Staff Mechanical Engineer

Onto Innovation•Budd Lake, NJ

2d•$115,200 - $172,800

About The Position

Onto Innovation is seeking a highly skilled Opto-Mechanical Engineer to design, develop, and support advanced optical-mechanical systems used in next-generation semiconductor metrology equipment. This role requires deep expertise in precision mechanics, optical alignment, and environmental stability for high-accuracy measurement systems operating at sub-micron or nanometer scales. The ideal candidate will collaborate cross-functionally with optical, electrical, and process engineers to deliver robust, high-performance systems supporting semiconductor inspection and metrology applications.

Requirements

Bachelor’s or Master’s degree in Mechanical Engineering, Optical Engineering, or related field.
7+ years of experience in opto-mechanical design, preferably in semiconductor, photonics, or precision instrumentation.
Strong understanding of optical systems, including imaging, laser systems, interferometry, or illumination design.
Proficiency with CAD tools (e.g., SolidWorks, Creo, NX).
Experience with FEA tools (e.g., ANSYS, COMSOL) for thermal and structural analysis.
Knowledge of precision manufacturing methods (CNC machining, EDM, additive, etc.).
Familiarity with GD&T and tolerance stack-ups.
Strong problem-solving and analytical thinking skills.
Attention to detail with a focus on precision and accuracy.
Ability to work in multidisciplinary teams.
Effective communication and documentation skills.
Hands-on mindset with a balance of theoretical and practical expertise.

Nice To Haves

Experience with semiconductor metrology or inspection equipment (e.g., scatterometry, CD-SEM, overlay metrology).
Understanding of vibration isolation, air-bearing stages, and ultra-stable structures.
Experience integrating optical components such as lenses, mirrors, beam splitters, and fiber systems.
Knowledge of cleanroom standards and contamination control.
Experience with alignment tools such as interferometers, autocollimators, and optical benches.

Responsibilities

Design precision opto-mechanical assemblies including lens mounts, mirror systems, stages, and structural components.
Develop mechanical architectures that ensure optical alignment stability under thermal, vibration, and environmental variations.
Perform tolerance analysis for optical systems, including sensitivity studies and error budgets.
Collaborate with optical engineers to integrate lasers, detectors, imaging systems, and illumination paths.
Support alignment strategies and develop fixturing and tooling for assembly and calibration.
Ensure mechanical designs meet optical performance requirements such as wavefront error, distortion, and stability.
Conduct FEA (thermal, structural, modal) to evaluate deformation, drift, and vibration effects on optical performance.
Perform thermal management design to minimize drift and ensure repeatability in metrology measurements.
Analyze and mitigate sources of noise, including mechanical vibration and thermal expansion.
Build and test prototypes; troubleshoot alignment and performance issues.
Develop test procedures and validation methods for optical-mechanical subsystems.
Work closely with manufacturing to transition designs from prototype to production.
Partner with manufacturing, supply chain, and quality teams to ensure DFM/DFA compliance.
Support supplier selection and evaluate custom optical and precision mechanical components.
Participate in system-level design reviews and continuous improvement initiatives.