山下マテリアル List of Products and Services

Button-plated flexible printed circuit boards (FPC) can utilize the original thickness and characteristics of copper foil by applying through-hole plating only to the through-holes and through-hole lands. This allows for uniform maintenance of conductor thickness, enabling the formation of high-precision wiring, which is expected to provide high-accuracy impedance control, making it ideal for high-speed transmission applications. Compared to conventional panel plating methods, button-plated FPCs excel in flexibility and bendability, achieving ultra-thin designs. This enables the lightweight and compact design of products. The new method also allows for button plating on narrow pitch patterns. Product Features: 1. By applying copper plating only to the through-holes, the original characteristics of the copper foil are maximized. 2. High-precision impedance control is possible, demonstrating performance suitable for high-speed transmission. 3. Compared to panel plating methods, it excels in flexibility and bendability while achieving ultra-thin designs. 4. It provides stable quality with technology that has cleared reliability evaluations based on JISC5016. 5. Through-hole plating is possible even for narrow pitch patterns, which were previously difficult to achieve.

The "Ultra-small diameter through hole" is a flexible substrate designed to have holes filled by 15μm through-hole plating. It is possible to form through holes with a diameter of 25μm or less on double-sided flexible substrates. Additionally, we also offer "4-layer filled blind vias," which allow for the filling of blind vias through plating on 4-layer flexible substrates. 【Specifications】 〈Ultra-small diameter through hole〉 ■ Base polyimide: 50μm ■ Conductor thickness: 12μm ■ Hole diameter (entry side): φ20μm ■ Hole diameter (exit side): φ15μm ■ Land diameter: 95μm *For more details, please refer to the PDF document or feel free to contact us.

"Ultra-small diameter through holes" are formed with a diameter of φ20μm on both sides of the FPC through laser processing. It is possible to create holes with a minimum diameter of 20μm and a minimum pad diameter of 95μm. By using through-hole plating to fill the holes and arranging the through holes on the pattern, it enables narrower pitch and contributes to the miniaturization of the product. 【Features】 ■ Formation of through holes with a diameter of Φ25μm or less on both sides of the FPC is possible. ■ The holes are filled with 15μm through-hole plating specifications. *For more details, please refer to the PDF document or feel free to contact us.

The "Ultra-Fine Circuit High-Frequency Flexible Substrate" is a flexible substrate designed for high-frequency applications in the GHz range, compatible with bare chip mounting. By using LCP (Liquid Crystal Polymer) with low dielectric properties as the core material and forming circuits using the SAP (Semi-Additive Process), it is possible to create transmission lines with a differential impedance of 100Ω at wiring pitches below 50μm. To accommodate wire bonding with bare chips, the mounting pads are treated with ENEPIG (Electroless Ni Pd Au plating) for surface treatment. One of the features of SAP is its high precision in circuit formation, with an accuracy of ±5μm, making it suitable for impedance control. *For more details, please download the PDF or contact us.*

By incorporating non-through filled vias into extremely small pads with narrow pitch, it becomes possible to implement electronic components at a higher density. This enables the miniaturization of flexible substrates and the implementation of multi-pin SoC chips. 【High-Density Implementation Possible】 It is possible to directly create filled vias on very small pads (φ100μm) with a pitch of 150μm, allowing for higher density component implementation. 【Easy Miniaturization】 Since high-density components can be implemented, it allows for the design of miniaturized substrates.