The present invention provides a multi chip module which realizes high functions or high performances thereof. A multi chip module is constituted by stacking a first semiconductor chip on which a digital signal processing circuit is mounted, a second semiconductor chip which constitutes a dynamic random access memory, a third semiconductor chip which constitutes a non-volatile memory, and a mounting substrate thus forming the stacked structure. The first semiconductor chip is arranged on an uppermost layer with a spacer interposed on a back surface side thereof. The second semiconductor chip is arranged on the mounting substrate.