With the on-going increase in the power density of electronic devices, thermal management remains a central issue for upholding device performance and reliability. Thermal interface materials (TIMs), used to conduct heat across the multiple interfaces between the device and heat sink, with unprecedentedly low thermal resistance and a high degree of mechanical compliance to accommodate mismatche...

Composites obtained by bonding materials with the same crystal structure and different chemical compositions can create new functions that do not exist in conventional concepts. We have succeeded in bonding polycrystalline YAG and Nd:YAG ceramics without any interstices at the bonding interface, and the bonding state of this composite was at the atomic level, similar to the grain boundary struc...

The lattice thermal conductivity (κ) of hexagonal Ge2Sb2Te5 (h-GST) is studied via direct first-principles calculations. We find significant intrinsic anisotropy (κa/κc~2) of κ in bulk h-GST, with the dominant contribution to κ from optic phonons, ~75%. This is extremely unusual as the acoustic phonon modes are the majority heat carriers in typical semiconductors and insulators. The anisotropy ...

The coefficient of thermal expansion (CTE) and the thermal conductivity are the two key parameters to consider when selecting a particular substrate material for a die bonding process. We will discuss here a model to determine the substrate material giving the best chip reliability expectations for GaAs and InP laser chips. In that respect, a comparison of the thermo-mechanical stresses induced...

An optical fiber sensor surface bonded onto a host structure and subjected to a temperature change is analytically studied in this work. The analysis is developed in order to assess the thermal behavior of an optical fiber sensor designed for measuring the strain in the host structure. For a surface bonded optical fiber sensor, the measuring sensitivity is strongly dependent on the bonding char...

The effects of bonding temperatures on the composite properties and reliability performances of anisotropic conductive films (ACFs) for flip chip on organic substrates assemblies were studied. As the bonding temperature decreased, the composite properties of ACF, such as water absorption, glass transition temperature (Tg), elastic modulus (E 0) and coefficient of thermal expansion (a), were imp...

This contribution describes recent applications of supercomputers to describing phenomena occurring on the nanometer scale, which evade direct experimental observation. Dependable ab initio calculations can determine, whether all-carbon nanostructures may become metallic or even magnetic. Computer simulations help us understand, how to design nanostructures with unusual properties, such as high...

The effect of bonding parameters on the reliability of thick Al wire bond is investigated. Samples were prepared with 25 different designs with 5 different bonding parameters such as time, ultrasonic power, beginforce, end-force and touch-down steps (pre-compression) with 5 levels. The bond signals of ultrasonic generator were collected during bonding in order to obtain prior quality informatio...

CMOS compatible metallic hermetic sealing using Al-Ge eutectic alloy for packaging MEMS devices for harsh environments has been developed. The effects of various bonding parameters on the bond quality have been extensively reported. The reliability of this eutectic joint subjected to high operating temperatures involved in deep oil well logging application has been investigated with the specifi...