14 April 2022
CompoundTek and Voyant to establish high-volume silicon photonic wafer test
Singapore-based silicon photonic (SiPh) foundry services provider CompoundTek Pte Ltd has formed a strategic collaboration with light detection & ranging (LiDAR) solution provider Voyant Photonics of Long Island City, NY, USA to establish cost-effective high-volume SiPh wafer test for LiDAR designed specifically for automotive as well as other fast-growing applications such as robotics and drones.
Addressing the growing need for consistency and reliability for LiDAR products, the collaboration aims to use SiPh wafer test as a cost-effective method to identify known good die (KGD) through stringent testing at elevated temperature to meet global quality requirements for automotive and industrial applications. Wafer-level testing also allows LiDAR product companies like Voyant to have faster yield feedback to capture potential excursion in the fab earlier and to minimize the cost of yield dropouts in the later stages of the packaging process.
LiDAR remote sensing uses a pulsed laser to measure distances and to generate a precise, three-dimensional map of geographical locations. This is commonly used today in autonomous vehicles (AVs), drones and robots to enable obstacle detection, avoidance and safe navigation. SiPh technology is currently used for LiDAR products, and is leveraged on well-established silicon integrated circuit manufacturing processes which are cost effective and relatively easy to manufacture.
“CompoundTek is thrilled to be working with Voyant to provide a cost-effective test strategy that is capable of meeting stringent international standards,” says IGSS Ventures’ founder & group CEO Raj Kumar, who is also CompoundTek’s CEO. “The key to market-wide adoption of wafer-level SiPh test lies in the cost and efficiencies of the test. This is particularly true for LiDAR, where comprehensive testing is done to meet the highest quality requirements for its end application, specifically in the automotive industry.”
The integration of optical with electrical components on a single chip is creating multiple new challenges in wafer-level testing of SiPh devices as large volumes of optical, electrical and opto-electrical device-performance data are required through various stages of the product development life-cycles, from prototyping to qualification and subsequently into production. This is especially true for LiDAR, where it is used in automotive applications that demand a higher level of stringent quality and reliability requirements than usual consumer products. Stringent wafer testing for defects is necessary as the consequences of test escapes can be very costly, not to mention hazardous and detrimental to life as well as property.
Most companies have home-grown SiPh bench solutions, which are perhaps sufficient for small-scale engineering characterization during the initial design verification phase but inefficient for the high-throughput and low-cost test required for testing from risk production to the mass-production phase.
“The explosive growth of incorporating LiDAR in many applications requires us to test our SiPh chips in both timely and cost-efficient ways,” notes Voyant’s principal engineer Lawrence Tzuang. “A test platform that offers repeatable and reliable SiPh wafer-level electro-optical testing is critical to achieve this goal,” he adds. “Working with a partner such as CompoundTek, which has both the test expertise and the capacity, allows us to focus on chip architecture and design, leading to both improved quality control for the manufactured chips and identifying failures in the earlier assembly steps.”
An agnostics SiPh wafer test service provider with a cost-efficient wafer test solution is needed to address market gaps, including for the largest SiPh product companies who had to make do with modified testers and limited in-house capabilities. CompoundTek and Voyant say that their combined capabilities help the industry to drive down associated product costs and time from the product development cycle to mass manufacturing, and helps to accelerate the time to market.