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Figure 2: MRSI-H-LD die bonding machine features.

fly” tool change for the multi-die process.
The bonder also has multiple die bonding
process capabilities and supports eutectic
bonding, epoxy stamping and dispensing,
UV curing, and flip-chip bonding.

Experiments
The laser chip assembly process is the
most critical step that affects the reliability
of automotive LiDAR assembly. The
experiments we performed involved the
selection of two typical laser chips that are
used for automotive LiDAR applications.
One is the 905nm EEL high-power laser
chip and the other is the 905nm high-
density multi-junction VCSEL chip.
For the 905nm EEL high-power laser
chip bonding, both eutectic and epoxy
processes are used in automotive LiDAR
depending on the laser package design. We
completed experiments for eutectic bonding
and had the following results: 1) Both X/
Y post-bonding accuracy measurements
are 2.7μm@3σ and the angle accuracy is
0.13°@3σ; and 2) For the epoxy process
experiment, the post-bonding accuracy
for X/Y is 2.8μm@3σ/3.0μm@3σ,
respectively, and the angle accuracy is
0.27°@3σ. Figure 3 shows the 905nm EEL
high-power laser die bonding results for the
eutectic and epoxy processes.
Typically, for 905nm high-density
multi-junction VCSEL chip bonding,

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