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shows the razor blade test on a silicon- 2020, pp. 41.3.1-41.3.4, doi: 10.1109/ temporary adhesives for wafer bonding
to-glass configuration with a measured IEDM13553.2020.9372005. applications,” MRS Online Proc.
crack length of 17mm. The corresponding 3. A. Elsherbini, S. Liff, J. Swan, Library Archive 970, doi: 10.1557/
bond strength was determined using the K. Jun, S. Tiagaraj, G. Pasdast, PROC-0970-Y04-09
2
Maszara model to be >2.5J/m , which is “Hybrid bonding interconnect for 6. G. Gao, G. Fountain, P. Enquist, C.
greater than the bulk fracture strength advanced heterogeneously integrated Uzoh, L.F. Wang, S. McGrath, et al.,
of silicon. These results indicate the processors,” IEEE 71st Elec. “Direct Bond Interconnect (DBI®)
PS PBM has the strong bond strength Comp. and Tech. Conf. (ECTC), technology as an alternative to thermal
required for hybrid bonding and is better 2021, pp. 1014-1019, doi: 10.1109/ compression bonding,” IWLPC, Oct.
than bonding with inorganic silicon oxide ECTC32696.2021.00166. 2016.
or silicon carbon nitride as the dielectric 4. R. Trichur, T. Flaim, “Temporary 7. V. Chidambaram, P. Lianto, X. Wang,
2
(0.9-1.8Jm ) [7]. bonding and thin wafer handling G. See, N. Wiswell, M. Kawano,
strategies for semiconductor device “Dielectric materials characterization
Summary processing,” Chip Scale Review, Nov/ for hybrid bonding,” IEEE 71st ECTC,
This paper introduces a developmental Dec, 2015. 2021, pp. 426-431, doi: 10.1109/
photosensitive permanent bonding 5. R. Puligadda, S. Pillalamarri, W.B. ECTC32696.2021.00078.
material with features of a low dielectric Hong, C. Brubaker, M. Wimplinger,
constant and dissipation factor, superior S. Pargfrieder, “High-performance
thermal stability, and low processing and
curing temperatures.
The fine-pitch patterning capability of
the PS PBM is also shown, supporting its
use for dense die-to-die interconnection.
With proper design and control in metal
height, the PS PBM/Cu-Sn structure has
demonstrated a good wafer-level hybrid
bonding quality between metal-to-
metal and between polymer-to-polymer
interfaces without CMP processing for
surface planarization. The bond strength
for the PS PBM was then evaluated to
be stronger than using silicon oxide as
the dielectric. More evaluations such
as grinding, reliability, and electrical
performance for the hybrid bonded stack
with PS PBM will be conducted and
shared in the future.

References
1. C. C. Hu, M. F. Chen, W. C. Chiou, D.
C. H. Yu, “3D Multi-chip integration
with system on integrated chips
(SoIC™),” 2019 Symp. on VLSI Tech.,
2019, pp. T20-T21, doi: 10.23919/
VLSIT.2019.8776486.
2. Y-K. Cheng, et al., “Next-generation
design and technology co-optimization
(DTCO) of System on Integrated
Chips (SoIC™) for mobile and HPC
applications,” 2020 IEEE Inter.
Electron Devices Mtg. (IEDM),

Biographies
Baron Huang is a Scientist Team Leader at Brewer Science, Inc., Rolla, MO. He has 14 years experience in
product development with a current focus on permanent bonding material and IC packaging polymer dielectric.
He has a MS in Chemistry from National Cheng Kung U. Email: bhuang@brewerscience.com
Mei Dong is is a Senior Research Associate of Wafer-Level Packaging - R&D Team at Brewer Science, Inc.,
Rolla, MO. She received her BS in Chemistry from Nankai U. and PhD in Chemistry with a focus on Polymer
Science from Texas A&M U.

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