Fundamental interconnect systems for connecting high-speed electronics elements are provided. The interconnect systems consists of the signal line, dielectric system with opened trench or slot filled up with the air or lower dielectric loss material, and the ground plane. The signal line could be for example, microstripline, strip line, coplanar line, single ended or differential pairs. The interconnect system can be used for on-chip interconnects or can also be used for off-chip interconnects (chip-to-chip interconnects). The fundamental techniques provided in this invention can also be used for high-speed connectors and high-speed cables. More over, this fundamental technology is also used for the high sped die package, high speed connector, and high speed cables where conventional manufacturing technology can be used and yet to increase the bandwidth of the interconnects.