3D-MAPS: 3D Massively Parallel Processor with Stacked Memory Dae Hyun Kim, Krit Athikulwongse, Michael Healy, Mohammad Hossain, Moongon Jung, et al. Georgia Institute of Technology, Atlanta, GA KAIST, Daejeon, Korea Amkor Technology, Seoul, Korea University of Tehran ISSCC 2012 Presented by: S.Ghanbari CIDSP Seminar May 2013 Major Reference:

Large Chip Area Long Interconnects Causing Delay-related Issues Hard to Meet Different Voltage Requirements 2D vs SoC vs 3D[7] 2-D Ics[7]: Inability of Using Incompatible Technologies Together

Solutions[7] 3D Packaging Stacking several chips in one package. Chips communicate using off-chip signaling. 3D Ics[7] Using different layers on the same chip. Chips communicate using on-chip signaling. 3D IC has the same relation with a 3D package as SoC with a Circuit board.

3D IC Advantages[7] Footprint Cost(yield and fabrication cost) Integrating different processes, better optimization Shorter interconnect Power reduction with On-chip signals Circuit security Bandwidth

Manufacturing Technologies[7] Wafer-on-Wafer Die-on-Die Die-on-Wafer Design styles[7] Gate-level Integration Block-level Integration

3D-MAPS 3D Massively Parallel Processor with Stacked Memory 64 general-purpose processor cores at 277MHz 256KB SRAM 130nm Technology 33M Transistors, 50K TSV, 50K Face-to-Face connections in 5mm*5mm footprint. 1.5V Supply, up to 4W power consumption. Results in 16W/cm2 power density.

3D-MAPS 3D Massively Parallel Processor with Stacked Memory 64 custom processor cores 4KB SRAM data memory for each core Theoretical maximum data memory bandwidth at 277MHz is 70.9GB/s Overview and single core architecture[1]

3D-MAPS Tezzaron 3D Technology F2F(Face to Face) bonding 235 I/O cells along the periphery of the core die. 204 TSVs, connecting metal 1 to backside metal, wirebonded to the package. Uses dummy TSVs to satisfy the TSV density rule(Total of 4500 dummy TSVs on the memory die).

3D-MAPS Stacking, TSV, F2F, and chip-to-package connection[1]

3D-MAPS Heat and Power measures 294 P/G land pads to supply high current(2.7A) hence high temperature(~90C from simulation). A dummy silicon substrate to increase thermal conductivity. Center region of LGA implemented as a large copper pad dedicated to VSS to decrease thermal resistance. Decoupling capacitors added to improve power integrity. Average parasitic values of signal package routes: R=377.5mΩL=4.1nHC=1pF

3D-MAPS Bandwidth and power measurement results[1]

3D-MAPS Frequency vs. power (at 1.5V) and voltage vs. power (at 250MHz) for AES encryption[1]

3D-MAPS Regularity Modularity Single core and memory tile layouts[1] Die photos[1]

[3] U. Kang, et al. “8Gb 3D DDR3 DRAM Using Through-Silicon-Via Technology”, ISSCC Dig. Tech. Papers,pp , References: [2] M. Koyanagi, et al. “Neuromorphic Vision Chip Fabricated Using Three-Dimensional Integration Technology”, ISSCC Dig. Tech. Papers, pp , [4] G. Van der Plas, et al., “Design Issues and Considerations for Low-Cost 3D TSV IC Technology”, ISSCC Dig. Tech. Papers,pp , [5J.-S. Kim, et al. “A 1.2V 12.8GB/s 2Gb Mobile Wide-I/O DRAM with 4x128 I/Os Using TSV-Based Stacking”, ISSCC Dig. Tech. Papers,pp , [6] M. Healy, et al. ”Design and Analysis of 3D-MAPS: A Many-Core 3D Processor with Stacked Memory”, IEEE Custom Integrated Circuits Conf., pp. 1-4, [7] [1] Dae Hyun Kim, Krit Athikulwongse, Michael Healy, Mohammad Hossain, Moongon Jung, et al. “3D-MAPS: 3D Massively Parallel Processor with Stacked Memory”, ISSCC 2012, S.10, P.06. " 3D-MAPS