BOC(Board on Chip) refers to a CSP product used for DDR2. Since DDR2, we have been using the BGA, not the lead frame when performing DRAM packaging. The name, BOC, indicates that the chip is mounted backward, unlike the general BGA structure. In DDR2, the chip I/O is in the middle of the chip, unlike in general semiconductors, so the wire bonding area is also in the middle of the substrate. In DDR2, the traditional memory module packaging method, a lead type is not used, but instead, the BOC is used because we can reduce signal loss by reducing the space between the DRAM and the substrate.
-. PDA -. Wireless RF -. Memory (DDR SDRAM) -. Cell phone -. Workstation, Server, Video Camera -. Desktop PC, Note book PC
|Patterning||Line/Space||MSAP||25 / 25|
|Subtractive||35 / 35|
|Drilling||Via/Land||PTH||100 / 210|
|Slot Size Tolerance||± 100|
|Thickness||250 ± 30|