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designed, no chloride ion was detected Summary 2. T. Yamada, M. Fukui, K. Terada,
in the new resin, while more than I n t h i s s t u d y, a new PI D wa s M. Harazono, C. Reynolds, J.
500ppm of chloride ion was included developed based on the mater ial Audet, et al., “Development of
in the conventional resin. Once the d e s i g n . T h e P I D h a s l o w C T E a low CTE chip-scale package,”
synthesis of the new resin without (35-45ppm/°C) and high resolution 63rd Ele c. Comp. a nd Te ch.
chloride ion was established, the new (down to 6µm), which is beneficial for Conf \. (ECTC), 2013, pp. 944-
resin was applied to the new PID multi-layer RDL formation. The PID 948.
formulation, and a BHAST reliability has high resistance to organic solvents 3. Y. Su z u k i, V. Su nd a r a m , R .
analysis was conducted. for f ine-pitch SAP, and no crack Tummala, M. Arendt, L. Seongku,
in the PID was formed by acetone H. Hichiri, et al., ”Embedded
Demonstration of BHAST reliability dipping. As a result, very fine Cu line trench redistribution layers (RDL)
Test coupons for BHAST analysis patterning of 2µm L/S was successfully by excimer laser ablation and
were L/S = 2/2µm comb-like Cu demonstrated. A new synthetic method surface planar processes,” 67th
patterns, and they were fabricated of acid modified acrylate resin with no IEEE ECTC, 2017, pp. 884-889.
on the f irst layer of the new PID chloride impurity was developed. The 4. Y. Suzuki, J. Brune, R. Senczuk,
by the same SAP processes as in new PID applies the new resin, and R. Pätzel, R. Furuya, F. Liu, et
the previous section. After the Cu BHAST evaluation showed more than al., “Demonst ration of 20μm
patterning, the second layer of the new 300 hours of electrical reliability with pitch micro-vias by excimer laser
PID was laminated on top by vacuum 2µm L/S and a 5µm thin PID layer. ablation in ultra-thin dry-film
lamination and cured to complete the The PID material has fine-patterning polymer dielectrics for multi-
test sample fabrication (Figure 9). capabi l it y, a s wel l a s exc el le nt layer RDL on glass interposers,”
Fabricated test coupons were applied reliability, therefore it is a highly 65th IEEE ECTC, 2015, pp. 922-
to the reliability testing with the beneficial dielectric material for high- 927.
following conditions: density packaging applications, such 5. Y. Otake, “Troubleshooting of
as FOWLP, FOPLP, and high-density p olyme r m at e rials,” Kogyo -
• P recond it ion i ng: 125°C/24h package substrates. Zairyo, 66 (8) Aug. 2018.
⇒ 85°C/168h ⇒ Reflow 260°C/ 6. H. Kishi, T. Naitou, S. Matsuda,
3 times; and Acknowledgements A. Mu r a k a m i, Y. Mu r aji, Y.
• B H A S T: 13 0 ° C , 8 5 % @ 5 V T h e a u t ho r s w ou l d l i k e t o N a k a g a w a , “ R el a t io n s h i p s
(failure criteria : 1.0E+6 ohm) acknowledge the technical support between mechanical properties
from Research Center for Three- and nano-structures of DICY-
F o r a B H A S T c h a m b e r , a Dimensional Semiconductors, in cured epoxy resins,” J. of the
H A ST E ST ® M OD E L P C - R 8 D fabrication of test coupons for BHAST Adhesion Soc. of Japan 41(3), 84-
(Hirayama) was used, and for in situ evaluations. The authors also thank 92, 2005-03-01.
electrical resistance measurement, Mitsui Mining & Smelting Co., Ltd. 7. I. M. Barszczewska-Rybarek, A.
a MIGR ATION TESTER MODEL for its technical support in multi-layer Korytkowska-Walach, M. Kurcok,
MIG-8600B (IMV) was used. There RDL structure fabrication. G. Chladek, J. Kasperski,”DMA
was no migration or electrical failure analysis of the structure of cross-
after 300 hours of BHAST condition. References linked poly(methyl methacrylate)
The cross-section analysis was then 1. K. Yamanaka, K. Kobayashi, K. s,” Acta of Bioengineering and
conducted, and the X-ray scanning Hayashi, M. Fukui, “Materials, Biomechanics Vol. 19, No. 1,
electron microscope (X-SEM) images processes, and performance of 2017, pp. 47-53.
of 2µm L/S structures (Figure 10) also h ig h-w i r i ng densit y bu ildup
show no sign of Cu migration from the s u b s t r a t e w it h u lt r a lo w -
fine-pitch Cu wirings. Layer-to-layer coefficient of thermal expansion,”
BHAST reliability of a PID thickness Comp. and Packaging Tech., IEEE
of 5µm was also conducted and no Trans. on, vol. 33, pp. 453461,
failure after 300 hours was confirmed. 2010.

Biographies
Yuya Suzuki is a Marketing Manager of Taiyo America, a sister company of Taiyo Ink Mfg. Co., Ltd., San
Jose, CA. He has more than 10 years of experience in electronic materials for advanced IC packaging. Before
joining Taiyo Ink, he worked for Zeon Corporation, and the 3D Packaging Research Center at the Georgia
Institute of Technology. He has a PhD in Material Science from Georgia Institute of Technology. Email
YuyaS@Taiyo-America.com

Chihiro Funakoshi is an Engineer at Taiyo Ink Mfg. Co., Ltd., Saitama, Japan, where, since 1994, he has been
developing polymer-based products for IC packaging. He received BS and MS degrees in Chemistry from Toyo U., Japan. He
has authored more than 10 patents on polymer materials.

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