Intermediate substrate

An intermediate substrate comprising:

• a substrate core comprising a main core body portion constructed of a sheet of polymer material and including a subsidiary core accommodation portion opening at a first main surface of the main core body portion so as to reduce the overall transverse thickness thereof in the region of said subsidiary core accommodation portion, and a subsidiary core portion, constructed of a material having a smaller linear expansion coefficient than said main core body portion, accommodated in said subsidiary core accommodation portion and having a thickness which, together with the transverse thickness of any remaining portion of said main core body portion in said region, matches the overall transverse thickness of said main core body portion;
• a first terminal array formed on a first main surface side of said substrate core and comprising first side first terminals and first side second terminals some of which function as power terminals and others of which function as ground terminals, said first terminal array further comprising first side signal terminals;
• and
• a second terminal array formed on a second main surface side of said substrate core and comprising second side first terminals and second side second terminals which are conductively connected to said first side first terminals and said first side second terminals, respectively, and second side signal terminals conductively connected to said first side signal terminals;
• said first terminal array being disposed at a position overlapping a resultant projected area of said subsidiary core portion produced by geometric projection of said subsidiary core portion orthogonally onto a reference plane parallel to a planar face of said substrate core, and said intermediate substrate further comprising, accommodated in said subsidiary core portion, a multilayered capacitor, comprising, in order, a first conductive electrode layer, a dielectric layer and a second conductive electrode layer, and conductively connected to said first side second terminals and said second side second terminals.

An intermediate substrate comprising:

• a substrate core comprising a main core body portion constructed of a sheet of polymer material and including subsidiary core accommodation portion opening at a first main surface of the main core body portion so as to reduce the overall transverse thickness thereof in the region of said subsidiary core accommodation portion, and a subsidiary core portion, constructed of material having a coefficient of linear expansion smaller than that of said main core body portion, accommodated in said subsidiary core accommodation portion and of a thickness which, together with the transverse thickness of any remaining portion of said main core body portion in said region, matches the overall transverse thickness of said main core body portion;
• a first terminal array formed on a first main surface of said substrate core and comprising first side first terminals and first side second terminals functioning as power terminals and ground terminals, respectively, and first side signal terminals;
• and
• a second terminal array formed on a second main surface of said substrate core and comprising second side first terminals and second side second terminals, conductively connected to said first side first terminals and said first side second terminals, and second side signal terminals conductively connected to said first side signal terminals;
• said first terminal array being positioned entirely within a projected area of said subsidiary core portion geometrically projected orthogonally into a reference plane parallel to a planar face of said substrate core
• and said substrate further comprising a multilayered capacitor, comprising first and second conductive electrode layers separated by a dielectric layer, conductively connected to said first side second terminal and said second side second terminals and accommodated in said subsidiary core accommodation portion.