Work

A color-coded light-induced heating technology for Pb-free solder joints of advanced multi-semiconductor packaging

Year: 2025

Type: article

Abstract: The complexity of semiconductor packaging is increasing due to artificial intelligence, heterogeneous integration, and chiplet technology, necessitating precise thermal control in multi-component soldering. Conventional reflow soldering requires multiple heating cycles to accommodate different solder alloys, leading to process inefficiencies, excessive thermal exposure, and mechanical degradation. This study introduces a color-coded intense pulsed light (IPL) reflow process, leveraging differential light absorption for localized thermal modulation, enabling simultaneous soldering of multiple alloys in a single reflow cycle. The results show that IPL-soldered joints exhibit superior or comparable mechanical integrity to conventional reflow, with thinner, more stable intermetallic compound (IMC) layers, refined Ag 3 Sn precipitates, and reduced void formation, enhancing reliability. The rapid, transient heating of IPL suppresses excessive IMC growth while optimizing microstructural evolution. Substrate color engineering offers a scalable method for selective thermal regulation, positioning color-coded IPL as a high-efficiency, energy-conscious alternative for next-generation semiconductor packaging.

Source: Journal of Materials Research and Technology

DOI: 10.1016/j.jmrt.2025.11.166

Authors: Taejoon Noh, Ho-Gyeong Seong, Minjae Sung, Jaejun Yoon, Jong-Woong Kim, Seung-Boo Jung

Institution: Sungkyunkwan University

Language: English

Topic: Electronic Packaging and Soldering Technologies

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Industry, innovation and infrastructure

Open Access status: gold

Estimated APC paid: $1,640