Composite IC die package including an electro-thermo-mechanical die (ETMD) with through substrate vias

A system comprising:

• a host component;
• an integrated circuit (IC) die package comprising:
• a first IC die with first interconnect interfaces on a first side of the first IC die;
• a passive die directly bonded to a first portion of the first side of the first IC die, wherein the passive die lacks a device layer, but comprises routing metallization coupled to second interconnect interfaces on a first side of the passive die, and one or more through vias extending from the routing metallization to corresponding third interconnect interfaces on a second side of the passive die, wherein the second interconnect interfaces are in direct contact with first ones of the first interconnect interfaces;
• and
• a second IC die adjacent to the passive die and directly bonded to a second portion of the first side of the first IC die, wherein the second IC die comprises fourth interconnect interfaces on a first side of the second IC die and in direct contact with second ones of the first interconnect interfaces, and wherein the second IC die comprises through vias extending to fifth interconnect interfaces on a second side of the second IC die;
• and
• solder features, wherein a first ones of the solder features are in contact with a first portion of the host component and in contact with the third interconnect interfaces, and wherein second ones of the solder features are in contact with a second portion of the host component and in contact with the fifth interconnect interfaces.