A low-cost (with bare chips) and high (optical, electrical, thermal, and mechanical) performance optoelectronic system embedded into a PCB (printed circuit board) or an organic laminated substrate is designed and described. This system consists of a rigid PCB (or a substrate) with an embedded optical polymer waveguide, an embedded vertical cavity surface emitted laser (VCSEL), an embedded driver chip, an embedded serializer, an embedded photo-diode detector, an embedded tans-impedance amplifier (TIA), an embedded deserializer, embedded heat slugs, and a heat spreader. The bare VCSEL, driver chip, and serializer chip are 3D stacked and then attached on one end of the embedded optical polymer waveguide in the PCB. Similarly, the bare photo-diode detector, TIA chip, and deserializer chip are 3D stacked and then attached on the other end of the embedded optical polymer waveguide in PCB. The back-side of the driver or serializer and the TIA or deserializer chips is attached to a heat slug with or w/o a spreader. This novel structural design offers potential solutions for low-cost and high-performance semiconductor circuits with optical devices to realize widebandwidth and low-profile optoelectronic packaging for chipto-chip optical interconnect applications. Optical, thermal management, and mechanical performances are demonstrated by simulations based on optic theory, heat-transfer theory, and continuum mechanics.(1) IntroductionThe major trend in the optoelectronic industry today is to make products more personal by making them smarter, lighter, smaller, thinner, shorter, and faster, while at the same time making them more friendly, functional, powerful, reliable, robust, innovative, creative, and economical [1, 2]. As the