We develop audacious AI computing platforms that elevate performance, energy and economic efficiencies, enabling our customers to rapidly deploy innovations in their AI applications.
We develop audacious AI computing platforms that elevate performance, energy and economic efficiencies, enabling our customers to rapidly deploy innovations in their AI applications.
Core product: Photonic Fabric — optical interconnect platform for chip-to-chip and memory disaggregation
Founded: 2020
Founders / key leaders: David (Dave) Lazovsky (Co‑Founder, CEO); Preet Virk (Co‑Founder, COO); Phil Winterbottom (CTO, technical co‑founder)
Recent funding: $250M Series C1 (Mar 11, 2025); $175M Series C (Mar 27, 2024); $100M Series B (Jun 28, 2023)
Headcount (approx.): 142
AI infrastructure, data-center interconnects, memory disaggregation
2020
Semiconductors / AI infrastructure
$100M
Series B announced June 28, 2023
$175M
Series C announced March 27, 2024
$250M
Series C1 announced March 11, 2025
“Mix of strategic and institutional investors including U.S. Innovative Technology Fund, Fidelity, AMD Ventures, Koch Disruptive Technologies, Temasek, BlackRock, Tiger Global”
About Celestial AI As Generative AI continues to advance, the performance drivers for data center infrastructure are shifting from systems-on-chip (SOCs) to systems of chips. In the era of Accelerated Computing, data center bottlenecks are no longer limited to compute performance, but rather the system’s interconnect bandwidth, memory bandwidth, and memory capacity. Celestial AI’s Photonic Fabric™ is the next-generation interconnect technology that delivers a tenfold increase in performance and energy efficiency compared to competing solutions.
The Photonic Fabric™ is available to our customers in multiple technology offerings, including optical interface chiplets, optical interposers, and Optical Multi-chip Interconnect Bridges (OMIB). This allows customers to easily incorporate high bandwidth, low power, and low latency optical interfaces into their AI accelerators and GPUs. The technology is fully compatible with both protocol and physical layers, including standard 2.5D packaging processes. This seamless integration enables XPUs to utilize optical interconnects for both compute-to-compute and compute-to-memory fabrics, achieving bandwidths in the tens of terabits per second with nanosecond latencies.
This innovation empowers hyperscalers to enhance the efficiency and cost-effectiveness of AI processing by optimizing the XPUs required for training and inference, while significantly reducing the TCO2 impact. To bolster customer collaborations, Celestial AI is developing a Photonic Fabric ecosystem consisting of tier-1 partnerships that include custom silicon/ASIC design, system integrators, HBM memory, assembly, and packaging suppliers.
About The Role We are seeking an experienced Silicon Packaging Layout Engineer with expertise in heterogeneous integration. The ideal candidate will have a strong background in semiconductor packaging design to drive Celestial AI’s Photonic Fabric Package solutions. This role requires cross-functional design collaboration with multiple engineering groups, such as Packaging, ASIC, AMS, Photonics, and external partners to ensure design for manufacturing, assembly, reliability, and cost.
Essential Duties And Responsibilities
2.5D and 3D Design Planning and Execution:
Support Silicon interposer and RDL based design planning and execution for advanced packaging architectures.
Support bumpmap and test collateral release for test vehicle and product designs.
Netlist management for heterogeneous chiplet assemblies using latest EDA solutions.
Layout Expertise:
Support all aspects of silicon layout based on I/O, SI-PI and form factor requirements, including routing, design for reliability, thermal, mechanical, manufacturability, bumping, substrate, material selection, assembly, and support for testing.
Support cross-functional silicon layout needs.
Fab and OSAT Engagement:
Support activities related to silicon manufacturing such as fab design reviews and tape-out aligned with OSAT requirements.
Actively support test vehicle definition and design for assembly test vehicles.
Qualifications
Education: BS in EE/ECE/MSE/ME/ChemE or related disciplines.
Experience: 4 years of experience in silicon interposer and RDL designs for heterogeneous architectures.
Technical Expertise:
Experience working with design tools such as Cadence Virtuoso and Klayout.
Familiarity with AutoCAD tools and file formats.
Layout experience for various 2.5D/3D packaging technologies including InFO, CoWoS, FoCoS and EMIB.
Familiarity with cross-functional packaging areas: Si floor plan, package, assembly design rules, BOM, enabling material/process technologies, thermal, mechanical, Signal/Power Integrity, design for manufacturing, assembly, reliability, and cost.
Familiarity with photonics packaging is a plus but not necessary.
Foundry and OSAT Engagement:
Experience working with wafer foundries to meet design for manufacturing, yield, and reliability.
Experience working with OSATs to meet assembly requirements.
Industry Knowledge: Familiarity with latest advanced packaging architectures.
Soft Skills: Strong analytical, problem-solving, cross-functional collaboration, project management, and technical presentation skills.
Preferred Qualifications
LOCATION : Santa Clara, CA
For California Location:
As an early stage start up, we offer an extremely attractive total compensation package inclusive of competitive base salary, bonus and a generous grant of our valuable early-stage equity. The target base salary for this role is approximately $165,000.00 - $205,000.00. The base salary offered may be slightly higher or lower than the target base salary, based on the final scope as determined by the depth of the experience and skills demonstrated by candidate in the interviews.
We offer great benefits (health, vision, dental and life insurance), collaborative and continuous learning work environment, where you will get a chance to work with smart and dedicated people engaged in developing the next generation architecture for high performance computing.
Celestial AI Inc. is proud to be an equal opportunity workplace and is an affirmative action employer.