Aisen Stock (688720.SH) has achieved a significant milestone in China’s quest for semiconductor self-sufficiency by securing its first commercial orders for self-developed low-temperature Photosensitive Polyimide (PSPI). This development marks a rare breach in the decades-long monopoly held by a handful of international specialty chemical giants, primarily from Japan and the United States. As global demand for high-performance computing surges, the ability to produce high-purity electronic chemicals domestically has become a strategic priority for Beijing.
Low-temperature PSPI is a vital dielectric and insulating material used in advanced semiconductor packaging, including 2.5D and 3D architectures. It serves as the bedrock for Redistribution Layers (RDL) and Through-Silicon Via (TSV) passivation, which are essential for connecting multiple chips in a single package. By operating at lower curing temperatures, Aisen’s material protects sensitive components from thermal stress, a critical requirement for the sophisticated fan-out wafer-level packaging used in modern AI accelerators.
For years, the semiconductor material sector has been a chokepoint for Chinese manufacturers, as the synthesis of polyimides with high photosensitivity and thermal stability requires immense R&D investment and specialized expertise. Aisen’s transition from development to commercial orders suggests that Chinese firms are successfully navigating the steep learning curves associated with high-end lithography and packaging chemicals. This success aligns with national efforts to insulate the domestic chip industry from potential export controls on foundational materials.
The timing of this breakthrough is particularly relevant as the industry pivots toward "More than Moore" strategies, where packaging innovation replaces traditional node shrinking as the primary driver of performance. With AI giants demanding increasingly complex chiplet-based designs, the domestic availability of PSPI could provide Chinese OSATs (Outsourced Semiconductor Assembly and Test) with a more resilient and cost-effective supply chain. While Aisen still faces the challenge of scaling production to meet global standards, this order signals a shift from experimental capability to market readiness.