Thermal and Cure Kinetics of Epoxy Molding Compounds Cured with Thermal Latency Accelerators

Chean-Cheng Su,Bo-Ching Li,Chien-Huan Wei

doi:10.1155/2013/391267

Chean-Cheng Su, Bo-Ching Li + Show 1 more

Open Access

https://doi.org/10.1155/2013/391267

Copy DOI

Abstract

The cure kinetics and mechanisms of a biphenyl type epoxy molding compounds (EMCs) with thermal latency organophosphine accelerators were studied using differential scanning calorimetry (DSC). Although the use of triphenylphosphine-1,4-benzoquinone (TPP-BQ) and triphenylphosphine (TPP) catalysts in biphenyl type EMCs exhibited autocatalytic mechanisms, thermal latency was higher in the TPP-BQ catalyst in EMCs than in the TPP catalyst in EMCs. Analyses of thermal characteristics indicated that TPP-BQ is inactive at low temperatures. At high temperatures, however, TPP-BQ increases the curing rate of EMC in dynamic and isothermal curing experiments. The reaction of EMCs with the TPP-BQ latent catalyst also had a higher temperature sensitivity compared to the reaction of EMCs with TPP catalyst. In resin transfer molding, EMCs containing the TPP-BQ thermal latency accelerator are least active at a low temperature. Consequently, EMCs have a low melt viscosity before gelation, and the resins and filler are evenly mixed in the kneading process. Additionally, flowability is increased before the EMCs form a network structure in the molding process. The proposed kinetic model adequately describes curing behavior in EMCs cured with two different organophosphine catalysts up to the rubber state in the progress of curing.

Highlights

In IC design, semiconducting chips have become larger, while devices have become smaller
A previous study found that TPP-BQ accelerated the reaction of epoxy molding compounds (EMCs) more than TPP did at high temperatures; in addition, EMCs containing TPP-BQ were relatively inert at a low temperature [20]
The acceleration in reaction time was larger in EMCS cured with TPP-BQ than in EMCS cured with TPP, and EMCs containing TPP-BQ were relatively inert at a low temperature

Summary

Introduction

In IC design, semiconducting chips have become larger, while devices have become smaller. New epoxy molding compounds (EMCs) for encapsulating microelectronic devices are needed in the near future because halogen-containing flame retardants and antimony oxide flame retardant synergists, which are widely used in present-day molding compounds, may be environmentally hazardous. In typical green molding compounds, flame retardants (e.g., phosphorus-containing compounds, nitrogen-containing compounds, metal hydrate, metal oxide, inorganic filler, and resins with high C/H ratios) have generally replaced the conventional halogen-containing flame retardants and antimony oxide flame retardants used in EMCs [1, 2]. EMC with biphenyl resins and highly loaded fillers can retard flammability and is a green material. To produce reliable packaging materials for microelectronic devices, a highly loaded filter with specific characteristics is needed: high flame retardation, high thermal resistance, high moisture resistance, favorable mechanical properties, and a low thermal expansion coefficient of EMC [3, 4]

Objectives

Findings

Discussion

Conclusion