HDI PCB has the following technical requirements in production:
1. The conductor width and insulation spacing are less than 50um, the dielectric thickness is less than 50um, and the micropore diameter is less than 75um.
2. Product characteristics exceed the current ipc 2226 level c standard.
3. During the production process, it is necessary to use a variety of via hole type combinations, such as buried vias, blind vias, and through holes. At the same time, fine routing and spacing are required, as well as short interconnect traces.
4. In the design of high-density interconnection circuit boards, it is necessary to use closely spaced passive components (even buried passive components or passive substrates), and coreless structures (a very new concept).
5. Multi-level structure is also an important feature of HDI PCB, it is not a single thickness.
These technical requirements make HDI PCB production highly difficult and complex, requiring strict quality control and process management.