The subject disclosure relates to 3D microelectronic chip packages with embedded coolant channels. The disclosed 3D microelectronic chip packages provide a complete and practical mechanism for introducing cooling channels within the 3D chip stack while maintaining the electrical connection through the chip stack. According to an embodiment, a microelectronic package is provided that comprises a first silicon chip comprising first coolant channels interspersed between first thru-silicon-vias (TSVs). The microelectronic chip package further comprises a silicon cap attached to a first surface of the first silicon chip, the silicon cap comprising second TSVs that connect to the first TSVs. A second silicon chip comprising second coolant channels can further be attached to the silicon cap via interconnects formed between a first surface of the second silicon chip and the silicon cap, wherein the interconnects connect to the second TSVs.