hc34_nharris_lightmatter (3).pdf

1、12 2InvestorsGV(Google Ventures)Spark CapitalMatrix PartnersViking GlobalHewlett-Packard EnterpriseMassachusetts Institute of TechnologyStanford UniversityBostonMountain ViewEnvisePassageIdiom3 3Lets talk about silicon photonics.4SILICON HANDLEBOXSILICON DEV LAYERGERMANIUM400 nm200 nm300mm CMOS Fab5

2、127 m127 mInterconnect density per waveguide layer.OPTICAL FIBERNANOPHOTONIC WAVEGUIDESA Sense of ScaleOptical fibers versus nanophotonic waveguides6What does silicon photonics look like?PHOTODETECTORRING MODULATORGRATING COUPLERY-JUNCTIONWAVEGUIDE CROSSINGSILICON HANDLEBOX10m7Why bring optics close

3、r to the SoC?-Disaggregation-Data closer to compute-PCB trace losses too high for long,high-speed links-SoC die sizes maxd out,cant accomodate large#s of LR SerDes-Reduction in interconnect power-Increased bandwidth over pluggables-Higher bandwidth density at die edge-Bypass intermediate stages(PCIe

4、)Enabling new communications technologiesCloser and closer to the chipGen IPluggable OpticsGen IIOn-board OpticsGen III2.5D Co-packaged OpticsGen IV3D Co-packaged OpticsGen V3D Co-packaged Optics with Integrated LasersOptical LinksElectrical LinksPluggable Optical TransceiverOn-board Optics ModuleDi

5、saggregated Laser SupplyCo-packaged PIC8Challenges at chip and system level with co-packaged optics.9Optical Fiber AttachExpensive,low throughput10XPU(850mm2)Max Fiber Count2003.6 cm2.4 cmOptical Fiber Beachfront DensityFibers are massive1.0 mm11100 TbpsCHIPLET BISECTION BANDWIDTH100 Tbps+1 pJ/bit+1

6、 pJ/bit+1 pJ/bit+1 pJ/bit3.2 Tbps3.2 TbpsCHIPLET XPU&CPO1 Tbps1 Tbps1 Tbps1 TbpsMORE HOPS,MORE ENERGYBeachfront and bandwidth are fundamentally linked in chiplet processors.Big chips are at odds with high yield.Each chiplet hop adds to communications energy consumption.Building large chiplet arrays