Senior Development Engineer - Photonic Devices / VCSEL Epitaxy

The 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., * Design 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.

• PhD 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), with the ability to write clear technical documentation and present complex topics to a mixed audience.
• Ability and willingness to work at least partially in EU time zones to ensure effective collaboration with European teams.

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