ADVANCED BORON NITRIDE EPOXY FORMULATIONS EXCEL IN THERMAL MANAGEMENT APPLICATIONS
Published: |
October 14, 2020 |
Author: |
Michael J. Hodgin and Richard H. Estes |
Abstract: |
Epoxy based adhesives are prevalent interface materials for all levels of electronic packaging. One reason for their widespread success is their ability to accept fillers. Fillers allow the adhesive formulator to tailor the electrical and thermal properties of a given epoxy. Silver flake allow the adhesive to be both electrically conductive and thermally conductive. For potting applications, heat sinking, and general encapsulation where high electrical isolation is required, aluminum oxide has been the filler of choice. Today, advanced Boron Nitride filled epoxies challenge alternative thermal interface materials like silicones, greases, tapes, or pads. The paper discusses key attributes for designing and formulating advanced thermally conductive epoxies. Comparisons to other common fillers used in packaging are made. The filler size, shape and distribution, as well as concentration in the resin, will determine the adhesive viscosity and rheology. Correlation's between Thermal Resistance calculations and adhesive viscosity are made. Examples are shown that determination of thermal conductivity values in "bulk" form, do not translate into actual package thermal resistance. Four commercially available thermally conductive adhesives were obtained for the study. Adhesives were screened by shear strength measurements, Thermal Cycling ( -55 °C to 125 °C ) Resistance, and damp heat ( 85 °C / 85 %RH ) resistance. The results indicate that low modulus Boron Nitride filled epoxies are superior in formulation and design. Careful selection of stress relief agents, filler morphology, and concentration levels are critical choices the skilled formulator must make. The advantages and limitations of each are discussed and demonstrated.... |
You must be a registered user to talk back to us. |
Company Information:
More SMT / PCB assembly technical articles »
- Apr 11, 2022 - iNEMI Webinar 07.07.2021 - PCB Cleaning | ZESTRON Americas
- Jan 28, 2022 - Open Radio Unit White Box 5G | Whizz Systems
- Nov 10, 2021 - Understanding the Cleaning Process for Automatic Stencil Printers | ITW EAE
- Oct 20, 2021 - PCB Surface Finishes & The Cleaning Process - A Compatibility Study | ZESTRON Americas
- Oct 06, 2021 - Cleaning Before Conformal Coating | ZESTRON Americas
- Browse Technical Library »
ADVANCED BORON NITRIDE EPOXY FORMULATIONS EXCEL IN THERMAL MANAGEMENT APPLICATIONS article has been viewed 250 times