Time filter

Source Type

Kleff J.,Fraunhofer Institute for Reliability and Microintegration | Schlottig G.,IBM | Mrossko R.,AMIC Angewandte Micro Messtechnik GmbH | Steller W.,Fraunhofer Institute for Reliability and Microintegration | And 3 more authors.
2016 6th Electronic System-Integration Technology Conference, ESTC 2016 | Year: 2016

Interlayer cooling has been demonstrated to enable heat removal scaling in true 3D integration. This technology will unavoidably expose tier interconnects to coolant. If using electrically conductive liquids, such as water based coolants, the interconnects require a sealing mechanism to protect from short-circuiting. As an efficient technological solution we present a concentric ring sealing, realized around the interconnect in the very same alloy, thereby forming a joint of its own. We compare different aspect ratios of upper and lower joining parts, as well as single joint sealing and multiple joint sealing. We demonstrate the post-bonding states of the sealing using CuSnAg, AuSn transient liquid phase bonding (TLPB) and Cu-Cu thermocompression bonding. We lay emphasis on the resulting intermetallic compounds and present shear strengths of consistently beyond 30 MPa, reaching up to 85 MPa, which clearly shows the feasibility of the concept. © 2016 IEEE.

Brunschwiler T.,IBM | Mrossko R.,AMIC Angewandte Micro Messtechnik GmbH | Keller J.,AMIC Angewandte Micro Messtechnik GmbH | Ozsun O.,IBM | Schlottig G.,IBM
2016 6th Electronic System-Integration Technology Conference, ESTC 2016 | Year: 2016

In this study, a dual-side cooling topology based on a silicon cold plate and an electrical functional silicon-interposer with embedded fluid channels is benchmarked against mere back-side cooling. The back-side cold plate can be operated in a split-flow mode, whereas in the case of the interposer only a single in-and outlet can be implemented, which results in a cross-flow heat-exchange mode. An interposer cavity can be achieved by back-to-back bonding of interposer shells to achieve large channel heights. Sealing-ring structures and embedded TSVs are required to prevent contact between water and the electrically active TSVs. Optimal micro-channel dimensions of 150 μm width and 250 μm height were computed using an analytical convection model that considered mass and heat transfer. The impact of thermal interfaces arising from the electrical interconnects between the chip stack and the interposer was studied by numerical heat-conduction modeling. Neither, the interconnect type, rail or pillar, nor the application of thermally conductive underfills did result in significant changes in junction temperature. However, the dual-side cooling approach resulted in twice lower thermal gradients at the inlet of the cavity than with the back-side or front-side cooling option only. Although the cross-flow mode of the interposer increases the coolant temperature more than the cold plate, dual-side cooling extends the power dissipation limit for single dies and chip stacks substantially, supporting performance and efficiency scaling. © 2016 IEEE.

Agency: European Commission | Branch: FP7 | Program: CP | Phase: ICT-2013.3.1 | Award Amount: 5.85M | Year: 2014

Modular interposer architecture providing scalable heat removal, power delivery and communicationCarrICool will deliver a game-changing 3D packaging platform for scale-up of future, many-core, Exascale computing systems. The project will also develop a strategic supplier base in Europe for high-end HPC components and systems integration capabilities in the Exascale era. In CarrICool, advanced More-than-Moore components required to scale to energy efficient ExaFLOP computing performance will be developed and integrated into a modular and multifunctional interposer. Four critical packaging elements are implemented on the CarrICool interposer: i) Improved structural and electrical performance will be provided by expansion matching and high wiring density. ii) low thermal gradients for Beyond-CMOS and silicon photonic devices will be provided by integrated, single-phase, water-cooling cavities. iii) High granularity, distributed Buck-converters using integrated, high-quality power inductors will support energy-efficient power delivery to heterogeneous chip stacks. iv) Off-chip bandwidth will be enabled through low-cost and low-loss passive optical coupling to silicon photonic wave guides. CarrICool is targeting 2-fold improvement in heat removal, 10-fold higher voltage granularity and a 10-fold cost reduction in photonic packaging.Advanced characterization and simulation techniques will be implemented using physics-of-failure-based lifetime modelling to provide design-rules for improved system architecture. The performance of the four packaging elements of the modular interposer will be validated on three separate demonstrators and then integrated on the main CarrICool demonstrator. The CarrICool consortium pools interdisciplinary excellence, uniting ten partners from global companies (2), European SMEs (3), institutes (3) and academia (2) across seven European countries. An Advisory Board ensures the alignment of the project goals with user needs.

Agency: European Commission | Branch: FP7 | Program: CP-FP | Phase: NMP-2007-2.5-2 | Award Amount: 5.22M | Year: 2008

Micro- and nano-electronic components are multi-scale in nature, caused by the huge scale differences of the individual materials and components in these products. Consequently, product behaviour is becoming strongly dependent on material behaviour at the atomic scale. To prevent extensive trial-and-error based testing for new technology developments, new powerful quantitative knowledge-based modelling techniques are required. Current continuum-based finite element models rely intrinsically on extensive characterisation efforts to quantify the parameters present in these models (top-down approach). On the other hand, state-of-the-art models at atomic scale are able to describe the material behaviour at molecular level, but predictions at product scale are not feasible yet. Through direct coupling of molecular and continuum models, a multi-disciplinary approach in which experimentally validated multi-scale modelling methods will be developed in order to generate new materials and interfaces for System-in-Package (SiP) products with tailored properties and improved reliability within an industrial environment. In this approach, a user-friendly software tool will be realised which incorporates chemical, physical and electrical information from the atomic level into macroscopic models (bottom-up approach). Furthermore, new and efficient micro- and nano-scale measurement techniques are developed for obtaining detailed information about the most important phenomena at micro- and nano-scale and fast characterisation and qualification of SiPs. An additional important distinguishing part of this project is that, due to the composition of the consortium, the whole industrial development chain is covered: from material development, multi-scale models and experimental methods towards a fully functional commercial software package, ready to be used within an industrial environment.

Agency: European Commission | Branch: FP7 | Program: CP-FP | Phase: NMP.2012.2.1-1 | Award Amount: 4.56M | Year: 2013

Tomorrows micro-electronic devices will have to show more functionality and performance at smaller form factor, lower cost and lower energy consumption in order to be competitive on this multi-billion dollar market. Advanced system integration is thus inevitable, a trend bound to joining dissimilar materials with new packaging technologies. These processes must enable lower thermal resistances and higher interconnect density and device reliability under thermomechanical loading. Hyperconnect addresses these challenges by a radically new material joining process. The objective is to demonstrate superior electrical, thermal and thermomechanical performance and to combine design and technology with the support of simulation and testing. The central new idea comprises a sequential joint forming process, using self-assembly of nanoparticles, polymers and filler composite materials exploiting capillary action and chemical surface functionalisation: In other words, the formed joint reaches its outstanding properties by the very processing of the materials. This contrast to existing technology demands own understanding of the joint formation, joint property creation and the joint reliability. Therefore advanced experimental characterization and simulation techniques will accompany the material and technology development, in particular involving physics-of-failure-based lifetime modelling. Finally, the joint performance will be validated on four different demonstrators of industrial significance. To tackle these challenging issues the consortium pools the required interdisciplinary excellence, by uniting nine partners from industry, SMEs and academia of five European countries. Its members are convinced that these new developments will outperform commercially available solutions by one order of magnitude and will radiate out also to other fields in electronic packaging.

Agency: European Commission | Branch: FP7 | Program: CP | Phase: ICT-2011.3.1 | Award Amount: 9.51M | Year: 2012

Future electronic power devices and packages will need to demonstrate more performance and functionality at reduced cost, size, weight, energy consumption and thermal budget. Further, increasing reliability demands have also to be met by industry to be competitive in this growing multi-billion Euro market of heterogeneously integrated systems.To respond to these challenges, new innovative nano- and micro-technologies and materials, both of which are key enablers for advanced thermal and mechanical interfaces, have to be developed and compatibly integrated to obtain higher electrical, thermal and reliability performance under harsh environmental conditions.Nanotherms objective is to take up these challenges in design, technology and test:Novel approaches to thermal technologies with superior electrical, thermal and thermo-mechanical properties will be developed in the project and demonstrated on automotive, avionics, solid-state lighting and industrial applications. Parallel routes will be followed addressing nano-sinter-adhesive bonding, phonon-coupled VACNT joining, nano-functionalised nano-filled adhesive die attach and graphene-enhanced surfaces. The main principle common to all technologies is the exploitation of nano-effects to obtain outstanding interconnect properties by especially developed processes.In parallel, a multi-scale and multi-domain modelling framework will furnish guidelines for materials design by various approaches from ab-inito up to continuum modelling and verified by corresponding experimental techniques.The consortium, composed of 18 partners from industry, SME and academia out of 8 European countries, embodies the necessary excellence and interdisciplinarity to address these tasks successfully. We are convinced that Nanotherms results will enable the next generation of heterogeneously integrated power packages, cut down thermal interface resistance at least by 50% and impact also on other power system-in-package configurations.

Auersperg J.,Fraunhofer Institute for Electronic Nano Systems | Auersperg J.,AMIC Angewandte Micro Messtechnik GmbH | Vogel D.,Fraunhofer Institute for Electronic Nano Systems | Auerswald E.,Fraunhofer Institute for Electronic Nano Systems | And 2 more authors.
2011 IEEE 13th Electronics Packaging Technology Conference, EPTC 2011 | Year: 2011

The application of copper-TSVs for 3D-IC-integration generates novel challenges for reliability analysis and prediction, i.e. to master multiple failure criteria for combined loading including residual stresses, interface delamination, cracking and fatigue. So, the thermal expansion mismatch between copper and silicon yields to stress situation in silicon surrounding the TSVs which is influencing the electron mobility and as a result the transient behavior of transistors. Furthermore, pumping and protrusion of copper is a challenge for Back-end of Line (BEoL) layers of advanced CMOS technologies already during manufacturing. These effects depend highly on the temperature dependent elastic-plastic behavior of TSV-copper and the residual stresses determined by the electro deposition chemistry and annealing conditions. © 2011 IEEE.

Brunschwiler T.,IBM | Schindler-Saefkow F.,AMIC Angewandte Micro Messtechnik GmbH | Gordin R.,IBM | Haupt M.,AMIC Angewandte Micro Messtechnik GmbH | Schlottig G.,IBM
Thermomechanical Phenomena in Electronic Systems -Proceedings of the Intersociety Conference | Year: 2014

Percolating and neck-based thermal underfills with significant improvements in thermal conductivity compared with capillary underfills are currently under development. They could be applied between dies to improve the heat dissipation through a 3D chip stack. In this parametric study, we provide insights into the thermal, mechanical, thermo-mechanical and electrical properties achievable by this new composite material class. The primary objective of the investigation is the linear buckling phase of monodisperse spherical filler particles confined between two parallel plates with a fill fraction range of 48.7% to 61.3% as observed by experiment. The introduction of necks between the point contacts of the filler particles had the most significant impact on the composite effective material properties, resulting in an increase in thermal conductivity, stiffness and a drop in the thermal expansion coefficient. The high stiffness could cause delamination of the underfill in chip corners because of high shear forces and hence may have to be mitigated. Finally, two design points for the composite were proposed, respecting the target values for the percolating and neck-based thermal underfill, with a predicted effective thermal conductivity of 1.9 and 3.6 W/m-K. © 2014 IEEE.

Schlottig G.,IBM | Schindler-Saefkow F.,AMIC Angewandte Micro Messtechnik GmbH | Zurcher J.,IBM | Michel B.,IBM | Brunschwiler T.,IBM
Proceedings of the 2013 IEEE 15th Electronics Packaging Technology Conference, EPTC 2013 | Year: 2013

To ensure functionality and integrity of electronic package interconnects, underfill materials are designed to meet a desired stiffness that bridges the thermal expansion behavior of die, substrates and interconnects. The underfill protects the interconnects from thermal strains and environmental influences. Recently, the thermal conductivity became a critical parameter too, to efficiently dissipate heat from 3D chip stacks. Accordingly, the particle loading is increased beyond the percolation threshold, which was demonstrated by sequentially fabricated materials with a 5fold thermal conductivity improvement. This paper explores the thermo-mechanical properties of the novel percolating thermal underfills considering alumina filler particles. The changing behavior of underfill composites has been well described for various fillers and matrices both theoretically and experimentally. But percolation was excluded so far for lack of relevance. We compare the numerical predictions of composites' Young's moduli around the filler percolation threshold to known effective-medium approximation bounds of polydisperse materials. The simulations were based on 3D unit cells of the face centered cubic packing in different lattice orientations and consider both filler and matrix materials. A significant change in characteristics is observed close to percolation. However, the 100 and the 110 lattice orientations give a 5% Young's modulus difference only. The numerical predictions are within effective-medium approximation bounds, but appear closer to either upper or lower bounds depending on the filler fraction. The presented results extend the possible thermo-mechanical parameter space of conventional underfills to percolating composites. © 2013 IEEE.

Agency: European Commission | Branch: FP7 | Program: JTI-CS | Phase: JTI-CS-2010-3-ECO-01-007 | Award Amount: 199.99K | Year: 2011

The FATIMA project proposed by the consortium will work on testing and fatigue prediction of carbon fiber reinforced plastics (CFRP) as required in call JTI-CS-2010-3-ECO-01-007. The challenging objective is to go beyond the state of the art in terms of approaches to account for humidity, multi-ply and multi-axiality effects in organic laminate structures. Intensive work in the field resulted in a number of concepts for accelerated lifetime predictions for carbon fiber reinforced polymers. Within FATIMA, these concepts will be adapted to the material provided by the partners of the Clean Sky consortium. The proposed methodology and integration into the fatigue testing procedure will approach expansions addressing humidity effects, different stack-up structures and combined loading of these composite structures. Appropriate models of a multitude of specific laminate structures will be provided as a tool box for composing desired laminates consisting of plies with known behavior. Failure criteria developed for predicting the damage in composite materials due to multi-axial loads will be evaluated, selected and advanced to meet the objectives of the call.

Loading AMIC Angewandte Micro Messtechnik GmbH collaborators
Loading AMIC Angewandte Micro Messtechnik GmbH collaborators