Here is the abstract you requested from the ASP_2016 technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|INVESTIGATION OF ACCEPTABLE MODULUS OF ELASTICTY FOR A LOW STRESS DIE ATTACH ADHESIVE|
|Keywords: Die Attach Adhesive, Modulus of Elasticity, Low Stress|
|Those distinguishing qualities or characteristics that are used to describe a substance in the absence of external forces are referred to as physical properties. A description of the physical behavior of a material would include such characteristics as specific heat, thermal conductivity, coefficient of thermal expansion, color, refractive index, density, and electrical conductivity. For many purposes, the engineer is greatly concerned about the physical properties of the material particularly on materials to be used for thermal control devices, electrical, equipment, and so forth. In the semiconductor industry, these properties are likewise very crucial in achieving good assembly manufacturability and package reliability. Typical Bill-of-Materials (BOM’s) in Integrated Circuits (IC’s) includes the substrate, silicon die, bonding wire, encapsulant, and die bonding paste or adhesive. To have a reliable solution of less coefficient of thermal expansion (CTE) mismatch inside the package, each material property combinations and interactions must be considered. With this requirement, low stress materials were highly recommended to withstand the higher temperature requirement especially for copper wire bonding process and 260oC lead-free reflow requirements. However, having such requirements coupled with the trend in package miniaturization, die attach adhesive modulus of elasticity comes into consideration. Thus, the objective of the study is to investigate the acceptable modulus of elasticity to resolve the issue on wire bonding process capability and/or workability. Per investigation, results showed the silicon die size dependency on the modulus of elasticity of the die attach adhesive. Depending on the modulus of elasticity values, corresponds to a minimum allowable die size to achieve acceptable process output response/s. An equation together with a predictive value were defined and verified to check its validity.|
|Alvin Denoyo, New Product Development Manager