Lightmatter is leading the revolution in AI data center infrastructure, enabling the next giant leaps in human progress. The company invented the world’s first 3D-stacked photonics engine, Passage™, capable of connecting thousands to millions of processors at the speed of light in extreme-scale data centers for the most advanced AI and HPC workloads.

Lightmatter raised $400 million in its Series D round, reaching a valuation of $4.4 billion. We will continue to accelerate the development of data center photonics and grow every department at Lightmatter!

If you're passionate about tackling complex challenges, making an impact, and being an expert in your craft, join our team of brilliant scientists, engineers, and accomplished industry leaders.

Lightmatter is (re)inventing the future of computing with light!

We are seeking a Thermal Engineer with strong expertise in thermal analysis and deep knowledge of semiconductor packaging technologies to join our team. In this role, you will work on leading-edge packaging technologies to enable AI architectures that set new industry standards in compute power, performance, and efficiency. As part of the Package Technology team, you will lead thermal analysis efforts required for product definitions, drive innovative thermal solutions, and conduct analysis and validation to deliver package and system designs that meet product requirements. Your work will contribute to advanced package and system designs that address power dissipation, assembly, and reliability challenges while delivering system-level solutions for leading-edge products in data centers and high-end compute segments

Responsibilities: 

  • Perform thermal simulations to influence package and system design.
  • Propose novel thermal solutions to enable the Lightmatter product portfolio by investigating relevant technologies and design concepts.
  • Develop and validate thermal models for various packaging designs, including modeling heat transfer, airflow, and thermal interactions within complex electronic assemblies.
  • Collaborate with design engineers to optimize thermal management solutions, including heat sinks, thermal interfaces, and cooling systems. Use CFD results to guide design iterations and improve thermal performance.
  • Drive characterization and validation of thermal designs and electronic assemblies through lab-scale prototyping and/or by initiating appropriate experiments with vendors.
  • Summarize and communicate findings to key stakeholders across Lightmatter, suppliers, and customers as required.
  • Develop analytical or semi-empirical models for quick-turn assessments of new product concepts.
  • Develop and maintain CFD tools, templates, and best practices to streamline the simulation process and improve efficiency.
  • Develop automation scripts using Python or MATLAB to enhance modeling efficiency.
  • Write comprehensive reports and document methodologies.

Required Qualifications:

  • M.S. or Ph.D. in Mechanical Engineering, Materials Science, Chemical Engineering, or a related engineering field.
  • 3-4 years of experience in package or system thermal analysis.
  • Deep knowledge of thermal conduction and convective heat transfer concepts.
  • Experience designing, modeling, testing, sourcing, and deploying advanced thermal management technologies such as TECs, heat pipes, vapor chambers, thermal interface materials, phase change materials, and liquid or air cooling systems.
  • Proficiency in performing steady-state and transient thermal analysis using ANSYS Icepak, ANSYS Fluent, and/or Flotherm.
  • Experience setting up and interpreting CFD simulations for complex geometries and boundary conditions.
  • Working knowledge of lab-scale validation techniques

Preferred Qualifications:

  • Knowledge of fluid dynamics and assembly process modeling for 2D/3D packaging technologies, with exposure to their thermal challenges.
  • Experience in two-phase immersion cooling and single- and two-phase liquid flow systems.
  • Knowledge of thermal technologies in high-performance computing and data centers.
  • Experience developing thermal control algorithms to optimize device and system performance.
  • Proficiency in statistical analysis tools and techniques such as DOE and JMP.
  • Excellent communication skills and the ability to work effectively in cross-functional teams

We offer competitive compensation. The base salary range for this role determined based on location, experience, educational background, and market data.

Salary Range
$139,000—$210,000 USD

Benefits

  • Comprehensive Health Care Plan (Medical, Dental & Vision)
  • Retirement Savings Matching Program
  • Life Insurance (Basic, Voluntary & AD&D)
  • Generous Time Off (Vacation, Sick & Public Holidays)
  • Paid Family Leave
  • Short Term & Long Term Disability
  • Training & Development
  • Commuter Benefits
  • Flexible, hybrid workplace model
  • Stock Option Plan

Lightmatter recruits, employs, trains, compensates, and promotes regardless of race, religion, color, national origin, sex, disability, age, veteran status, and other protected status as required by applicable law.

 

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