Delivering On-chip Bandwidth Off-chip and Out-of-box with Proximity and Optical Communication
While copper-based electrical Serdes links have, to date, dominated the domain of ultra-short reach interconnects, future high-performance computers may require the integration of diverse interconnect technologies. In previous chapters, various forms of proximity communication that can provide low-energy chip-to-chip links between adjacent chips have been described. The strengths of proximity communication lie in low-energy short-distance links; the strengths of optical communication lie in efficiently reaching longer distances. Here we look to combine these technologies in a new hybrid I/O platform that can deliver balanced bandwidth on-chip, off the chip and even out of the box. In this chapter we will introduce the concepts of an optical-to-proximity interface chip, and review results from an experimental 90 nm test chip that integrates three types of high-speed chip-to-chip interconnects: capacitive interconnects for proximity communication; optical interconnects employing vertical-cavity surface-emitting lasers (VCSELs) and photodiodes; and electrical interconnects using current-mode logic (CML). We will discuss the operation and compatibility of each interconnect modality, and review interface requirements, chip layout considerations and test results.
KeywordsOptical Communication Optical Link Test Chip Optical Interconnect IEEE Photonic Technology Letter
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- 4.A.V. Krishnamoorthy, K.W. Goossen, “Progress in Optoelectronic-VLSI smart pixel technology based on GaAs/AlGaAs MQW modulators,” International Journal of Optoelectronics, vol. 11, no. 3, 1997, pp. 181–198.Google Scholar
- 5.L.M.F. Chirovsky, A.V. Krishnamoorthy, W.S. Hobson, J. Lopata, L.A. D’Asaro, “Verticalcavity surface-emitting lasers specifically designed for integration with electronic circuits,” Heterogeneous Optoelectronics Integration, SPIE Critical Review, Vol. CR76, 2000, pp. 49–74.Google Scholar
- 6.A.V. Krishnamoorthy, L.M.F. Chirovsky, W.S. Hobson, R.E. Leibenguth, S.P. Hui, G.J. Zydzik, K.W. Goosen, J.D. Wynn, B.J. Tseng, J. Lopata, J.A. Walker, J.E. Cunningham, L.A. D’Asaro, “Vertical-cavity surface emitting lasers flip-chip bonded to gigabit/s CMOS circuits,” Photonics Technology Letters, vol. 11, no. 1, 1999, pp. 128–130.CrossRefGoogle Scholar
- 7.F.E. Doany, C. Schow, C. Baks, R. Budd, Y.-J. Chang, P. Pepeljugoski, L. Schares, D. Kuchta, R. John, J. Kash, F. Libsch, R. Dangel, F. Horst, B. Offrein, “160-Gb/s Bidirectional Parallel Optical Transceiver Module for Board-Level Interconnects Using a Single-Chip CMOS IC,” Proceedings of the 57th Electronic Components and Technology Conference, vol. 57, 2007, pp. 1256–1261.Google Scholar
- 9.A.V. Krishnamoorthy, “The intimate integration of photonics and electronics,” Advances in Information Optics and Photonics ICO Vol. VI, SPIE Press, 2008, pp. 589–607.Google Scholar
- 11.A.V. Krishnamoorthy, J.E. Ford, F.E. Kiamilev, R.G. Rozier, S. Hunsche, K.W. Goosen, B. Tseng, J.A. Walker, J.E. Cnningham, W.Y. Jan, M.S. Nuss, “The Amoeba switch: an optoelectronic switch for multiprocessor networking using dense-WDM” IEEE Journal of Selected Topics in Quantum Electronics, vol. 5, no. 2, 1999, pp. 261–275.CrossRefGoogle Scholar
- 13.C. Cook, J.E. Cunningham, A. Hargrove, G.G. Ger, K.W. Goossen, W.Y. Jan, H.H. Kim, R. Krause, M. Manges, M. Morrissey, M. Perinpanayagam, A. Persaud, G.J. Shevchuk, V. Sinyansky, A.V. Krishnamoorthy, “A 36-channel transceiver parallel optical interconnect module based on optoelectronics-on-VLSI technology,” IEEE Journal of Selected Topics in Quantum Electronics, vol. 9, no. 2, 2003, pp. 387–399.CrossRefGoogle Scholar
- 15.J.K. Lexau, X. Zheng, J. Bergey, A.V. Krishnamoorthy, R. Ho, R. Drost, J.E. Cunningham, “CMOS integration of capacitive, optical, and electrical interconnects,” Proceedings of the International Interconnect Technology Conference, 2007, pp. 78–80.Google Scholar