bluuebunny/crossref_metadata_2025_split huggingface dataset:
Glass Substrates for Advanced Packaging
Authors: Shorey Aric , Pollard Scott 
Published: October 2015

There has been substantial work done in the past few years to apply glass solutions for Advanced Packaging. Advantages of glass based solutions create significant opportunities by leveraging economies of scale, forming substrates at design thickness and leveraging thermal and electrical properties.
A lot of work is being done to validate the value of glass as an interposer substrate. The ability to leverage both wafer and panel-based metallization strategies for filling glass vias has been shown. Transitioning these processes to cost-effectiveness and high throughput has shown great promise. The electrical performance of glass relative to silicon at high frequencies makes glass solutions very attractive, particularly in RF applications. Electrical models and characterization have demonstrated the advantages of the insulating properties of glass, and its positive impact on functional performance. Reliability tests show that glass solutions can meet device requirements. The substantial progress and readiness in these areas will be presented.
Glass based solutions in panel format provide exciting and cost effective industry opportunities by leveraging economies of scale and glass forming technology. Existing technologies can be used to fill glass vias in a panel format, as well as apply redistribution layers. We will present the status of leveraging panel based technology to enable glass interposers.
Fast Etching of Microscale Structures by Bombardment with Electrosprayed Nanodroplets
Authors: Grustan-Gutierrez Enric , Borrajo-Pelaez Rafael , Gamero-Castaño Manuel 
Published: October 2015

In this article Si substrates protected by Shipley 1827 and Au masks are sputtered with electrosprayed nanodroplets to produce microscale structures. Silicon is used as a benchmark to assess the effect of the physical sputtering of nanodroplets on more interesting chemically inert materials such as SiC and GaN.
The use of Shipley 1827 as a patterning mask provides a virtually infinite etching selectivity between substrate and photoresist at the cost of non-perpendicular wall profiles and debris redeposition. After 60 minutes of processing the target at a sputtering rate of 244 nm/min, a fraction of the sputtered material deposits back on the substrate forming a protective layer that stops any further sputtering.
In a second set of experiments the selectivity between Si and Au to be used as a potential mask is studied. The maximum selectivity is 64.17, and is obtained at an etching rate of 385 nm/min. An increase of the etching rate produces a sharp drop on the selectivity between Au and Si.
The Importance of Effective Root Cause Analysis of Failures in High Reliability Microelectronics Applications: A Case Study
Authors: Schulz Gwen 
Published: October 2015

The screening and detection of failures in high reliability electronics is crucial to mission success. The governing standards for microelectronic components prescribe effective screens to address known failure modes during the manufacture of the components. When failures are detected outside of the normal component screening process such as in the next higher assemblies, the analysis of such failures to root cause is even more crucial. Effective root cause analysis requires collaboration among personnel having expertise in many areas, both technical and organizational. Too often, the analysis stops at the ‘how’ a part failed, rather than the ‘why’ and true root cause determination. Failures may not only represent defects in the technical aspects of the design, materials or application of the hardware, but may also be related to human organizational factors such as the competing interests of time, quality and cost. The analysis must extend beyond the forensic data into the human organization and the interaction between people, process and hardware.
In this paper, the author illustrates an effective root cause corrective action (RCCA) analysis process through the discussion of a microelectronics packaging case study. The case involved failure of high reliability hybrid microelectronic components at the next higher assembly level. The case study provides insights into the root cause analysis process as well as awareness that component level high reliability screening is not impervious. It is critical for the next level user to have the expertise in their organization to understand both the how and the why of such failures.
The case study describes a failure related to loose metal particles inside a hermetically sealed multilayer ceramic package which had passed Particle Impact Noise Detection (PIND) screening at the supplier. Root cause analysis determined the cause for the screening escape as well as the cause of the metal particles, and effective corrective actions were implemented at both the component supplier and Honeywell. Technical causes include improper package design, weld schedule and screening methods. Organizational causes include inadequate documentation, lack of training and failure to react to prior failures. The root cause investigation team was a multi-discipline group from Honeywell, our customer, and the component supplier, with additional consulting input from other suppliers, equipment manufacturers and industry experts.
Design of a Miniaturized Vibrating Beam Power Converter
Authors: Marinis Thomas F. , Soucy Joseph W. 
Published: October 2015

One of the largest components on miniaturized, multichip modules is the chip inductor associated with the onboard DC to DC power converter. It is an essential component for efficient conversion of the system voltage to the operating voltage of the module. In a previous paper, we described how vibrating capacitor structures could be used to perform inductor functions. In this paper, we focus on the specific application of an on-board power converter. Our vision is for a MEMS scale device that could be attached to the back of a chip as an appliqué or embedded in an interposer on which the chip was mounted. It would function as a DC to DC converter to extract power from the system buss and supply it to the chip at its required operating voltage.
This device consists of a long, flat, rectangular, vibrating beam that is sandwiched between two fixed electrodes. It is clamped at its two ends and electrically connected to ground. On one of the fixed electrodes, which we refer to as the source electrode, a bias potential is applied through a resistor connected to a battery. The motion of the beam relative to the source electrode generates a sinusoidal like fluctuation in the potential between them. The amplitude of this alternating voltage is set by the amplitude of the beam vibration and the nominal gap between the beam and source electrode. It can be made insensitive to variations in battery voltage, by controlling the amplitude of the beam vibrations. The sinusoidal portion of the bias voltage can be extracted through a DC blocking capacitor connected to the source electrode. By passing it through a rectifier and filter capacitor, it can be used as a stable DC supply voltage.
The beam vibration is initiated and sustained by voltage pulses applied to the other fixed electrode, which we refer to as the drive electrode. A logic circuit connected to the source electrode monitors its sinusoidal voltage and applies a pulse to the drive electrode when two criteria are met. First, the sinusoidal voltage must be rising, which occurs when the beam is moving away from the source electrode and towards the drive electrode. Second, the time average of the sinusoidal voltage must be below its desired set point, which means that more energy must be injected into the beam. When voltage is applied to the drive electrode, it exerts a force on the vibrating beam that pulls it towards the drive electrode.
We have constructed a Mat Lab model of a vibrating beam power converter and have been using it to examine a number of design factors including, physical size, vibration frequency and amplitude, values for the DC blocking and output filter capacitors, as well as the logic used to apply pulses to the drive electrode. Our intent is to develop a sufficient understanding of the device operational and physical design requirements to enable us to build a prototype device.
Composition and Form: How Feedthrough Design Affects Package Hermeticity
Authors: Share Richard R. 
Published: October 2015

Ceramic-insulated feedthroughs have been in use in microelectronic packages for decades. Their track record is generally good, but not unblemished. This is because ceramic insulators tend to crack under stress - the stress of assembly temperatures, thermal shock screening and fine leak pressurization. The cracks often propagate to surface termination, forming leak paths and rendering afflicted packages non-hermetic. Package manufacturers have long battled this phenomenon and developed a number of creative designs that attempt to prevent, minimize and/or contain this inherent vulnerability. Yet it persists.
To successfully prevent this undesired effect, the factors causal to its origination must be identified, understood and eliminated. That is to say, the effects of the constituent components or parts – the package wall, insulator, conductor and brazes – in summation and subtraction, in function and failure, on the integrity and reliability of the whole must be understood in order to design a package robust to thermal and pressural excursions. The optimal design will consist of components with complimentary properties of composition and form; properties that in interaction with one another multiplicatively enhance package robustness and reliability. Any other design will be vulnerable to failure.
Herein, the effects of the component properties of composition and form on the structural integrity, reliability and hermeticity of metal cases employing ceramic insulators will be discussed, the primary factors causal to contemporary feedthrough hermeticity failures will be introduced in the form of a simplified force model, an optimization case study will be presented in brief, and currently utilized design features will be objectively compared and assessed.
Assembly and Scaling Challenges for 2.5D IC
Authors: Wang Liang , Woychik Charles G. , Gao Guilian , McGrath Scott , Shen Hong , Tosaya Eric , Arkalgud Sitaram 
Published: October 2015

2.5D technology is gaining acceptance in the industry and an increasing number of products are beginning to enter volume manufacturing. As with all interconnect technologies, the key metrics driving the transition include higher computing performance, lower power consumption, smaller form factor, increased bandwidth and reduced latency (interconnect delay). In order to transition from today's low volumes to High Volume Manufacturing (HVM), the concerns of warpage control, thermal dissipation, cost (yield and throughput) and overall technology scalability for future generations need to be addressed rapidly. The solutions in these relatively new packaging technologies encompass design/layout, material, process and integration choices.
With these concerns as a backdrop, our paper will discuss our approach to optimizing 2.5D assembly for HVM. We will begin with a review of our test vehicle and our overall choices of substrate, interposer and die dimensions. Three different 2.5D assembly approaches that have been investigated at Invensas for warpage control, ease of process, and impact on yield and reliability will be discussed in detail. We will present our results from critical areas including temporary bonding, thermo-compression bonding, mass reflow, thin wafer/die handling, flux, underfill and molding. This paper will present our understanding of the underlying principles governing the technology bottlenecks in advanced packaging and the three flows will be compared with an assessment of their advantages and disadvantages. In addition, we will also provide the results of our cost modeling work. We will finish by making recommendations for an optimized assembly process flow.
Noble gas signatures in Greenland: Tracing glacial meltwater sources
Authors: Niu Yi , Castro M. Clara , Aciego Sarah M. , Hall Chris M. , Stevenson Emily I. , Arendt Carli A. , Das Sarah B. 
Published: October 2015

AbstractThis study represents the first comprehensive noble gas study in glacial meltwater from the Greenland Ice Sheet. It shows that most samples are in disequilibrium with surface collection conditions. A preliminary Ne and Xe analysis suggests that about half of the samples equilibrated at a temperature of ~0°C and altitudes between 1000 m and 2000 m, with a few samples pointing to lower equilibration altitudes and temperatures between 2°C and 5°C. Two samples suggest an origin as melted ice and complete lack of equilibration with surface conditions. A helium component analysis suggests that this glacial meltwater was isolated from the atmosphere prior to the 1950s, with most samples yielding residence times ≤ 420 years. Most samples represent a mixture between a dominant atmospheric component originating as precipitation and basal meltwater or groundwater, which has accumulated crustal 4He over time.
Velocity‐ and slip‐dependent weakening in simulated fault gouge: Implications for multimode fault slip
Authors: Ito Yoshihiro , Ikari Matt J. 
Published: October 2015

AbstractIn addition to the velocity dependence of friction, slip dependence may play a major role before and during earthquake slip in fault zones. We performed laboratory friction experiments on simulated fault gouges, measuring both the velocity and slip dependence of friction in velocity step tests. The pure velocity‐dependent component of friction measured over short displacements shows both velocity strengthening and velocity weakening friction, depending on the amount of slip considered. However, we observe that increases in sliding velocity can induce slip weakening behavior which overwhelms the velocity dependence resulting in large overall weakening, especially at rates > 1 µm/s. On natural tectonic faults, this suggests that a velocity perturbation, such as coseismic rupture propagating onto a fault patch, could induce instability via large slip weakening. Therefore, a fault which is experiencing a transient slip or slow earthquakes may be more easily induced to slip coseismically if a dynamic rupture from large earthquake propagates onto the fault.
Positive trends in Southern Hemisphere carbonyl sulfide
Authors: Kremser Stefanie , Jones Nicholas B. , Palm Mathias , Lejeune Bernard , Wang Yuting , Smale Dan , Deutscher Nicholas M. 
Published: October 2015

AbstractTransport of carbonyl sulfide (OCS) from the troposphere to the stratosphere contributes sulfur to the stratospheric aerosol layer, which reflects incoming short‐wave solar radiation, cooling the climate system. Previous analyses of OCS observations have shown no significant trend, suggesting that OCS is unlikely to be a major contributor to the reported increases in stratospheric aerosol loading and indicating a balanced OCS budget. Here we present analyses of ground‐based Fourier transform spectrometer measurements of OCS at three Southern Hemisphere sites spanning 34.45°S to 77.80°S. At all three sites statistically significant positive trends are seen from 2001 to 2014 with an observed overall trend in total column OCS at Wollongong of 0.73 ± 0.03%/yr, at Lauder of 0.43 ± 0.02%/yr, and at Arrival Heights of 0.45 ± 0.05%/yr. These observed trends in OCS imply that the OCS budget is not balanced and could contribute to constraints on current estimates of sources and sinks.
Distinct effects of global mean warming and regional sea surface warming pattern on projected uncertainty in the South Asian summer monsoon
Authors: Chen Xiaolong , Zhou Tianjun 
Published: October 2015

AbstractSignificant uncertainties in the projected South Asian summer monsoon (SASM) have been observed in the released Fifth Phase of the Coupled Model Intercomparison Project (CMIP5) data set. Knowing what factors dominate the uncertainties is critical to constraining the local climate changes. Analyzing state‐of‐the‐art climate model simulations under the RCP8.5 scenario, we find that uncertainties in the circulation primarily result from the divergent global mean warming across models. In contrast, the compensation between dynamic and thermodynamic effects makes the spread in monsoon rainfall independent of the global temperature change. Via a suite of sensitivity experiments, we identify that the uncertainties in the SASM rainfall are dominated by the Indo‐Pacific sea surface temperature (SST) warming pattern, especially around the western central Pacific. The SST warming pattern plays its role by changing the zonal temperature gradient over the SASM region and modulating the interhemispheric moisture transport. We highlight that the SST warming patterns require more attention in constraining the projected regional rainfall changes.
High‐resolution in situ observations of electron precipitation‐causing EMIC waves
Authors: Rodger Craig J. , Hendry Aaron T. , Clilverd Mark A. , Kletzing Craig A. , Brundell James B. , Reeves Geoffrey D. 
Published: October 2015

AbstractElectromagnetic ion cyclotron (EMIC) waves are thought to be important drivers of energetic electron losses from the outer radiation belt through precipitation into the atmosphere. While the theoretical possibility of pitch angle scattering‐driven losses from these waves has been recognized for more than four decades, there have been limited experimental precipitation observations to support this concept. We have combined satellite‐based observations of the characteristics of EMIC waves, with satellite and ground‐based observations of the EMIC‐induced electron precipitation. In a detailed case study, supplemented by an additional four examples, we are able to constrain for the first time the location, size, and energy range of EMIC‐induced electron precipitation inferred from coincident precipitation data and relate them to the EMIC wave frequency, wave power, and ion band of the wave as measured in situ by the Van Allen Probes. These observations will better constrain modeling into the importance of EMIC wave‐particle interactions.
Responses of relativistic electron fluxes in the outer radiation belt to geomagnetic storms
Authors: Xiong Ying , Xie Lun , Pu Zuyin , Fu Suiyan , Chen Lunjin , Ni Binbin , Li Wen , Li Jinxing , Guo Ruilong , Parks G. K. 
Published: October 2015

AbstractGeomagnetic storms can either increase or decrease relativistic electron fluxes in the outer radiation belt. A statistical survey of 84 isolated storms demonstrates that geomagnetic storms preferentially decrease relativistic electron fluxes at higher energies, while flux enhancements are more common at lower energies. In about 87% of the storms, 0.3–2.5 MeV electron fluxes show an increase, whereas 2.5–14 MeV electron fluxes increase in only 35% of the storms. Superposed epoch analyses suggest that such “energy‐dependent” responses of electrons preferably occur during conditions of high solar wind density which is favorable to generate magnetospheric electromagnetic ion cyclotron (EMIC) waves, and these events are associated with relatively weaker chorus activities. We have examined one of the cases where observed EMIC waves can resonate effectively with >2.5 MeV electrons and scatter them into the atmosphere. The correlation study further illustrates that electron flux dropouts during storm main phases do not correlate well with the flux buildup during storm recovery phases. We suggest that a combination of efficient EMIC‐induced scattering and weaker chorus‐driven acceleration provides a viable candidate for the energy‐dependent responses of outer radiation belt relativistic electrons to geomagnetic storms. These results are of great interest to both understanding of the radiation belt dynamics and applications in space weather.
Joint measurement of the atmospheric muon flux through the Puy de Dôme volcano with plastic scintillators and Resistive Plate Chambers detectors
Authors: Ambrosino F. , Anastasio A. , Bross A. , Béné S. , Boivin P. , Bonechi L. , Cârloganu C. , Ciaranfi R. , Cimmino L. , Combaret Ch. , D'Alessandro R. , Durand S. , Fehr F. , Français V. , Garufi F. , Gailler L. , Labazuy Ph. , Laktineh I. , Lénat J.‐F. , Masone V. , Miallier D. , Mirabito L. , Morel L. , Mori N. , Niess V. , Noli P. , Pla‐Dalmau A. , Portal A. , Rubinov P. , Saracino G. , Scarlini E. , Strolin P. , Vulpescu B. 
Published: October 2015

AbstractThe muographic imaging of volcanoes relies on the measured transmittance of the atmospheric muon flux through the target. An important bias affecting the result comes from background contamination mimicking a higher transmittance. The MU‐RAY and TOMUVOL collaborations measured independently in 2013 the atmospheric muon flux transmitted through the Puy de Dôme volcano using their early prototype detectors, based on plastic scintillators and on Glass Resistive Plate Chambers, respectively. These detectors had three (MU‐RAY) or four (TOMUVOL) detection layers of 1 m2 each, tens (MU‐RAY) or hundreds (TOMUVOL) of nanosecond time resolution, a few millimeter position resolution, an energy threshold of few hundreds MeV, and no particle identification capabilities. The prototypes were deployed about 1.3 km away from the summit, where they measured, behind rock depths larger than 1000 m, remnant fluxes of 1.83±0.50(syst)±0.07(stat) m−2 d−1 deg−2 (MU‐RAY) and 1.95±0.16(syst)±0.05(stat) m−2 d−1 deg−2 (TOMUVOL), that roughly correspond to the expected flux of high‐energy atmospheric muons crossing 600 meters water equivalent (mwe) at 18° elevation. This implies that imaging depths larger than 500 mwe from 1 km away using such prototype detectors suffer from an overwhelming background. These measurements confirm that a new generation of detectors with higher momentum threshold, time‐of‐flight measurement, and/or particle identification is needed. The MU‐RAY and TOMUVOL collaborations expect shortly to operate improved detectors, suitable for a robust muographic imaging of kilometer‐scale volcanoes.
Sensitivity of simulated tropospheric CO to subgrid physics parameterization: A case study of Indonesian biomass burning emissions in 2006
Authors: Field Robert D. , Luo Ming , Kim Daehyun , Del Genio Anthony D. , Voulgarakis Apostolos , Worden John 
Published: October 2015

AbstractRecent cumulus and turbulence parameterization changes to the NASA GISS ModelE2 have improved representation of the Madden‐Julian Oscillation and low cloud distribution, but their effect on composition‐related quantities is not known. In this study, we simulate the vertical transport of carbon monoxide (CO) from uncontrolled biomass burning in Indonesia in late 2006, during which uniquely high CO was detected in the upper troposphere. Two configurations of ModelE2, one without the changes (AR5) and one with the changes (AR5′), are used for an ensemble simulation of the transport of CO from the biomass burning. The simulation results are evaluated against new CO profiles retrieved jointly from the Aura Tropospheric Emission Spectrometer and the Microwave Limb Sounder. Modeled upper tropospheric CO using the AR5 physics was unrealistically high. The AR5′ physics suppress deep convection that reaches near the tropopause, reducing vertical transport of CO to the upper troposphere and bringing the model into better agreement with satellite CO. In this regard, the most important changes were related to the strength of entrainment of environmental air into the convective column, the strength of re‐evaporation above cloud base, and a negative plume buoyancy threshold based on density temperature. This study illustrates how individual, noncomposition model changes can lead to significantly different modeled composition, which in this case improved agreement with satellite retrievals. This study also illuminates the potential usefulness of CO satellite observations in constraining unobservable processes in general circulation models.