Package Structure Carrier Edge Geometry to Prevent Dielectric Sagging

The patent applies preliminary action by forming an under layer on the carrier before forming the dielectric layer. This under layer is specifically designed to extend to the periphery edges and maintain structural support during subsequent processing steps, preventing the sagging that would otherwise occur with larger circuit layers. The under layer is prepared in advance to address the potential failure mode before it occurs during manufacturing.

The patent applies local quality by creating a flat portion at the periphery of the carrier where the under layer is formed to a different thickness than the main body. This localized structural modification provides enhanced support and control at the vulnerable periphery edges, while the main circuit layer area maintains its full functionality. The different thickness region specifically addresses the edge sagging problem without affecting the overall circuit performance.

The under layer is formed in advance on the carrier before the dielectric layer is applied. This preliminary structure provides a rigid foundation that prevents the dielectric layer from sagging during formation and subsequent processing. The under layer's extension to the periphery edges ensures that the dielectric layer maintains proper shape and coverage without experiencing the sagging that would lead to exposure and damage.

The under layer acts as an intermediary structure between the carrier and the dielectric layer. It provides mechanical support and structural stability to prevent dielectric layer sagging, while also serving as a foundation for the dielectric layer to be formed upon. This intermediate layer resolves the contradiction by enabling both edge coverage and shape maintenance simultaneously.

The under layer is formed on the carrier as a preliminary structure before the circuit layers are completed. This under layer maintains the release film's attachment to the carrier throughout the manufacturing process, preventing premature peeling. The under layer's structural support ensures that the release film remains stable even as the circuit layers are formed and processed, allowing complete circuit layer formation without early release film failure.

The under layer provides beforehand cushioning by creating a buffer structure that absorbs and distributes mechanical stresses during manufacturing. This cushioning effect prevents the release film from peeling off prematurely by providing structural reinforcement at the carrier interface, allowing the circuit layers to be fully formed without the release film failing early in the process.