Layout Scale-Up Engineer

Limelight Health; Paris (TX); On-site; USD 150,000 - 210,000; Full time

Job summary

Alice & Bob is building the first universal, fault-tolerant quantum computer based on Schrödinger cat qubits, targeting scalable chip layouts for thousands of qubits.

This role focuses on physical-design infrastructure, PDK development, and automated flow creation for superconducting hardware. You will implement tile-based layouts, generators, and mask data prep to enable large-scale fabrication.

Qualifications

• 5+ years in physical design, custom/analog layout, PDK development, or mask data prep in a semiconductor context (CMOS backend, RF/analog, MEMS, or photonics).
• Track record scaling a layout methodology—replacing hand-drawn layout with generators, PCells, or hierarchical flows.
• Hands-on parasitic extraction experience—commercial or field-solver-based—and deck/rule-file development.

Responsibilities

• Build and own the PDK — layer stack, technology file, cells, and their DRC/LVS decks.
• Design a tile-based, hierarchical layout methodology with reticle-compatible tiles.
• Write and maintain layout generators turning architecture spec + frequency plan into DRC-clean GDSII/OASIS.
• Own mask generation end-to-end from floorplan to tape-out.
• Drive automation targets: >50% automated layout at 400 qubits, >80% at 1,000, >90% at 10,000+.
• Keep DRC/LVS/PEX runtime and file size tractable at 10^6–10^8 elements.
• Evaluate and deploy the EDA toolchain (Cadence/Siemens/Synopsys) and integrate with EM-simulation.
• Serve as physical-implementation signoff at design review gates ahead of mask release.

Skills

PDK development

Layout automation

Python scripting

GDSII/OASIS

DRC/LVS

Parasitic extraction

Mask data prep

EDA toolchains

Hierarchical layout

Tape-out ownership

Tools

Calibre xRC/xACT

Quantus

StarRC

gdstk

gdsfactory

KLayout API

Cadence

Siemens

Synopsys

Job description

Alice & Bob is developing the first universal, fault-tolerant quantum computer to solve the world’s hardest problems.

The quantum computer we envision building is based on a new kind of superconducting qubit: the Schrödinger cat qubit. In comparison to other superconducting platforms, cat qubits have the astonishing ability to implement quantum error correction autonomously!

We're a diverse team of 250+ brilliant minds from over 35 countries united by a single goal: to revolutionise computing with a practical fault-tolerant quantum machine. Are you ready to take on unprecedented challenges and contribute to revolutionising technology? Join us, and let's shape the future of quantum computing together!

About the Mission

Alice & Bob's current 48-qubit generation was hand-drawn — the next generations won't be. As we scale toward 1,000-, 10,000-, and eventually million-qubit chips, manual layout stops being an option: it doesn't scale, and it caps how fast we can iterate. This role exists to build the infrastructure — PDK, generators, automated flows — that lets chip complexity grow 10–1,000× while design cycle time stays flat.

About the Role

You'll build the layout infrastructure that makes that scaling possible — PDK, layout compilers, parasitic extraction, hierarchical verification, and mask generation. This is a semiconductor physical-design role applied to superconducting hardware, not a quantum physics one.

Responsibilities

• Build and own the PDK — layer stack, technology file, parametric cells (junctions, CPW, resonators, couplers, pads, airbridges/crossovers) — and their DRC/LVS decks
• Design a tile-based, hierarchical layout methodology: standardized reticle-compatible tiles, programmatic instantiation, and stitching for wafer-scale and multi-chip designs
• Write and maintain layout generators (Python/GDS or vendor EDA scripting) that turn architecture spec + frequency plan into DRC-clean GDSII/OASIS with zero manual drawing
• Own mask generation end-to-end: floorplan → hierarchical layout → DRC/LVS/PEX signoff → wafer map, test structures, PCM placement → mask data prep and tape-out package
• Drive automation targets: >50% automated layout at 400 qubits, >80% at 1,000, >90% at 10,000+
• Keep DRC/LVS/PEX runtime and file size tractable at 10⁶–10⁸ elements via hierarchical, cell-level, and incremental verification
• Evaluate and deploy the EDA toolchain (Cadence/Siemens/Synopsys-class or open-source) and integrate it with EM-simulation handoff
• Serve as physical-implementation signoff at design review gates ahead of mask release

Requirements

• 5+ years in physical design, custom/analog layout, PDK development, or mask data prep in a semiconductor context (CMOS backend, RF/analog, MEMS, or photonics), including at least one production tape‑out owned end‑to‑end
• Track record scaling a layout methodology — replacing hand‑drawn layout with generators, PCells, or hierarchical flows on a design that grew substantially in element count
• Hands‑on parasitic extraction experience — commercial (Calibre xRC/xACT, Quantus, StarRC) and/or field‑solver‑based (FastCap/FastHenry, BEM/FEM) — including deck/rule‑file development and correlation against EM or measurement
• Strong layout‑automation scripting: Python (gdstk/gdsfactory/KLayout API) and/or vendor languages (SKILL, Tcl)
• Fluent in DRC/LVS deck authoring, GDSII/OASIS, reticle and stepper constraints (field size, stitching, alignment marks), and tape‑out data prep
• Comfortable turning a frequency plan or floorplan constraint set into geometry

Nice to Have

• Experience with superconducting or cryogenic device layout (Nb/Ta/TiN/Al thin films, Josephson junctions, CPW resonators, airbridges) and the loss/crosstalk‑driven layout rules that come with it

Recruitment Process

• Screening Call with Grace, Talent Acquisition Specialist (30 min)
• Hiring Manager Interview with Felix (45 min)
• Technical Interview/Presentation with the Team (120 min)
• Leadership Team Interview (30 min)