Optical interconnects: a viable solution for interconnection beyond 10 gbit/sec

ABSTRACT

The speed and complexity of integrated circuits are increasing rapidly as integrated circuit technology advances from very-large-scale integrated (VLSI) circuits to ultra-large-scale integrated (ULSI) circuits. As the number of devices per chip, the number of chips per board, the modulation speed, and the degree of integration continue to increase, electrical interconnects are facing their fundamental bottlenecks, such as speed, packaging, fan-out, and power dissipation. In the quest for high-density packaging of electronic circuits, the construction of multichip modules (MCM), which decrease the surface area by removing package walls between chips, improved signal integrity by shortening interconnection distances and removing impedance problems and capacitances. The employment of copper and materials with lower dielectric constant materials can release the bottleneck in a chip level for the next several years. The International Technology Roadmap for Semiconductors (ITRS) expects that on-chip local clock speed will constantly increase to 10 GHz by the year 2011. Electrical interconnects operating at a high-frequency region have many problems to be solved, such as crosstalk, impedance matching, power dissipation, skew, and packing density. Optical interconnection has several advantages, such as immunity to the electromagnetic interference, independency to impedance mismatch, less power consumption, and high-speed operation. Although the optical interconnects have great advantages compared with the copper/low K interconnection, they still have some difficulties regarding packaging, multilayer technology, signal tapping, and reworkability. In this presentation, the progress of optical interconnect for intra and inter-board levels will be presented with both passive and active components suitable for system integration including thin film planar waveguides, vertical cavity surface emitting lasers (VCSELs), PIN photodiode array and silicon nano-photonic crystal waveguide modulators.

REFERENCES

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INDEX TERMS

Primary Classification:
  J. Computer Applications
  J.2 PHYSICAL SCIENCES AND ENGINEERING
      Subjects: Electronics

General Terms:
Design, Experimentation

Keywords:
PCB interconnects, optical bus architecture, optical interconnects