ABOUT LUMILENS At Lumilens we are building the critical photonics infrastructure that powers tomorrow’s AI supercomputing. From chip-to-chip optical interconnects to scalable photonic engines, Lumilens is unlocking a new era of computing faster, cooler, and massively more efficient. We’re a well-funded startup backed by Mayfield and led by veterans who’ve built and scaled some of the most transformative technologies in the industry. This isn’t incremental innovation, it’s a ground-floor opportunity to rethink the optical layer from the silicon up. You’ll work alongside a team of world-class engineers solving some of the hardest challenges in optics, systems, and scale. Every line of code, every design decision, every breakthrough you help deliver will shape the infrastructure of tomorrow. If you're looking for mission, momentum, and the chance to make an outsized impact jump on the rocket ship. We’re just getting started. Position Overview We are seeking a hands-on Component Process Engineer to serve as the primary substrate engineering interface between Lumilens’ hardware design teams, package manufacturing teams and worldwide substrate suppliers. This role focuses on FR4 substrate or PCB from new technology development, process development to qualification of the suppliers. The candidate must have solid hands-on experience in FR4 substrate/PCB product development, very familiar with mSAP/HDI/Any\_Layer manufacturing process. Engage with substrate/PCB design team during early development phase to provide DFM based on different PCB suppliers’ manufacturability. This position is ideal for an engineer who combines deep Material/Chemistry/Mechanical/Electrical knowledge with a passion for manufacturing process excellence, supplier development, and cross-functional execution at a global scale. Key Responsibilities • Identify, develop and qualify FR4/PCB substrate suppliers worldwide. • Lead DFM/DFT/DFR of PCB substrates, risk analysis and mitigation plan with suppliers. • Lead FR4/PCB quality control, failure analysis and reliability tests. • Engage with packaging production teams during the process development from SMT, die attach, wire bond, active alignment and testing. Required qualifications • B.S. or M.S. in Material, Chemistry or Mechanical Engineering. • 8+ years of working experience in FR4 substrate or PCB development or manufacturing, with in-depth knowledge in mSAP process, Any-Layer HDI process, for high-speed optical transceiver applications. Must be very familiar with all the equipment, typical materials and the typical process capabilities. • Familiar with PCB layout tools such as Cadence, mechanical design tools such as Solidworks, statistical tools such as JMP. • Working knowledge of PCB test methodologies. • Familiar with FMEA, Control Plan, SPC, 8D, etc. • Fluency in English to communicate with English speaking stakeholders. • 30~50% travel in Asian countries. Preferred qualifications • M.S. in Electrical or Manufacturing Engineering • Experience with optical transceiver manufacturing process such as SMT, die attach, wire bonding and active alignment. • Six Sigma, Statistical Analysis skills. What We Offer • Competitive salary and meaningful equity in a high-growth company • Comprehensive health, dental, and vision coverage