Senior Photonics Test Engineer

Cspeed IO is a stealth start up backed by Sutter Hills Ventures and Atreides Capital - headquartered in Palo Alto, CA.  Our executive team has a demonstrated track record of building and scaling category-defining semiconductor and infrastructure businesses at companies like Broadcom, Lumentum, Tesla, Apple, Samsung, Intel, and VMware.

Cspeed IO is developing next-generation optical semiconductor solutions for the AI infrastructure market, focused on enabling true “scale-up” architectures.  Our mission is to replace traditional copper interconnects with advanced fiber-optic technologies that overcome the limitations of existing optics solutions and architectures.

Measurement quality and test coverage are critical to getting our laser and silicon photonic devices from design to production at scale. We are seeking a Senior Photonics Test Engineer to own test specifications and measurement quality for our laser and silicon photonics product lines — working in a fast-paced, cross-functional environment with high visibility into both device performance and production outcomes. The ideal candidate combines deep practical knowledge of optical and photonic measurements with the discipline and communication skills to operate independently, hold external vendors accountable, and ensure measurement results meet product standards.

Responsibilities

• Define and own test specifications; manage revision control and verify that vendor-implemented test programs accurately reflect documented requirements.
• Translate high-level test requirements from design engineers into concrete test implementations; coordinate execution with external test vendors and validate results.
• Analyze Gauge R&R (GR&R) data and lead structured troubleshooting of faulty or underperforming tests; propose modifications to improve cycle time, repeatability, and coverage.
• Oversee bring-up of specialty characterization tests; review first-pass measurement data and provide clear summaries to design teams.
• Facilitate and track software-based test troubleshooting with external vendors, ensuring compliance with specifications and driving timely resolution.
• Evaluate test infrastructure capabilities, identify gaps, and define standards for acceptable test coverage in collaboration with engineering stakeholders.
• Prepare and deliver clear technical reports and presentations; coordinate effectively across time zones with engineering and management teams.

Required Qualifications

• Industry experience in photonics or optical device testing, with demonstrated ownership of test specifications and measurement quality.
• Strong practical knowledge of LIV characterization, spectral measurements, optical power calibration, fiber coupling, and identification of measurement artifacts.
• Solid understanding of single-mode and multimode fiber-coupled measurement setups, including fiber selection, alignment, and coupling efficiency optimization.
• Familiarity with standard photonics test instrumentation: OSAs, precision current sources, power meters, integrating spheres, temperature-controlled stages, and TEC controllers.
• Coding literacy sufficient to review automated test programs, communicate precisely on software-driven test issues, and facilitate debugging with external vendors; SCPI/VISA familiarity is a practical signal.
• Working knowledge of measurement uncertainty and GR&R/MSA methodology in a production or engineering validation environment.

Preferred Qualifications

• Experience with automated fiber alignment systems for photonic or optical testing.
• Hands-on experience working with external test vendors or contract manufacturers.
• Background in III-V laser devices, silicon photonics, or related compound semiconductor technologies.
• Experience in R&D or research-grade optical characterization environments.

Education

Bachelor's degree in Electrical Engineering, Optics, Applied Physics, or a closely related field with a curriculum that includes optical measurements, photonics, or instrumentation. Master's degree is a plus.