ASYMMETRIC FRONT / BACK SOLDER MASK

摘要

A substrate including a die side interconnect pattern having a first solder mask thickness, and a board side interconnect pattern having a second solder mask thickness, where the second thickness is greater than the first thickness. Fabrication process using dry film solder mask can apply a first laminate thickness forming a die side solder mask, and a second laminate thickness forming a board side solder mask; the second thickness being greater than the first thickness. Fabrication process using a liquid solder resist can apply a first number of passes of solder resist forming a die side solder mask, and a second number of passes of solder resist forming a board side solder mask, where the board side thickness is greater than the die side thickness.