An 
optoelectronics chip-to-
chip interconnects 
system is provided, including at least one packaged 
chip to be connected on the printed-circuit-board with at least one other packaged chip, optical-electrical (O-E) conversion mean, 
waveguide-board, and (PCB). Single to multiple chips interconnects can be interconnected provided using the technique disclosed in this invention. The packaged chip includes 
semiconductor die and its 
package based on the ball-grid array or chip-scale-
package. The O-E board includes the 
optoelectronics components and multiple 
electrical contacts on both sides of the O-E substrate. The 
waveguide board includes the 
electrical conductor transferring the 
signal from O-E board to PCB and the flex optical 
waveguide easily stackable onto the PCB to guide optical 
signal from one chip-to-other chip. Alternatively, the 
electrode can be directly connected to the PCB instead of including in the waveguide board. The chip-to-chip interconnections 
system is pin-free and compatible with the PCB. The main advantages of this invention are to use the packaged chip for 
interconnection and the conventional PCB technology can be used for 
low speed electrical 
signal connection. Also, the part of the heat from the packaged chip can be transmitted to the PCB through the conductors, so that complex cooling 
system can be avoided.