On May 22, 2025, Nippon Electric Glass (NEG) announced the development of large Through-Glass Via (TGV) glass core substrates compatible with next-generation semiconductor packaging. The new substrates are designed for two processing methods: laser modification followed by wet etching, and direct CO₂ laser processing.

For the laser modification/etching-compatible type, NEG has begun offering samples, including both processed 515×510 mm substrates with TGVs and unprocessed glass sheets. This laser-based process first alters the glass structure to form a modified zone, which is then selectively etched using chemicals to create fine vias—enabling high-precision microvias.

TGVs are fine through-holes formed in glass substrates, primarily used for electrical interconnections in core substrates.

Background and Motivation

As AI advances and data centers expand, demand for high-performance and high-density semiconductor packaging has surged. In particular, chiplet technology—which integrates multiple smaller chips into a single package—has driven the need for larger, high-flatness, highly insulating, and rigid inorganic core substrates.

In response, NEG has focused on developing advanced inorganic glass materials. The company previously introduced its proprietary GC Core, a glass-ceramic core substrate with CO₂ laser-drilled vias, which received strong market interest.

As demand also grows for laser modification and wet etching-based TGV processing, NEG began developing compatible glass materials in 2020. The latest effort includes a newly formulated glass optimized for this process and an expanded capability to provide large-size TGV substrates as samples.

Outlook

NEG continues to push forward with CO₂ laser-compatible inorganic core substrates announced in 2024, aiming for mass production by 2028. With the launch of these new laser-modification-compatible substrates, the company seeks to strengthen its presence in the inorganic core substrate market through expanded customer evaluations.

Nippon Electric Glass Co., Ltd., headquartered in Ōtsu, Shiga Prefecture, is one of the world's leading manufacturers of specialty glass. Its advanced glass technologies support a wide range of applications—from semiconductors and displays to automotive, electronics, medical, and energy sectors. Backed by over 70 years of experience, NEG's innovations in specialty glass continue to be highly regarded across both everyday life and cutting-edge industries.