Optimizing Die Attach for Surgical LED Devices with Non-Cytotoxic Silver Epoxy

This case study is a collaboration between Master Bond and Nordson EFD.

Introduction

Dispensing a highly viscous, silver-filled epoxy onto a surgical LED device presents a nuanced engineering challenge: how to achieve precise, repeatable deposits without introducing voids, or compromising thermal and electrical performance.

A medical device manufacturer faced this exact problem when developing a die attach solution with stringent electrical, thermal, and biocompatibility requirements. In addition to delivering conductivity and heat dissipation, the material needed to maintain precise deposit geometry, cure at 125°C or below, and support a repeatable, automated dispensing process.

This application required close alignment between material properties and dispensing technology. The epoxy had to meet performance and regulatory standards, while the dispensing system needed to produce consistent, defect-free deposits without tailing, clogging, or air entrapment.

The resulting solution delivered highly repeatable dispensing, minimized process variation, and enabled reliable thermal management as well as electrical performance in production.

Application Requirements

The die attach adhesive needed to:

• Create and maintain electrical contact between the LED die and substrate
• Conduct heat away from the die to preserve LED output and service life
• Retain a thixotropic, paste-like shape without bleed-out onto adjacent pads
• Cure at or below 125°C to avoid damage to the LED
• Pass ISO 10993-5 for non-cytotoxicity
• Support repeatable, automated dispensing

Download now to learn more about how Nordson EFD and Master Bond optimized automated fluid dispensing and adhesive performance for a medical die attach application.

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