
Cathodoluminescence Spectroscopy ◽  
Deep Region ◽  
Region 10 ◽  
Activation Annealing

Cross-sectional CL measurements have been performed on the cleaved surface of the Al-ion implanted 4H-SiC. The strong L1 luminescence that originates from the DI defect has been observed even in the deep region (~10 μm) where implanted ions do not penetrate. In the implanted layer, CL results show that high-density non-radiative defects remain even after activation annealing. Generation of the DI defect in the deep region is presumably attributed to the diffusion of point defects from the implanted layer.

Mapping Longitudinal Inhomogeneity in Nanostructures Using Cross-Sectional Spatial Raman Imaging

2020 ◽  
Vol 124 (11) ◽  
pp. 6467-6471 ◽  
Author(s):  
Manushree Tanwar ◽  
Devesh K. Pathak ◽  
Anjali Chaudhary ◽  
Priyanka Yogi ◽  
Shailendra K. Saxena ◽  
...  
Keyword(s):  
Raman Imaging ◽  
Cross Sectional ◽  
Longitudinal Inhomogeneity
Sign in / Sign up

Export Citation Format

Share Document