1. Laminated structure
2. Production process
Flexible board cutting → drilling → etching → AOI → pressing cover film → pressing → drilling → immersion copper and panel plating → outer layer etching (alkaline etching) → AOI → solder mask and characters → immersion gold → opening routing → mechanical depth control → electrical test → rigid board routing → flexible board routing → FQC → packaging
3. Manufacturing difficulties
HDI process, laser blind hole, electroplating hole filling, mixed pressure of NF PP and flow glue PP, laser-controlled deep opening.
4. Application areas:
This rigid-flex board is used in smart watches. It is a combination of rigid and flex structure of HDI. Since smart watches have a graphic display function and require relatively high transmission speed, the rigid-flex board with an HDI structure is a good choice. It can not only reduce the size, but also ensure faster transmission speed.
