Senior Thin-film Materials Engineer (inorganic)

We are looking for a Senior Thin-film Materials Engineer to develop and own the inorganic material stack at the heart of Rivercell's platform. You will combine materials science, deposition-process engineering, device physics, and reliability to develop the photoconductor, dielectric layers, and their interfaces as one integrated system. Your objective will be to achieve strong optical switching, reliable high-field operation, and a reproducible fabrication process.

You will work hand-in-hand with our microfluidic chip lead, surface scientist, characterization engineer, and assembly team, as well as an interdisciplinary team spanning genetic engineering, AI and software, bio-laboratory automation, optics, electronics, and biology. You will be an integral part of an ambitious and exciting startup project from its inception.

Develop and optimize a-Si:H and evaluate alternative photoconductive materials, together with dielectric layers and multilayers based on SiNₓ, SiO₂, Al₂O₃, and related materials Translate chip-level requirements into specifications for conductivity, ON/OFF ratio, spectral response, capacitance, leakage, breakdown strength, optical transmission, stress, uniformity, and lifetime Optimize photoconductor properties including dark and illuminated conductivity, response time, absorption, defect density, hydrogen incorporation, thickness, stress, and long-term stability

Develop and tune PECVD, ALD, sputtering, or related deposition processes for composition, stoichiometry, density, hydrogen content, roughness, thickness uniformity, and process repeatability Engineer interfaces between the transparent electrode, photoconductor, dielectric stack, and upper surface while minimizing plasma damage, thermal degradation, interfacial defects, and delamination

Design multilayer architectures that balance voltage distribution, photoconductor switching, capacitance, optical performance, dielectric strength, charge injection, charge trapping, and manufacturability Plan and execute structured development campaigns with internal laboratories, external cleanrooms, research partners, and equipment vendors Characterize and interpret electrical, optical, and structural measurements, including impedance, leakage, breakdown, FTIR, ellipsometry, profilometry, and spectroscopy

Investigate failure modes such as excessive dark current, insufficient photoconductivity, non-uniform switching, dielectric leakage, breakdown, charge drift, hydrogen loss, stress, pinholes, and process-induced damage Define process windows, test structures, material specifications, acceptance criteria, and the roadmap for transfer to scalable fabrication equipment Opportunity to work on a cutting-edge project in the field of biotech Opportunity to join an ambitious team and impactful startup among the first employees Competitive salary and equity package Exciting opportunities for personal and professional growth within the team

a PhD in materials science, applied physics, semiconductor engineering, electrical engineering, microelectronics, or a related field.

• You have 5+ years of relevant experience developing semiconductor and/or dielectric thin films, including hands-on deposition, characterization, and process optimization.
• You understand how material properties, interfaces, process conditions, and electrical fields interact at device level.
• You combine scientific curiosity with an engineering mindset focused on reproducibility, specifications, reliability, and practical execution.
• You are autonomous, committed, enthusiastic, and comfortable working with a can-do, creative, and challenging mindset.
• You are rigorous in experiment design, documentation, data interpretation, and communication of uncertainty.
• You have excellent communication skills and are fluent in English; professional proficiency in French is helpful but not required.
• You have previous experience in one or more of the following areas: PECVD, ALD, sputtering, PVD, or related thin-film deposition processes Amorphous semiconductors, dielectric materials, defect states, carrier transport, charge injection, and charge trapping Electrical, optical, and structural characterization of multilayer thin-film devices Cleanroom process development, design of experiments, process transfer, or work with external fabrication partners Integration of multilayer stacks in microelectronic, photovoltaic, display, MEMS, sensor, or optoelectronic devices Please let us know in your application if you specifically have experience with one or several of the following: Hydrogenated amorphous silicon, TFTs, thin-film photovoltaics, image sensors, photodetectors, or related devices SiNₓ, SiO₂, Al₂O₃, oxide–nitride multilayers, or high-field dielectric reliability FTIR, ellipsometry, impedance spectroscopy, C–V, leakage-current, breakdown, or bias-stress measurements Charge-trapping, dielectric ageing, breakdown statistics, or lifetime modelling Large-area uniformity, thick-film deposition, and transfer of recipes between research and industrial tools

Throughout the recruiting process, you will meet 4 to 6 team members of Rivercell. Introductory call (up to 30mn, videocall) Technical interview (up to 90mn) Performance interview (up to 90mn, in person) Culture interview (up to 60mn, in person)