302
S. Lee
Table 10.9 DOE2: mechanical process parameters
Leg
Stage
temp
(°C)
Contact
temp (°C)
Dwell time
at peak
temp
305 °C (s)
Head
release
temp (°C)
Bond
force
(N)
Melting
detection
(μm)
Yield
(%)
1
130
130
5
130
2.8
6
80 > (Open)
2
130
130
5
130
2.8
8
80 > (Open)
3
130
130
5
130
2.8
10
100
Fig. 10.48 Comparison of
micro bump die nominal
joint heights: (a) melting
detection of 6 μm and
(b) 10 μm using DOE2 [18]
Only a melt detection setting of 10 μm yielded a nominal joint height of about
32 μm without any opens or bridges. Figure 10.14 shows a comparison of the nominal
MBD interconnect heights when a melt setting was used of 6 um and 10 μm. For the
6 μm melt setting a nominal joint height of 42.6 μm was achieved, and for a 10 um
melt setting a nominal joint height of 31.8 μm was achieved (Fig. 10.48).
10.5 Special Topic: Comprehensive Comparative Analysis
of Microstructure of Sn–Ag–Cu (SAC) Solder Joints
by Traditional Reflow and Thermo-Compression
Bonding (TCB) Processes
10.5.1 Introduction
“The adoption of 3D HBM modules continues to grow as there is an increasing
demand for high-performance consumer electronic devices [33]. Therefore, the needs
for these devices require modules for finer pitch, which brings an attention to the
TCB-processed interconnects with copper-posts and copper-pillars. Currently, the