In a semiconductor package stack module, an LSI (Large Scale Integrated circuit) is mounted, via fine bumps, on a ceramic carrier substrate or a flexible carrier film on which wiring conductors are formed. After a seal resin has been injected, the chip is thinned by, e.g., grinding. A plurality of such carrier substrates or carrier films are connected to each other by bumps via through holes which are electrically connected to the wiring conductors, thereby completing a tridimensional stack module. The module achieves a miniature, thin, dense, low cost, and reliable structure without resorting to a wire bonding system or a TAB (Tape Automated Bonding) system. In addition, the module has a minimum of wiring length and a desirable electric characteristic.