Molding compounds, epoxy

Kinjo, N., Ogata, M., Nishi, K. and Kaneda, A. Epoxy Molding Compounds as Encapsulation Materials for Microelectronic Devices. Vol. 88, pp. 1 —48. 

Epoxy-DICY systems, 10 454 Epoxy equivalent weight (EEW), 10 399 Epoxy ester alkyd resins, 2 165-166 Epoxy esters, 10 380-384, 443 Epoxy formulations, performance of, 10 428 Epoxy groups, 10 567 hydrolysis of, 10 358 acid-catalyzed cross-linking of, 15 171 Epoxy molding compounds (EMC), 10 373, 430 34, 458... 

To achieve low stress embedding material, low modulus material such as silicones (elastomers or gels) and polyurethanes are usually used. Soft-domain elastomeric particles are usually incorporated into the hard (high modulus) materials such as epoxies and polyimides to reduce the stress of embedding materials. With the addition of the perfect particle size, distribution, and loading of soft domain particles, low stress epoxy molding compounds have been developed as excellent embedding materials for electronic applications. 

Ishii, T., Kokaku, M., Nagsi, A., Nishita, T., and Kakimoto, M. 2006. Calcium borate flame retardation system for epoxy molding compound. Polym. Eng. Sci., 46(5), 799-806. 

Older fornulatione were much worse, and Figure 7 shows a comparison of the water-extractable halide after 200"C storage for four flame-retarded novolac epoxy mold compounds and an early nonflame-retarded variety. Several items are evident from this figure. 

H. Suzuki, T. Moriuchi, and M. Aizawa, Low Mold Stress Epoxy Molding Compounds for Semiconductor Encapsulation, Nitto Electric Industrial Co., Ltd., 1979. 

These resins (Resole or Novolac) are used as curing agents or hardeners for epoxy molding compounds for electronics applications such as computer components. 0-cresol-formaldehyde resins have heen also used to modify phenol-formaldehyde resins, and in laminates. 

Manzione, L. (1995) Processing epoxy molding compounds, in Thermoset Polymer Meeting for J. K Gillham s 60th birthday, Princeton, MA Princeton University. 

In this paper we examine moisture sorption in an epoxy molding compound formulation used for semiconductor encapsulation. In particular, we will be concerned with moisture uptake as a function of relative humidity. The effects of temperature, sample thickness, and processing history will be systematically examined for a single commercially important material. 

Thermal Stress in Epoxy Molding Compounds and Packaged Devices... 

Epoxy molding compounds, used to encapsulate microelectronic devices, contain bromine to provide flame retardancy to the package. This bromine, typically added as tetrabromo bisphenol-A or its epoxy derivative, has been found to contain many hydrolyzable bromides. These bromides, along with the presence of chloride impurities, are detrimental to the life of the electronic component. Bromine especially has been suspected (proven) to cause wire bond failure when subjected to moisture and/or high temperatures. With the addition of a more thermally and hydrolytic stable bromine compound, flame retardancy does not have to be compromised to increase the device reliability. Stable brominated cresol epoxy novolac, when formulated into a microelectronic encapsulant, increases the reliability of the device without sacrificing any of the beneficial properties of present-day molding compounds. 

Catalysts for Epoxy Molding Compounds in Microelectronic Encapsulation... 

The key to the development of the proper epoxy molding compounds for microelectronic encapsulation is the catalyst in the formulation. In spite of serious limitations in epoxy molding compound performance in sensitive microelectronic devices about ten years ago, the many new developments in catalysts during the last few years have enabled tremendous improvements. However, the exact curing mechanisms of various catalysts in epoxy molding compounds are still not fully understood today. 

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