Localization of Packaging Materials — The Domestic Story of Housings, Glass and Pastes

I. Why Is a "Small Materials Matter" a "Big Supply Chain Issue"?

The previous article covered LiDAR packaging; this one steps upstream — to the raw materials used in packaging.

A hermetic package may be small, but it relies on quite a few key materials: the alloy used for the housing, the glass used for insulators, and the metal pastes used for wiring inside ceramic packages. For a long time, high-end versions of these three material categories have been largely imported, sourced from a small handful of overseas suppliers.

The problem is that packaging factories' dependence on these materials is rigid — if import channels are disrupted, the impact falls not on a single company but on the entire downstream optical communication, automotive and sensor supply chains. In recent years, downstream customers have become increasingly explicit about "material autonomy and control", and domestic materials have thus entered an acceleration window.

II. How Far Have Domestic Materials Come?

Start with housing alloys. Domestic housing materials have advanced fastest of the three categories — in dimensional stability, thermal expansion behavior and machining precision, the gap with imported products has narrowed dramatically, and they can be confidently substituted in most applications.

Next, sealing glass. Glass must be "fired" together with the metal housing, and every step — sintering process, corrosion resistance — is a hurdle. After years of iteration, domestic glass has reached sealing strength essentially on par with imported products, with the gap now within single-digit percentages.

Finally, metal pastes. This category has long been monopolized by overseas suppliers and is the hardest to localize. Domestic pastes today already meet requirements in conventional ceramic packaging scenarios; only a few high-end applications still show a gap — and that is the next battlefield.

[Next Article] Next up: intelligent quality inspection — how AI helps packaging "spot the flaws".

[Glossary]

1. Kovar: an iron-nickel-cobalt alloy whose thermal expansion closely matches sealing glass, making it a common material for hermetic housings.

2. Sealing Glass: a specialty glass that insulates and seals between metal pins and housings, fusing with the metal as one body after high-temperature melting.