New MCM composed of D/L base substrate, high-density-wiring CSP and 3D memory modules

Abstract

A RISC (reduced instruction set computer) module, which contains secondary cache memories and is called an MCM for use in a high-performance workstation has been developed. The design consists of a D/L (deposited organic thin film on laminated printed-circuit board) base substrate, a glass-ceramic-based organic-thin-film multilayer build-up CSP (chip size package), and glass-ceramic 3-dimensional memory (3DM) modules. The characteristics of this newly developed MCM are as follows. The D/L base substrate has 179 I/O (input/output) pins and signal lines of 25-/spl mu/m width and 50-/spl mu/m pitch. The CSP carrier signal lines are as fine as those of the D/L, and the CSP carrier features 525 I/O pads and 80-/spl mu/m diameter chip bonding pads with 108-/spl mu/m pitch. The 3DM is almost the same size as a conventional single chip mold package; with the stacking of ten memory chips in the space of four 3DMs, the area required is roughly only that of four single chip packages.