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Title: Heterogeneous Integration for Silicon Photonic Systems: Challenges and Approaches
Enhancing the functionality of silicon through the integration of other materials such as III-V semiconductors has been recognized as a path to overcoming limitations imposed by characteristics fundamental to silicon's material physics while still capitalizing on properties that have enabled the success of the global integrated circuit industry [1]–[2][3]. High-speed electronic devices, devices with high breakdown voltages, light emitting/detecting devices, and devices for photon control can all be integrated with conventional CMOS to perform specialized electronic or photonic functions if suitable methods for forming such heterogeneously integrated regions are available that provide high yield and are compatible with fabrication processes that occur subsequent to the heterogeneous integration process. Technical challenges include lattice mismatch, thermal expansion coefficient differences, having the capability to form low-resistance electrical contacts using materials that are compatible with CMOS, more generally managing cross-contamination in tools used for front-end-of-line processing after III-V regions are established on the silicon wafers, and thermal management for the heterogeneously integrated devices or circuits. These together create formidable obstacles, but there is also the obstacle of defining a business case for creating hybrid wafer fabs given the applications that would be served by ICs with enhanced functionality. Bringing functions that are off chip onto the chip needs to be justified both technically and financially.  more » « less
Award ID(s):
1640196
PAR ID:
10277312
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
2021 5th IEEE Electron Devices Technology & Manufacturing Conference (EDTM)
Page Range / eLocation ID:
1 to 3
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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