The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
One of the present trends in microelectronic is the embedding of electronic devices directly into structural components. This integration of smart systems into hybrid and light weight structures also is a main objective of MERGE, the research cluster of excellence on Technologies for Multifunctional Lightweight Structures. The integrated silicon sensor system, also called stress monitor chip system...
This paper presents a systematic study of sintered silver. In order to investigate the correlation between processing conditions, microstructures, thermal and electrical properties, sintered silver samples have been prepared in 27 variations of sintering temperature between 200°C and 270°C and sintering pressure between 5 MPa and 25 MPa. For the thermal and electrical characterization, the innovative...
Theoretical analyses on the thermo-mechanical behavior of power modules designed in a new buildup and interconnection technology based on silver sintering and electroplated copper interconnects have been made. The characteristic difference to other technologies can be seen in the replacement of bonding wires by planar copper interconnects and the high voltage applicability of the resulting modules...
Finite Element Simulations of highly integrated and large electronics packages with detailed elastic-plastic material modeling of thousands of solder balls are still challenging tasks for today's computation systems. The complex geometry and mesh and the usage of time consuming creep laws for solder materials makes it nearly impossible to calculate different geometries or process parameters. This...
Flip chip or wire bonding on highly sensitive low-k and ultra-low-k (ULK) BEoL-structures is an important issue concerning the thermo-mechanical integrity. To assess the thermo-mechanical stress situation in BEoL structures under the loading conditions of wire bonding and pull testing using Finite-element-analyses (FEA), a suitable approach is necessary. In particular, the phenomenon of friction at...
The dependency of the failure mechanisms of PCB/BGA assemblies subjected to drop impact on board designs variations is investigated in this study. Two key parameters are considered: the copper pad size and the trace routing. It is shown that the assemblies can exhibit various failure modes such as copper trace crack, pad cratering on PCB or crack at interposer on package side by varying these board...
An accelerated and cost-effective characterization method for bi-material interfaces under cyclic loading using a Miniaturized Sub-Critical Bending (MSCB) test setup is presented. The Modified Single Leg Bending (MSLB) samples are acquired directly from production-line, Thin Quad Flat Package (TQFP). Under sub-critical cyclic loading, crack was found to occur at the polymer-metal interface. The crack...
An in-situ and cost-effective numerical-experimental approach for fatigue characterization of bi-material interfaces in Microelectronic Packages is presented. In this method using a sample-centered approach a Miniaturized Sub-Critical Bending (MSCB) test setup is designed and fabricated based on the samples that are acquired directly from production-line. The accuracy of the results and stiffness...
The determination of the mechanical and thermo-mechanical behaviour of a UHF-RFID-based smart system embedded in a transmission belt has been the goal of the work reported in this paper. The complex bending and thermal loads occurring during fabrication and service are taken into account by finite element simulations using ABAQUS standard™. In order to achieve quantitatively correct results, dynamic...
Knowledge and control of local stress development in BEoL stacks and nearby TSVs in advanced 3D integrated devices is a key to their thermo-mechanical reliability. The paper presents a combined simulation / measurement approach to evaluate stresses generated in the result of the TSV and BEoL stack manufacturing and 3D bonding processes. Stress measurement methods of high spatial resolution capability...
The stress sensing system, which has been developed recently, allows measuring the magnitudes and the distribution of mechanical stresses induced in the silicon dies during fabrication and testing of the electronic packages. The studies already presented in the last years focused on the effects of temperature cycling, 4-point-bending, moisture swelling, and molding. This paper reports the results...
The steady state method is a commonly used and in principle simple way to measure thermal resistance and conductivity of thermal interface materials (TIMs). The sample must be positioned between a hot and a cold plate with constant temperatures, whereby a heat flow through the sample and temperature gradient across the sample are generated. To determine the thermal resistance of the sample the heat...
Transient liquid phase (TLP) soldering is one option for high temperature interconnects with the advantage of processing conditions being close to those for conventional soldering. In the Cu-Sn system addressed in the paper, a high post-processed melting point of the solder interconnects is achieved due to the formation of Cu6Sn5 and Cu3Sn intermetallic compounds (IMC). A specific low melting solder...
In this paper, an accelerated and cost-effective characterization method for bi-material interfaces under cyclic loading using a Miniaturized Cyclic Mixed-mode Bending (MCMB) test setup is presented. The Modified Single Leg Bending (MSLB) samples are acquired directly from production-line Thin Quad Flat Package (TQFP) which provide a mixed-mode I + II loading condition. Under sub-critical cyclic loading,...
The steady state method is a commonly used and in principle simple way to measure thermal resistance and conductivity of thermal interface materials (TIMs). A heat flow through the TIM has to be generated and the temperature gradient across the TIM has to be measured. This is also defined by the ASTM standard ASTM D5470 [4]. To generate the heat flow the TIM must be positioned between a hot and a...
In automotive electronics, complex automotive functionalities are managed by car's computers such as electronic control units (ECU). Albeit extremely rare, accidental drop impacts may occur during transportation or mounting ECUs on automobiles, damaging the built-in printed circuit board (PCB)/ball grid array (BGA) package assembly. However, due to larger package dimensions together with heavy components...
The strength of poly-silicon membranes was investigated by experimental tests and numerical simulations. A new fracture test has been developed that replicates the loading situation under real service conditions well but with higher stress level. A set of 45 membranes was tested at each of the three positions on the wafer in order to assure statistical accuracy and to evaluate the strength distribution...
The ongoing development towards increasing functional density and performance drives the improvement of IC packaging and interconnection technologies. However, new integration technologies, such as through silicon vias (TSVs) for 3D stacking for heterogeneous systems as well as rigid micro-bumps together with the utilization of delicate new (porous ultra low-k) materials weaken the mechanical stability...
A parametric transient thermo-electrical coupled PSPICE macro model for a power cable as well as the verification results of the experimental and finite element simulation will be introduced. The paper describes the modeling and simulation of a simplified, single-core cable parametric model, for the use in a circuit simulator e.g. PSPICE. The verification of the simulation data between ANSYS and PSPICE...
Deformation of trenches due to residual stresses in TiN may result in Cu voids forming especially at shrinking feature sizes of trenches and vias and introducing low-k dielectrics between Cu interconnects. The influence of residual stress therefore has been investigated in a parametric study using Finite Element analyses (FEA) to discover the correlation between the TiN stresses and failure occurrence...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.