1.HDI PCB (1+N+1): This is the simplest HDI PCB design structure suitable for BGA with lower I/O counts. It has a fine line, microvias and registration technologies capable of 0.4 mm ball pitch, excellent mounting stability and reliability, and may contain copper filled via. It is a qualified material and surface treatment for a Lead-free process. Some of the examples include a Cell phone, UMPC, MP3 Player, PMP, GPS, Memory Card, etc.
2.HDI PCB (2+N+2): This is a moderate complex HDI design structure that contains 2 or more build-up of high-density interconnection layers which allow the conductors on any layer of the PCB to be interconnected freely with copper filled stacked microvias structures. These structures are commonly seen in challenging designs that demand high-level signal transmission performance. They are suitable for BGA with smaller ball pitches and higher I/O counts and can be used to increase routing density in a complicated design while maintaining a thin finished board thickness. Some of the examples include smartphones, PDA, game consoles, and portable video recording devices.
3.Any Layer HDI PCB: This is the most complex HDI PCB design structure where all the layers are high-density interconnection layers which allow the conductors on any layer of the PCB to be interconnected freely with copper filled stacked microvias structures. This structure provides a reliable interconnect solution for highly complex large pin-count devices, such as CPU and GPU chips utilized on handheld and mobile devices while producing superior electrical characteristics. Some of the examples include smartphones, ultra-mobile PC, MP3, GPS, Memory cards, and small electronic devices.
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