Photonics Process Development Engineer

Great Sky is a technology startup based with a mission to rebuild AI from first principles. We are pursuing neuroscience-inspired hardware and algorithms that overcome the greatest challenges in scaling AI systems.

We are seeking a highly motivated Photonics Process Development Engineer to develop the cryogenic photonic networks central to our technology platform.

In this role, you will contribute to the design of SiN‑based passive photonic components and take full ownership of the R&D prototyping lifecycle. You will perform hands‑on device fabrication at a cleanroom facility located near our Boulder office.

This is a high‑ownership position with substantial influence on the pace and direction of our hardware development.

• Own end‑to‑end prototype fabrication runs in a research cleanroom environment.

• Develop, run, and optimize manufacturable fabrication processes for integrated photonic devices and superconducting devices, including SNSPDs.

• Develop and characterize unit processes, including electron‑beam and optical lithography, thin‑film deposition, dry etching, and planarization.

• Perform in‑line and post‑fabrication metrology (e.g., SEM, AFM, ellipsometry, profilometry) to control critical dimensions, film properties, and sidewall quality.

• Track yield, uniformity, and process variation, and lead root‑cause analysis of fabrication issues.

• Write standard operating procedures (SOPs) and turn process flows into stable Processes of Record (POR).

• Define and maintain the design rules and layer‑stack information that go into our internal Process Design Kits (PDKs).

• Work closely with design, test, packaging, and systems integration teams to correlate device performance with fabrication metrics, speeding up our design‑build‑test‑learn cycles.

• BS, MS, or PhD in physics, electrical engineering, optics, materials science, or a related field; or equivalent practical experience.

• Hands‑on experience in microfabrication, nanofabrication, or semiconductor processing.

• Experience fabricating devices on at least one of these platforms: silicon photonics, silicon nitride, or superconducting electronics.

• Hands‑on experience with core cleanroom processes such as e‑beam or optical lithography, thin‑film deposition (e.g., LPCVD, PECVD, sputtering), and reactive ion etching.

• Skill with process metrology and characterization tools (e.g., SEM, AFM, ellipsometry, profilometry).

• A track record of developing, documenting, and troubleshooting fabrication processes using data.

Preferred:

• Experience with SNSPD fabrication, including superconducting thin films (e.g., NbN, NbTiN, WSi).

• Experience with low‑loss SiN waveguide processing (e.g., thick LPCVD SiN, stress management, high‑temperature annealing, CMP).

• Experience with heterogeneous or hybrid integration methods such as bump bonding or fusion bonding.

• Experience transferring processes to external fabs or working with foundries.

• Familiarity with GDS tools (e.g., KLayout) for mask preparation and pattern data checks.

• Previous fabrication experience in shared, multi‑user facilities such as university clean rooms, national laboratories, or advanced commercial R&D centers.

• Meaningful equity ownership in an early‑stage deep tech company

• Employer‑matched 401(k)

• Health, dental, vision, and life insurance

• Flexible PTO

• Support for ongoing learning, conference attendance, and skill development

Our culture is onsite by default (we're founded by scientists who are used to working in the lab), with flexibility for hybrid arrangements. For the right person and role, we're open to filling roles remotely