Sains Malaysiana 43(1)(2014): 117–122
Reflow
Soldering Process for Sn3.5Ag Solder on ENIG Using
Rapid Thermal
Processing
System
(Proses Pematerian Aliran
Semula bagi Pateri Jenis Sn3.5Ag di atas ENIG Menggunakan
Sistem Pemprosesan Terma
Pantas)
NOR ADHILA
MUHAMMAD1*, BADARIAH
BAIS1& IBRAHIM AHMAD2
1Department of Electrical, Electronic and
System Engineering, Faculty of Engineering
and Built Environment, Universiti
Kebangsaan Malaysia, 43600 UKM Bangi, Selangor
Malaysia
2Department of Electronics and Communication,
College of Engineering UNITEN,
Jln IKRAM-UNITEN, 43000 Kajang, Selangor,
Malaysia
Diserahkan: 15 Oktober 2012/Diterima: 17
April 2013
ABSTRACT
A study on reflow soldering process
for Sn3.5Ag solder on ENIG substrate was performed using the
rapid thermal processing (RTP) system. The reflow soldering
process by RTP system can be successful, but it is sensitive to some
typical defects. A poor RTP system design can lead to
significant temperature differences where non-uniform heating or cooling may
result in material failure due to increase in thermal stresses or serious
damage. From this study, it was found that at a peak temperature (Tpeak)
of 251°C, the reflowed solder was observed to be smooth joint appearance over
the solder pad and formed a regular joint shape of the solder due to the
efficient reflow profile and sufficient heating input during the reflow
process. The Ni3Sn4 intermetallic
compounds were found to be continuous, thus resulting in a good metallurgical
bonding between Sn3.5Ag solder and ENIG substrate. Meanwhile, an
uneven reflowed solder and defect mechanism was detected at Tpeak of
246 and 260°C. This is due to the inadequate reflow profile and insufficient
heating input during the reflow soldering process in the RTP system.
Visual micrographs of reflowed solder and cross-sectional micrograph and
elemental analysis were presented in this paper for better understanding of the
defect mechanism in order to optimize the reflow soldering process using RTP system.
The reflow soldering process can be performed better with appropriate reflow
profile in the RTP system in order to achieve a good
solder joint of Sn3.5Ag solder and ENIG substrate.
Keywords: Cross-sectional
micrographs; elemental analysis; reflow profile; soldering defects
ABSTRAK
Kajian berkenaan proses pematerian
aliran semula ke atas pateri jenis Sn3.5Ag di atas substrat ENIG telah
dijalankan menggunakan sistem pemprosesan terma pantas (RTP).
Proses pematerian aliran semula menggunakan sistem RTP boleh
dilaksanakan dengan jayanya tetapi ia sensitif kepada kecacatan
tipikal. Reka bentuk sistem RTP yang lemah akan menyumbang kepada perbezaan suhu yang
signifikan dengan pemanasan atau penyejukan yang tidak seragam akan
memberi kesan kepada kegagalan bahan disebabkan oleh peningkatan
tekanan terma atau kerosakan yang serius. Daripada kajian ini, pateri
yang telah mengalami proses pematerian aliran semula pada suhu puncak
251°C dikenal pasti mempunyai penyambungan yang licin pada pad
pateri dan menghasilkan bentuk penyambungan pateri yang baik hasil
daripada profil aliran semula yang lebih baik dan input pemanasan
yang mencukupi semasa proses aliran semula pematerian dilakukan.
Sebatian antara logam jenis Ni3Sn4
didapati berkeadaan selanjar lalu menghasilkan ikatan
metalurgi yang baik antara pateri jenis Sn3.5Ag dan substrat jenis
ENIG. Sementara itu, pematerian
yang tak seragam dan mekanisme kecacatan diperhatikan terhasil pada
pateri yang telah melalui proses aliran semula pematerian pada suhu
puncak 246 dan 260°C. Ini adalah disebabkan profil pematerian
aliran semula yang tidak memadai dan input pemanasan yang tidak
mencukupi semasa proses pematerian aliran semula di dalam sistem
RTP. Gambaran mikrograf pateri yang telah melalui proses
aliran semula pematerian dan mikrograf keratan rentas dan analisis
unsur bahan juga disampaikan di dalam kajian ini untuk lebih memahami
mekanisme kecacatan yang berlaku di samping dapat mengoptimumkan
proses pematerian aliran semula di dalam sistem RTP. Proses pematerian aliran semula dapat dijalankan dengan
baik menggunakan profil aliran yang sesuai di dalam sistem RTP
untuk mendapatkan penyambungan pateri antara pateri
jenis Sn3.5Ag dan substrat jenis ENIG
yang lebih baik.
Kata
kunci: Analisis unsur; kecacatan pematerian; mikrograf keratan rentas; profil
aliran semula
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*Corresponding author: email: adhila@sirim.my
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