Patent ID: 8395054

Claim:
A substrate for mounting a semiconductor element, comprising: a low-thermal-expansion substrate having a mounting region configured to mount a semiconductor element, the low-thermal-expansion substrate comprising: an inorganic insulating layer, a wiring layer provided in the inorganic insulating layer, and a plurality of mounting pads formed in the mounting region and electrically connected to said wiring layer, said plurality of mounting pads being configured to mount said semiconductor element; an organic substrate coupled to the low-thermal-expansion substrate, the organic substrate comprising: a core base material having an opening in which the low thermal expansion substrate is provided, an interlayer resin layer provided on the core base material and on a peripheral portion of the low thermal expansion substrate, said interlayer resin layer having a recess which exposes the mounting region of the low-thermal-expansion substrate and said plurality of mounting pads, and a conductive portion formed in the interlayer resin layer and extending to said peripheral portion of the low thermal expansion substrate, the conductive portion electrically connecting the wiring layer of the low-thermal-expansion substrate to a conductive circuit of the organic substrate.