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Automotive LiDAR: Photonics assembly requirements

and trends

By Limin Zhou, Avy Yi [MRSI, a part of Mycronic Group]
I n this paper, the similarities and

differences between automotive
light detection and ranging
(LiDAR) and optical transceivers
are compared. The photonics device
assembly requirements and trends in
automotive LiDAR are introduced. From
the analysis, an assembly solution for
automotive LiDAR is explained. Finally, a
demonstration of the solution with actual
assembly experiments for typical edge-
emitting lasers (EELs) and vertical cavity
surface emitting laser (VCSEL) chips for
automotive LiDAR are presented.

Overview
Vehicular safety has always been very
important to the automotive industry—
and the situational awareness enabled
by advanced sensors plays a critical role
in building safe self-driving vehicles. Table 1: Automotive LiDAR vs. optical transceiver.
Most car makers believe LiDAR is
necessary and important for both control low-noise photodiodes, mode The quality system of the LiDAR
advanced driving assistance systems converters, and optical waveguides, supplier has to pass the IATF 16949
(ADAS) and autonomous vehicles (AVs). etc. Table 1 shows the comparison of certification process. Additionally,
The demand for automotive LiDAR in automotive LiDAR and optical transceivers. automotive LiDAR has to pass the AEC-Q
ADAS applications is growing at a high Based on the table entries, automotive series reliability test, especially the higher
double-digit compound annual growth LiDAR is in an earlier phase of product life temperature operation reliability test.
rate (CAGR), and mass production of cycle than the optical transceiver. While the reliability of the photonics
automotive LiDAR is rapidly becoming a From Table 1, we know automotive chips/dies must be high enough to ensure
reality. Driven by new technologies and LiDAR does not have industry standards the final products meeting the AEC-Q
economies of scale, automotive LiDARs for packages and optoelectronics (OE) reliability requirements, the chip assembly
are becoming lighter, thinner, and cheaper. interfaces at this point in time. The solution must also meet the same reliability
The high-reliability assembly of photonics end users of automotive LiDAR have standard. Laser chips and their assembly
devices is the key challenge for the mass diverse package design requirements are the most critical factors in determining
production of highly-reliable automotive to fit it into their cars. This means the reliability of the LiDAR system. High-
LiDAR. To address this challenge, it is that the vehicle manufacturers decide reliability laser chip assembly can enable
necessary to understand the assembly on the package form and interface of the high-reliability automotive LiDAR
needs and technology trends of automotive automotive LiDAR devices. If a LiDAR volume manufacturing to meet IATF
LiDAR, and then provide the best supplier targets multiple vehicle models 16949 zero defect requirements. To that
photonics device assembly solution. from multiple car companies, there will end, advanced equipment and processes
be a wide range of package form factors. are needed.
Photonics devices assembly in Manufacturing in the automotive LiDAR Wit h t he a dva nce me nt of new
automotive LiDAR industry, therefore, will be high-mix technologies, we find that automotive
Automotive LiDAR is a complex low-volume for the time being. As a LiDAR imaging technology has evolved
photonics sensor system that consists of result, LiDAR suppliers have to provide from mechanically-scanned LiDAR to
multiple optical components, including flexible equipment to support different hybrid solid-state LiDAR, and then to
lasers, amplifiers, phase and amplitude- customers’ packaging and assembly solid-state LiDAR. The packaging of
process designs. automotive LiDAR evolved from discrete

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