PCBA Manufacturing Engineer

Flex is the diversified manufacturing partner of choice that helps market-leading brands design, build and deliver innovative products that improve the world.

A career at Flex offers the opportunity to make a difference and invest in your growth in a respectful, inclusive, and collaborative environment. If you are excited about a role but don't meet every bullet point, we encourage you to apply and join us to create the extraordinary.

Job Summary

To support our extraordinary teams who build great products and contribute to our growth, we’re looking to add a PCBAManufacturing Engineer located in Milpitas, CA.Reporting to the Director, Operations Engineering, the PCBA Manufacturing Engineer will play a critical role in the development, industrialization, and optimization of advanced PCBA manufacturing processes supporting next-generation AI, rack-scale computing, and data center applications. This position is part of a cross-functional team (CFT) responsible for building and scaling complex printed circuit board assemblies at the Milpitas campus.

The ideal candidate will possess hands-on experience across the complete SMT manufacturing process, including pick-and-place, reflow soldering, wave soldering, process validation, and yield improvement. This role requires a strong understanding of PCBA chemistry, mechanical interactions, manufacturing design considerations, and advanced packaging technologies, including large BGA components utilized in high-performance AI infrastructure. This position aligns with the core responsibilities of Manufacturing Engineering as defined within the Flex Production Engineering organization.

What a typical day looks like:

Drive and optimize the end-to-end PCBA manufacturing process, including solder paste printing, pick-and-place, reflow, wave soldering, inspection, and final assembly for AI, rack-scale computing, and data center products.

Lead NPI builds and production readiness activities while partnering with Design, Quality, Test, Supply Chain, and Operations teams to ensure manufacturability, yield, reliability, and scalable production.

Provide technical expertise for complex PCBAs featuring large BGA devices, supporting process development, thermal profiling, defect reduction, DFM/DFA reviews, and assembly optimization.

Troubleshoot manufacturing, process, and product-related issues using structured root cause analysis and implement corrective and preventive actions to improve quality and throughput.

Develop and maintain manufacturing documentation, including work instructions, process specifications, PFMEAs, control plans, validation reports, and process control strategies.

Analyze manufacturing data and lead continuous improvement initiatives focused on yield enhancement, cycle-time reduction, cost optimization, equipment efficiency, and overall operational excellence.

The experience we’re looking to add to our team:

Bachelor's degree in Manufacturing Engineering, Mechanical Engineering, Materials Engineering, Electrical Engineering, or a related technical discipline.
3-5 years of hands-on experience in PCBA manufacturing, with strong knowledge of the complete SMT process including solder paste printing, pick-and-place, reflow soldering, wave soldering, AOI, SPI, X-ray inspection, and process optimization for high-volume production.

Experience supporting complex PCBAs featuring large BGAs, high-density assemblies, and advanced packaging technologies, with the ability to troubleshoot manufacturing defects such as voiding, head-in-pillow, bridging, warpage, insufficient solder, and BGA-related failures.

Strong understanding of PCBA materials, solder chemistry, thermal management, mechanical interactions, and reliability considerations that impact assembly…