Xunlin nabs $30M Series B as glass substrate track heats up

Tianjin Xunlin Technology, a Chinese glass substrate maker, has raised nearly 200 million yuan (about $30 million) in a Series B round. New backers Inno Fund, Qiancheng Capital, Hymson, Prolight, and Tongxin Capital led the deal, while existing shareholders Jinyu Maowu, Haitong Kaiyuan, and Beishan Industrial Investment increased their investment.

Xunlin will spend the funds on glass substrate capacity expansion, packaging production line construction, process precision R&D, and optical communication applications. Its substrates target display, high-speed communication, advanced packaging, and CPO co-packaged optics.

The round lands amid a supply crisis for organic substrates. Electronic-grade fiberglass fabric prices have doubled from their 2025 low, FR-4 copper clad laminate has jumped more than 270%, and some AI packaging substrates now face delivery times beyond six months.

Organic substrates are hitting physical limits on thermal expansion, high-frequency loss, and wiring density as chip packages grow and optical module rates climb. Glass substrates offer an alternative — and this is Xunlin's third financing round in six months, a marker of its mass production progress.

The industry's biggest players are already moving. Intel says its Glass Core Substrate has entered large-scale mass production, TSMC's CoPoS trial line is due online in 2026, and Samsung and SKC Absolics are preparing samples. The capital now flowing to smaller players like Xunlin — whose raise ranks among the more sizeable in its cohort — suggests glass substrates are shifting from the lab to the center of the packaging market.