Substrate-Like PCB. SLP is called the "next generation of PCB". The L/S of SLP can be as low as 20/35um, compared to 40/50um of HDI. SLP is closer to IC substrate used for semiconductor packaging in manufacturing process.
The mSAP process can produce extremely detailed circuits, between HDI and IC carrier board.
Thinner and smaller size, suites the compact design for new-generation consumer electronics.
Good reliability, meeting the requirements of high-end customers.