Telephone equipment has traditionally been housed in large buildings, sheds and outdoor cabinets. The cooling of these facilities has been carried out using traditional methods. However, in many of the new systems being developed and deployed such as broadband ISDN, cellular and/or cable, heat dissipation densities will increase substantially [1]. Furthermore, the introduction … [Read more...]
The coefficient of thermal expansion
This is the second technical data feature that deals with the coefficient of thermal expansion (CTE). The first technical data feature, incorporated in the September 1997 issue, covered semiconductor materials, leadframes and solder alloys. This issue will discuss the temperature dependence of the CTE and present data on other materials that are of importance to electronic … [Read more...]
Coefficient of thermal expansion
As complexity increases and dies and packages become even larger, temperature gradients also increase, leading to problems with thermal mismatch. Hence, thermomechanical analysis grows in importance. Apart from the temperature differences, the most important parameter describing thermally induced stress is the coefficient of thermal expansion (CTE, or °), expressed in units of … [Read more...]
Highly emissive ion beam textured surfaces for improved cooling of electronic devices
Continuous improvements in the cooling of electronic systems will berequired to keep pace with the rapid development of higher power chips.Currently, effective cooling relies (in part) on high surface area heatexchangers. Further improvements could be realized by increasing thesurface area of these devices. However, increasing the size of heatexchanger components is not a … [Read more...]
Thermal Conductivity
For most calculations regarding the thermal analysis of electronic systems, thermal conductivities of solid materials are required. It is felt that many designers would welcome a comprehensive list showing these values for certain classes of objects, such as PCB materials, leadframes, molding compounds, alloys etc.. This issue starts with 45 leadframe materials, the data for … [Read more...]