Advanced Packaging Engineer — Fiber Array Integration

CspeedIO is a stealth startup backed by Sutter Hill 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.

CspeedIO 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.

The Role

This position owns the detachable optical interface for CspeedIO optical engines: the on-package element, the coupling optics, the alignment features, and the high-volume assembly process that joins fiber to engine without per-unit active alignment.

Scope runs from interface architecture and tolerance budgeting through qualification and transfer of the production process to our assembly partners.

Responsibilities

Detachable interface architecture

• Define the location of the detachability point and the partition between the permanently attached on-package element and the mateable plug.
• Define the coupling optics for the detachable path, including expanded-beam or collimated design, lens prescription and tolerancing, and the surface- versus edge-coupling trade-off.
• Establish the alignment strategy — lithographically defined PIC features, precision mechanical datums, guide-pin or V-groove references — and the passive alignment capability it delivers.

Tolerance, loss, and repeatability budgeting

• Own the insertion loss budget, including mated-interface penalty, per-channel uniformity across the array, and return loss.
• Develop the tolerance stack from PIC feature placement through package assembly to plug geometry using statistical methods, with a per-port loss distribution as the deliverable.
• Specify and demonstrate repeatability across mate and demate cycles, and interchangeability across plug units and suppliers.
• Quantify positional and angular sensitivity and define the budget the mechanical design must hold.

High-volume manufacturing readiness

• Qualify reflow survivability of the on-package element and compatibility with the assembly flows our OSATs operate.
• Define automated mating requirements: insertion force, blind-mate behavior, retention, and hands-off assembly tooling.
• Establish Cpk on passive placement and coupling loss, with associated SPC limits, yield reporting, and failure taxonomy.
• Maintain the per-port cost and cycle-time model covering alignment, mating and cleaning time, rework, and connector BOM.

Contamination control and serviceability

• Define the contamination control strategy: dust caps, handling protocol, cleaning process and tooling, inspection criteria, and particle-size sensitivity for the selected beam geometry.
• Define serviceability requirements: authorized personnel, permitted mating cycles, required training and tooling, and diagnostic criteria distinguishing contamination from mechanical damage.
• Define the rework and RMA flow for the optical interface.

Reliability and qualification

• Qualify the mated interface.
• Characterize insertion loss drift across mating cycles and environmental exposure.
• Conduct root-cause analysis of degradation across coupling optics, alignment features, latch mechanics, and contamination.

Required Qualifications

• BS/MS/PhD in Optical Engineering, Mechanical Engineering, Physics, Materials Science, or equivalent practical experience.
• 6+ years in optical or photonic packaging or optical interconnect, including ownership of an optical interface taken from development into production or pilot production.
• Direct experience with fiber-optic connector technology: ferrules and guide-pin alignment, expanded-beam or lensed interfaces, and mate/demate qualification.
• Tolerance stack analysis and GD&T for sub-micron optical interfaces, including statistical rather than worst-case methods.
• Working knowledge of fiber-to-chip coupling physics: mode field matching, collimation and beam expansion, angular and lateral sensitivity, polarization effects, and return loss.
• Hands-on optical metrology: tunable sources, power meters, insertion and return loss measurement, and interferometric or confocal inspection of interfaces.
• Experience qualifying an optical interface against connector reliability standards.
• Willingness to work in both laboratory and production environments, and professional English across distributed sites and time zones.

Preferred Qualifications

• Detachable or pluggable optical interfaces for co-packaged optics, on-board optics, or mid-board optical modules.
• Passive alignment using lithographically defined features; wafer-level optics; micro-lens array design or integration.
• Reflow-survivable optical assemblies, including interfaces qualified through a 260 °C profile.
• Precision manufacturing processes for connector hardware: ferrule molding, precision metal stamping or forming, glass forming, or micro-machining.
• Lens design and tolerancing (Zemax, CODE V, or equivalent).
• Silicon photonics: surface and grating couplers, facet preparation, and PIC-side alignment feature definition.
• Particle and contamination control in optical assembly environments.
• Active alignment process development experience.