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Principal Design Engineer

Coherent

Listing collected from Coherent's career site. NextChapter is independent of Coherent.

Fremont, CA · Posted July 23, 2026

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About the job

Primary Duties & Responsibilities

Lead the design, simulation, development, and optimization of high-speed, high-sensitivity InGaAs/InP photodiodes for advanced optoelectronic applications.

Define device architecture and performance targets to meet demanding customer and market requirements.

Partner with epitaxial growth and semiconductor process engineers to develop and optimize device structures and fabrication processes.

Analyze device performance through simulation, characterization, and failure analysis to continuously improve speed, sensitivity, reliability, and manufacturability.

Collaborate with test and reliability engineers to develop characterization plans, validate device performance, and ensure long-term product reliability.

Work closely with internal wafer fabrication teams and external manufacturing partners to develop and scale advanced manufacturing technologies.

Lead technical problem-solving efforts throughout the product development lifecycle, from concept through production release.

Drive innovation by identifying and implementing new photodiode structures, materials, and fabrication techniques.

Mentor junior engineers and provide technical leadership across cross-functional development teams.

Stay current with emerging technologies, industry trends, and scientific advancements in photonic device design. You will lead the design and product development of high-speed and high-sensitive InGaAs /InP photodiodes

Education & Experience

PhD with 10+ years of relevant experience

Optoelectronic device design and simulation

Photodiode epi materials growth, development and quality control

Photodiode wafer front process and backend process.

Photodiode test and characterization.

Photodiode reliability qualification.

Skills

Lead the architectural designs of high-speed and high-sensitive InGaAs / InP photodiodes

Design high-speed and high-sensitive photodiode epi structures

Design both front- and back-end wafer process flows

Support and Perform device characterization

Support product qualification and release

Working Conditions

This role will be based on-site in Fremont, CA.

Regular use of a computer and other office equipment is necessary.

Physical Requirements

Sitting for extended periods while working on a computer or in meetings.

Use of hands and fingers for typing, writing, and handling documents.

Occasional lifting of objects or materials up to 20 pounds for administrative tasks.

Ability to communicate verbally and in writing.

Safety Requirements

All employees are required to follow the site EHS procedures and Coherent Corp. Corporate EHS standards.

Quality and Environmental Responsibilities

Depending on location, this position may be responsible for the execution and maintenance of the ISO 9000, 9001, 14001 and/or other applicable standards that may apply to the relevant roles and responsibilities within the Quality Management System and Environmental Management System.

Culture Commitment

Ensure adherence to company’s values (ICARE) in all aspects of your position at Coherent Corp.:

I ntegrity – Create an Environment of Trust

C ollaboration – Innovate Through the Sharing of Ideas

A ccountability – Own the Process and the Outcome

R espect – Recognize the Value in Everyone

E nthusiasm – Find a Sense of Purpose in Work

Coherent Corp. is an equal opportunity/affirmative action employer. All qualified applicants will receive consideration for employment without regard to sex, gender identity, sexual orientation, race, color, religion, national origin, disability, protected Veteran status, age, or any other characteristic protected by law.

If you need assistance or an accommodation due to a disability, you may contact us at talentacquisition@coherent.com .

Coherent is a global leader in lasers, engineered materials and networking components. We are a vertically integrated manufacturing company that develops innovative products for diversified applications in the industrial, optical communications, military, life sciences, semiconductor equipment, and consumer markets. Coherent provides a comprehensive career development platform within an environment that challenges employees to perform at their best, while rewarding excellence and hard-work through a competitive compensation program. It's an exciting opportunity to work for a company that offers stability, longevity and growth. Come Join Us!

Note to recruiters and employment agencies: We will not pay for unsolicited resumes from recruiters and employment agencies unless we have a signed agreement and have required assistance, in writing, for a specific opening.