GlobalFoundries (GFS): Silicon Photonics Research

Through March 2026. All claims sourced with dates and URLs.

Through March 2026. All claims sourced with dates and URLs.


1. AMF (Advanced Micro Foundry) Acquisition & Integration

Acquisition announced November 17, 2025. NOT 2023 — that was likely earlier speculation or a different event. The actual deal closed in late 2025.

Key Facts

Integration Milestones

Sources: - GF Press Release — AMF Acquisition (Nov 17, 2025) - GF Blog — AMF and InfiniLink - Gazettabyte — GF SiPho Push After AMF - TrendForce — Largest Pure-Play SiPho Foundry - Semiconductor Today — AMF Acquisition


2. GF Fotonix Platform Updates

Platform Architecture

GF Fotonix is GF’s monolithic 300mm silicon photonics platform — the first in the industry to combine differentiated photonics features with 300GHz-class RF-CMOS on a single silicon wafer. Launched in 2022 at 100G per wavelength.

Next-Generation Fotonix (Showcased at OFC 2025, April 1-3, San Francisco)

Bandwidth upgrade: - 200G/lambda — doubled from the original 100G/lambda capability - Supports PAM4 signaling - Roadmap targets 400G/lambda solutions

Active component improvements: - Upgraded modulators: micro-ring, Mach-Zehnder, and Ring Assisted Mach-Zehnder variants - Upgraded photodiodes and transistors for monolithic integration - Enhanced modulator bank yield for multi-lambda “slow and wide” architectures

Passive component improvements: - V-groove pitch reduced from 250um to 127um — 2x higher optical beachfront density - Silicon nitride (SiN) spot-size converters — >4x improvement in power handling capacity

PDK capabilities: - Integrated photonics + RF CMOS or photonics-only flow options - Free-form passive component design support - Native custom device design via industry-leading device simulator files - Both CWDM and DWDM multiplexing component libraries - PDK 1.0 originally available April 2022; continuously updated since

Advanced integration features: - Through-silicon vias (TSVs) enabling 2.5D/3D stacking of electrical ICs atop photonic ICs - Supports 3nm electronic ICs with high-density pitch - Wafer-level and die-level detachable fiber attach solutions (demonstrated at OFC 2025)

Manufacturing tracks: 1. Monolithic integration — CMOS + RF + photonics on single chip 2. Photonics-only flow — fewer mask steps, lower cycle time, supports advanced packaging stacks (customers can source electronic ICs from other foundries)

Design Ecosystem Partners

Sources: - GF Blog — Next-Gen Fotonix (OFC 2025) - GF Silicon Photonics Platform Page - Enosemi + GF Fotonix IP Announcement (Sept 2024) - StarIC + GF Partnership - Corning + GF Collaboration (Sept 2025)


3. Fab Capacity & CHIPS Act Funding

Clarification: GF9 vs. Fab 8 vs. Essex Junction

Advanced Packaging and Photonics Center (Malta, NY)

Announced January 17, 2025. First-of-its-kind facility in the U.S.

$16 Billion U.S. Investment Plan (June 4, 2025)

CHIPS Act Funding (for all GF U.S. operations)

Vermont Fab (Essex Junction) — SiPho Relevance

Sources: - GF Press Release — Advanced Packaging and Photonics Center (Jan 17, 2025) - GF Press Release — $16B U.S. Investment (June 4, 2025) - Governor Hochul Announcement — Photonics Center - NIST CHIPS — GlobalFoundries Vermont - GF CHIPS Act Funding Announcement - Semiconductor Today — $3B R&D for SiPho/Packaging/GaN


4. Customer & Design Wins

Tier-1 Platform Partners (announced at GF Fotonix launch, March 2022; relationships ongoing)

Customer Focus Area
Broadcom Optical solutions for networking switches, CPO research
Cisco Custom SiPho for DCN/DCI applications (notable — Cisco also uses TSMC)
Marvell TIAs and modulator drivers for optical transceivers
NVIDIA High-bandwidth, low-power optical interconnects for data centers
MACOM Telecoms, defense, data center applications
Ayar Labs Monolithic electronic/photonic chip-to-chip optical I/O
Lightmatter Photonic compute technology
Ranovus SiPho IP cores and chiplets

Quantum Computing Customers

Customer Focus Area
PsiQuantum Manufacturing quantum chips on SOI substrates (Chicago fab)
Xanadu Quantum computing hardware

Design Ecosystem Partners

Partner Contribution
Ansys Simulation tools
Cadence EDA tools
Synopsys EDA tools (GF also acquired Synopsys’ processor IP business)
Enosemi Silicon-validated 100G PAM4 IP blocks
StarIC High-speed TIA and driver library for 45SPCLO
Corning Detachable fiber connectors for CPO
Flexcompute Photonic device design tools linked to manufacturing stack

Post-AMF Customer Expansion

What I Could NOT Confirm

Sources: - GF Press Release — Fotonix Launch with Industry Partners (March 2022) - Gazettabyte — Customer Momentum Post-AMF - Quantum Insider — PsiQuantum/Xanadu


5. Revenue Contribution

Silicon Photonics Revenue

Period SiPho Revenue Growth Source
FY2024 ~$100M (implied) Implied from “doubled in 2025”
FY2025 >$200M ~2x YoY Q4 2025 earnings call
FY2026E ~$400M (implied) “nearly double again” Q4 2025 guidance
FY2028E target $1B run-rate Accelerated from prior target CEO Tim Breen, Q4 2025 call
AMF 2026 contribution >$75M Incremental to above AMF acquisition press release

As Percentage of Total Revenue

Segment Context

Wafer Volume

Sources: - Motley Fool — GFS Q4 2025 Earnings Transcript (Feb 11, 2026) - GFS Q4 2025 Financial Results - TelecomLead — SiPho Revenue Doubles


6. Competitive Positioning (as of Early 2026)

The Four-Way Race

Foundry Approach Status Key Differentiator
GlobalFoundries Monolithic SiPho (Fotonix) + acquisitions (AMF, InfiniLink) Production. >$200M revenue in 2025 Largest pure-play SiPho foundry. End-to-end from design to packaged module. Dual-track (monolithic or photonics-only)
TSMC COUPE packaging technology + CoWoS integration Qualifying pluggables 2025, CPO mass production targeted 2026 Massive scale advantage. Integrating SiPho into existing CoWoS advanced packaging. Most patent filings (50 in 2024)
Tower Semiconductor Organic capacity expansion (200mm US/Israel + 300mm Japan) $52M SiPho revenue in Q3 2025 (~70% YoY growth) Tripling capacity by mid-2026, 5x by Dec 2026. $920M total SiPho investment. Plans to challenge GF for #1
Intel Pioneer but declining patent output, still in R&D/demo stage for CPO Patent filings falling (26 in 2024, down from 46 in 2023) Has deep IP history but restructuring has slowed execution. Not competitive on production timeline

GF’s Competitive Advantages

  1. Only monolithic platform combining photonics + 300GHz RF-CMOS on 300mm — competitors either use separate chips or are behind on integration
  2. Broadest customer base after AMF acquisition (300+ customers from AMF alone, plus Fotonix customers)
  3. Global manufacturing footprint — U.S. (Malta, NY), Singapore, Dresden — supply chain diversification matters to customers
  4. End-to-end capability post-InfiniLink — from design IP through to packaged optical engine modules
  5. First U.S. photonics packaging center — onshore manufacturing, processing, packaging, and testing for defense/aerospace

GF’s Competitive Risks

  1. TSMC’s entry is the big threat. TSMC brings massive scale, CoWoS integration, and relationships with the same customers (Broadcom, Nvidia, etc.). COUPE mass production in 2026 could shift the market
  2. Tower is growing faster organically — 5x capacity increase by end of 2026 is aggressive
  3. GF doesn’t manufacture the most advanced logic nodes — customers needing 3nm EICs must still go to TSMC/Samsung, then co-package with GF’s photonic ICs
  4. Intel, while weakened, has deep IP and could re-enter aggressively if its foundry business stabilizes

Industry Context

Sources: - TrendForce — Intel Loses SiPho Lead to TSMC - TrendForce — TSMC COUPE at SEMICON Taiwan - Tower Semiconductor — CPO Foundry Technology (Nov 2025) - LightCounting — 2026 Year of Silicon Photonics - Calcalist — Tower Record Quarter, SiPho Growth - 36kr — Silicon Photonics Foundry War


Timeline of Key Events

Date Event
Mar 2022 GF Fotonix launched with 10+ industry partners, PDK 1.0 available
Sep 2024 Enosemi releases silicon-validated IP for Fotonix
2024 StarIC partnership and IP library for 45SPCLO process
Jan 17, 2025 Advanced Packaging and Photonics Center announced (Malta, NY)
Apr 1-3, 2025 Next-gen Fotonix showcased at OFC 2025 (200G/lambda, TSVs, fiber attach)
Jun 4, 2025 $16B U.S. investment plan announced
Sep 2025 Corning detachable fiber connector partnership announced; ECOC 2025 demo
Nov 17, 2025 AMF acquisition announced
Nov 2025 InfiniLink acquisition announced
Feb 11, 2026 Q4 2025 earnings: SiPho >$200M revenue, “nearly double again” in 2026
Mar 2026 GF positions SiPho as “must-have connectivity layer” for AI data centers