Integral passives for next generation of electronic packaging: application of epoxy/ceramic nanocomposites as integral capacitors

Abstract

The consumer demand for product miniaturization with increased functionality and reliability is ever growing in the electronic industry. Integral passive is a novel emerging technology which is perceived as a possible alternative to discretes in fulfilling the next generation of packaging needs. Although, integral passive technology has been proven to be a viable option, there are several barriers for implementing this technology such as efficient circuit design with increased component density, qualification of new materials for integral passive components and substrates, time-to-market a new product, technology transfer and product scale up toward commercialization, and most importantly cost competitiveness. Integration of passive components on substrates imposes a major design and fabrication challenge and has been a subject of increasing interest in the packaging community today. In this paper, we address materials and processes for integral capacitors and their co-integration with integral resistors and inductors. Dielectric constant values in the range of 3.5–50 with increase in filler loading up to 50vol% are achieved in the epoxy nanocomposite system where the dielectric constant of the host polymer is limited to ∼3.5. The capacitors are relatively stable up to a frequency range of 120Hz to 100kHz. Feasibility of integration of capacitor components has been demonstrated through fabrication of several industrial prototype circuits. Materials and process issues for passive elements such as resistors, capacitors, and inductors and the need for developing alternative substrate materials have also been addressed in this paper.