About us
Plessey has a long history of innovation. Founded in 1956, we have evolved from one of Europe’s earliest semiconductor pioneers into the world’s most advanced MicroLED specialist. Over the decades, Plessey has built a first class, fully integrated platform designing, manufacturing, and engineering next-generation display technologies entirely in-house. This end-to end capability, combined with our strong IP portfolio, uniquely positions us to lead the scaling of MicroLEDs from lab innovation to high-volume production.
Our future is even brighter. We believe MicroLEDs will define the next era of technology—powering ultra-efficient AR/VR displays, driving optical processors that make AI faster and more sustainable, and enabling devices yet to be imagined. With our unique expertise and talented team, we are positioned to lead this transformation.
It’s an exciting time to join us: Plessey has recently been acquired by Haylo Labs, accelerating our growth and opening new opportunities.
Our Values
* Innovation
* Collaboration
* Commitment
* Care
About the Role
As a Senior Mask Designer, you will be responsible for the design, verification, and optimisation of photomasks used in MicroLED device fabrication. You will work closely with integration engineers & process engineers to translate design intent into manufacturable mask sets that meet stringent requirements for yield, performance, and reliability. You will also have the opportunity to contribute to various activities within the process development team.
Location
Based at our manufacturing facility in Plymouth, UK.
Key Responsibilities
* Design and develop photomasks for MicroLED devices and supporting structures
* Collaborate with device and process engineers to define mask requirements and design rules
* Optimise mask layout for manufacturability, process control, and yield enhancement
* Perform DRC (Design Rule Check), LVS (Layout vs. Schematic), and ERC (Electrical Rule Check) verification
* Manage mask data preparation (MDP) and interface with external external mask makers, Compugraphics
* Collaborate with development team and photolithography team
* Support tape-out process and ensure timely delivery of high-quality mask sets
* Maintain and update mask databases, design libraries, and documentation
* Drive continuous improvement in mask design flow, automation, and efficiency
* Contribute to the development team with other activities within fabrication and integration
Experience & Attributes:
* Bachelor’s or Master’s degree in Electrical Engineering, Microelectronics, Materials Science, Physics, or related field
* 2–5 years of experience in mask design, semiconductor layout, or related domain
* Proficiency with mask/layout CAD tools (e.g., Cadence Virtuoso, Mentor Graphics Calibre, K-Layout)
* Strong knowledge of semiconductor device structures and lithography principles
* Familiarity with design verification methodologies (DRC, LVS, MDP)
* Detail-oriented with strong problem-solving and analytical skills
* Ability to work in a fast-paced, cross-functional team environment
Advantage
* Experience in display technology, MicroLED, or compound semiconductor devices (GaN, InGaN, etc.) or experience with optical technologies
* Experience with process development and/or integration
* Knowledge of CMOS, MEMS, or optoelectronic device fabrication processes
* Scripting/programming skills (Python, Perl, SKILL, or similar) for layout automation
* Previous collaboration with mask vendors/foundries and understanding of mask manufacturing processes
Benefits & Perks
* 28 days holiday plus bank/public holidays
* Generous pension contributions
* Life assurance (4x salary)
* Private medical insurance
* Dental plan
* Onsite gym
* Free meals provided daily