PURPOSE: To provide a highly functional multichip module on which chips can be mounted at a high density.

CONSTITUTION: A multichip module is constituted by forming a mounting substrate of a solid glass substrate 1 having a cubic or rectangular parallelepiped shape and mounting such active components as LSI bare chips and other passive components 3 on all the surfaces of the substrate 1 except one surface used for connecting the substrate 1 to a main substrate.