Senior Test Engineer
II-VI Järfälla AB · Järfälla · Tills vidare · Deadline 2026-11-07
II-VI Järfälla AB (Coherent Corp) is seeking a **Senior Test Engineer** to support its indium phosphide (InP) wafer fabrication facility in Järfälla. In this role, you will take ownership of **wafer probe and bar testing** for InP-based laser diode products, advancing test capabilities across production, product development, qualification, and reliability. Key responsibilities include improving test yield, throughput, and measurement repeatability; driving automation and data analysis; maintaining Statistical Process Control (SPC); and leading test equipment investments and capability studies. You will also conduct root-cause analyses on test failures, define test plans for new products, and collaborate closely with Engineering and R&D teams while mentoring technicians and engineers. Applicants must hold a **bachelor’s or master’s degree** in Physics, Electrical Engineering, Photonics, Semiconductor Engineering, or a related discipline, alongside several years of industrial experience in semiconductor test engineering. Essential requirements include practical experience in wafer probe and bar testing, solid knowledge of electrical, optical, and electro-optical characterisation, and hands-on competence with SPC, Design of Experiments (DOE), and Measurement System Analysis (MSA). Experience with data analysis or automation using Python, JMP, MATLAB, or similar tools is required, while familiarity with InP technology is highly desirable.
Coherent Corp is the global leader in photonics, designing and manufacturing advanced laser, optical, and materials technologies. Our innovations power semiconductor manufacturing, AI infrastructure, advanced communications, and precision industrial systems worldwide. With a global footprint and cutting-edge manufacturing and R&D, we’re shaping the future of high-tech industries.
In Sweden, our teams operate Sweden’s only full-scale indium phosphide wafer fabrication facility, where we design, manufacture, and test some of the world’s fastest optical chips under one roof, supporting AI infrastructure, data centres, and global communications networks worldwide.
Senior Test Engineer
As Senior Test Engineer, you will play a key role in advancing the test capabilities supporting our InP-based laser diode products. You will take ownership of wafer probe and bar testing, driving improvements in equipment, methodologies and automation to enhance product quality, yield and production efficiency.
This is an exciting opportunity to become a recognised technical expert within the production team, working closely with Engineering and R&D to support product qualification, new product introduction and the development of advanced testing solutions.
What you will be doing...
- Owning wafer probe and bar test processes within your designated area.
- Providing robust test capabilities for production, product development, qualification and reliability activities.
- Supporting wafer-level and bar-level testing of InP optoelectronic products.
- Supervising test operations and proactively identifying quality and yield issues.
- Improving test yield, throughput, measurement repeatability and data integrity.
- Developing new test methodologies, automation and data-analysis solutions.
- Establishing and maintaining Statistical Process Control (SPC) within production.
- Leading test process qualifications and measurement capability studies.
- Defining test plans and evaluation methods for new products, processes and equipment.
- Partnering with Process Integration, Device Engineering and R&D on product qualification.
- Leading test equipment investments, technical evaluations and supplier selection.
- Performing root-cause analysis of test failures and production yield losses.
- Creating technical reports, work instructions, specifications, qualification reports and project plans.
- Training and mentoring technicians and engineers on test equipment, software and procedures.
- Acting as the subject matter expert for wafer probe and bar testing of InP laser diodes.
About You
- Bachelor’s or master’s degree in Physics, Electrical Engineering, Photonics, Semiconductor Engineering or a related discipline.
- Several years of industrial experience in semiconductor test engineering.
- Experience with wafer probe and bar testing.
- Strong knowledge of electrical, optical and electro-optical characterisation.
- Experience working with optoelectronic components or laser diodes; knowledge of InP technology is highly desirable.
- Practical experience with SPC, Design of Experiments (DOE) and Measurement System Analysis (MSA).
- Data-analysis or automation experience using Python, JMP, MATLAB or similar tools.
- A proactive and systematic approach, with the ability to drive improvements in a production environment.
Ensure adherence to company’s values (ICARE) in all aspects of your position:
Integrity – Create an Environment of Trust
✨ Collaboration – Innovate Through the Sharing of Ideas
Accountability – Own the Process and the Outcome
Respect – Recognize the Value in Everyone
Enthusiasm – Find a Sense of Purpose in Work
Application & Selection:
Candidates who wish to apply should submit a cover letter detailing their interest in the position and how their skills and experience align with the requirements of the role.
If you require any adjustments or accommodations during the application process, please reach out to Molly.Almgren@coherent.com. We are committed to creating an inclusive and accessible recruitment experience and encourage applications from individuals of all backgrounds.