Staff Mechanical Engineer

Milpitas, CA, Superconductor - Tool Development, Full-time, On-site Commonwealth Fusion Systems is on a mission to deliver the urgent transition to fusion energy. Combining decades of research, top talent, and new technologies, we’re designing and building commercially viable fusion power plants and working with policymakers and suppliers to build the energy industry of the future. Staff Mechanical Engineer We’re looking for a Staff Mechanical Engineer to join our R&D and equipment design team to help build the next generation of thin-film deposition technology. As the “Second Chair” within our engineering group, you will be a high-impact technical leader who solves complex, semi-ambiguous problems that influence the success of multiple teams. What You'll Do Own System Execution: Drive the design, integration, and validation of advanced R&D equipment for thin-film processing, taking independent ownership of long-term projects and major mechanical sub-systems. Act as Technical Lead & Responsible Engineer (RE): Provide technical leadership on complex, cross-functional projects, lead small project groups and serve as a discipline-specific advisor. Solve Highly Complex Problems: Address ambiguous technical challenges impacting multiple groups, proactively remove project barriers and generate novel solutions. Plan & Organize Milestones: Generate detailed work plans and milestones for complex and semi-ambiguous hardware developments. Standardize Best Practices & Policies: Drive continuous process improvement, tool development, and department policies using semiconductor standards as guidance. Manage Project Risk: Independently manage medium risks, identify larger system risks, and drive the development of robust mitigation solutions. Collaborate & Influence: Build strong relationships across departments, effectively communicate highly complex concepts to diverse audiences and resolve cross-functional conflicts to achieve alignment. Mentor Talent: Actively mentor junior colleagues, taking direct ownership of their technical growth and skill development. Deliver with Speed: Translate system-level requirements into innovative concepts, driving projects efficiently from design through assembly, testing, and implementation. What We’re Looking For Education: Master’s degree in Mechanical Engineering or a related field (or equivalent industrial experience) Experience: 10+ years of experience in designing and implementing complex R&D systems or semiconductor manufacturing equipment Domain Expertise: Expert-level mastery of core mechanical engineering functions with a deep technical focus on thin-film processing hardware or vacuum systems Autonomy & Judgment: Proven ability to operate independently with near-complete autonomy, making sound judgment calls that impact major project components Thermal & Structural Expertise: Proven capability in high-temperature structural design and complex thermal management within vacuum environments Vacuum System Proficiency: Deep understanding of vacuum architecture, including material outgassing, seal integrity, and pump-down optimization Software Mastery: Expertise in 3D modeling (SolidWorks and/or NX) and familiarity with FEA/Thermal simulation tools (COMSOL, ANSYS) Hands-on Capability: Ability to bridge the gap between design and the shop floor, including experience with manual/CNC machining, prototyping, and hardware troubleshooting Vendor Management: Experience selecting and qualifying global vendors for specialized components or custom sub-systems Bonus Points For Semiconductor Background: Prior success building first-of- kind or experimental tools for semiconducto Standards Knowledge: Familiarity with applying SEMI, ASME, ASTM, and other industry-standard mechanical codes to hardware designs Motion Control: Experience designing precision motion and motor-controlled systems within challenging environments Must-have Requirements Ability to occasionally lift up to 50 lbs Perform activities such as stooping, climbing, standing, or sitting for extended periods of time Dedication to safety to mitigate industrial hazards that may include heat, cold, noise, fumes, strong magnets, lead (Pb), high voltage, and cryogenics Willingness to travel or work required nights/weekends/on-call occasionally Compensation & Benefits Salary: $130,000 - $200,000 per year plus equity and benefits. The range reflects new hire salaries for the position across all U.S. locations. Benefits include: Competitive compensation with equity 13 company-wide holidays Flexible vacation days 10 sick days Generous parental leave policy Health, dental, and vision insurance 401(k) with employer matching Professional growth opportunities Team-building activities We value diversity deeply and are proud to be an equal-opportunity employer by choice. All qualified applicants are considered equally regardless of race, color, national origin, ancestry, citizenship status, protected veteran status, religion, physical or mental disability, marital status, sex, sexual orientation, gender identity or expression, age, or any other basis protected by law. This role requires compliance with U.S. laws concerning the export of controlled or protected technologies or information (“Export Control Laws”). Any offer of employment will be contingent on the need for compliance with such Export Control Laws. #J-18808-Ljbffr Gigascale Capital