Senior Development Engineer – Photonic Devices / VCSEL Epitaxy (m/f/d)

Google Chrome Microsoft Edge Apple Safari Mozilla Firefox Senior Development Engineer – Photonic Devices / VCSEL Epitaxy (m/f/d)Full-timeBusiness Function: R&D EngineeringWork Location: Germany-Ulm-LMS13 Office--LOC_WDT_DEU-LMS13 OfficeCompany DescriptionWD is building the infrastructure behind the AI-driven data economy.As AI scales, so does data. Every interaction, every model, every system generates data that must be stored, managed, and made accessible over time. That’s where we come in.We combine deep engineering expertise with global-scale manufacturing to deliver the storage systems that make AI possible, powering hyperscale data centers, cloud platforms, and enterprise infrastructure worldwide.This isn’t theoretical work. It’s real systems, at real scale, people solving some of the hardest challenges in technology today.We’re looking for people who want to build, solve, and operate at that level.Join us and let’s shape the future of data.Job DescriptionThe Senior Development Engineer will drive the design and optimization of epitaxial stacks for VCSEL and related photonic device structures. The role focuses on translating device‑level requirements into robust epitaxial designs, using advanced semiconductor physics and numerical simulations to guide development and optimize performance, yield, and reliability. This position is ideal for someone with a strong academic and/or R&D background in semiconductor physics and photonic devices who wants to work at the interface of epitaxy, device design, and product development. Key ResponsibilitiesDesign and simulate epitaxial layer stacks for VCSEL and other photonic device structures to meet optical, electrical, and thermal device requirements.Develop and refine device and epitaxy simulation models (e.g., optical cavity / mode simulations, carrier transport, thermal behavior) to support architecture decisions.Translate system and device requirements into epitaxial specifications (materials, layer sequences, thicknesses, doping profiles).Work closely with epitaxy, process, and device characterization teams to:Define experiments and DOEs. Interpret measurement and reliability data. Iterate designs based on feedback from wafer- and device‑level results.Contribute to device architecture and development strategies, including roadmaps for performance, reliability, and manufacturability improvements.Analyze and correlate simulation, epitaxial, and device performance data to identify root causes and optimization paths.Prepare and present technical reports, design reviews, and development status updates for internal stakeholders.Collaborate in a multi‑disciplinary, international R&D environment, coordinating with colleagues across different locations and time zones (with substantial overlap to EU working hours).Mentor junior engineers and students in topics such as semiconductor device physics, simulation methodology, and data analysis.QualificationsPhD in Materials Science, Physics, Electrical Engineering, or a closely related field.Extensive professional experience with a strong record of sustained impact and increasing responsibility in R&D or applied academic research, ideally including collaboration with industry partners or participation in translational initiatives.Solid track record in semiconductor devices, preferably in photonic devices such as lasers, LEDs, or VCSELs.Deep understanding of semiconductor physics, including:Heterostructures and quantum wells. Optical cavities and resonant structures. Carrier transport, recombination mechanisms, and thermal effects.Experience with device or epitaxial stack simulations, for example:Optical mode / cavity simulations. Electronic band structure and carrier confinement. Thermal / electro‑thermal simulations.Strong ability to interpret experimental data (e.g., I‑V, L‑I, spectral, far‑field, lifetime/reliability data) and connect results to physical mechanisms and design choices.Fluent English (spoken and written),...