Exploring the supply chain risks behind advanced packaging and high-performance computing.
The global AI supply chain is entering another materials-driven constraint cycle. While GPUs and HBM dominate headlines, a lesser-known material is emerging as a structural bottleneck: T-glass.
For semiconductor procurement leaders, understanding the T-glass shortage is critical. This specialized glass fiber cloth now plays a direct role in AI server production, ABF substrates, SSD controllers, advanced packaging, and high-speed storage systems heading into 2026.
What Is T-Glass?
T-glass (Type-T glass) is a high-performance, low-dielectric fiberglass material used in multilayer printed circuit boards and semiconductor substrate laminates.
It differs from traditional E-glass by offering:
- Lower dielectric constant (low-Dk)
- Lower signal loss at high frequencies
- Higher thermal resistance
- Greater dimensional stability under heat
These properties are essential in high-speed applications such as:
- AI accelerators
- Advanced GPUs
- PCIe Gen5 and Gen6 SSD controllers
- High-bandwidth memory packaging
- High-layer-count server PCBs
As signal speeds increase and routing density rises, standard materials introduce electrical loss. T-glass enables cleaner signal transmission and stable performance at AI data center speeds.
Why the T-Glass Shortage Is Emerging
AI server architectures require:
- Larger substrate footprints
- More PCB layers
- Higher-frequency signal integrity
- Increased thermal tolerance
This has effectively doubled demand for high-performance glass cloth entering 2025–2026.
Supply, however, is highly concentrated. Nittobo dominates certified T-glass production globally.
It is important to clarify the value chain:
-
Nittobo produces the T-glass material
-
Ajinomoto manufactures the ABF (Ajinomoto Build-up Film) material used in advanced substrates
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Substrate manufacturers combine ABF materials with T-glass reinforcement to produce high-performance AI substrates
As hyperscalers and AI chipmakers such as NVIDIA, Microsoft, Google, and Amazon secure substrate allocations for AI infrastructure, upstream T-glass demand rises accordingly.
The dynamic is not that AI companies are directly buying T-glass. Rather:
AI demand increases ABF substrate production → ABF substrates require T-glass → T-glass supply tightens → less availability for other applications.
That constraint then cascades into BT substrates and other PCB markets.
This is a structural concentration risk, not a short-term imbalance.
Cascading Consequences Across the Hardware Ecosystem
SSD Controller Shortages
T-glass is critical in high-speed SSD controller substrates, particularly for PCIe Gen5 and Gen6 architectures.
As T-glass availability tightens:
- Controller manufacturers face substrate constraints
- OEMs pull inventory forward
- Lead times extend
Industry forecasts suggest controller inventory pressure building into mid-2026, with pricing increases possible as supply tightens.
This is not just a memory issue. It is a storage infrastructure constraint.
BT Substrate Squeeze
As AI-related ABF substrate production absorbs more T-glass supply, BT (Bismaleimide-Triazine) substrate manufacturers receive less material.
BT substrates are widely used in:
Reduced T-glass allocation for BT substrates creates double-digit supply compression risk in non-AI segments.
In other words: AI infrastructure demand indirectly crowds out legacy and mid-tier applications.
Storage Market Pressure
When SSD controllers become constrained:
- NAND consumption slows
- Storage device assembly bottlenecks emerge
- OEMs consider specification adjustments
PC and smartphone manufacturers may reduce storage configurations, such as reverting to lower capacity tiers, to offset rising controller and substrate costs without increasing retail pricing.
This represents broader storage market pressure, not purely a DRAM cycle issue.
Can Alternative Suppliers Close the Gap?
Taiwan-based manufacturers such as Taiwan Glass and Fulltech Fiber Glass are pursuing low-Dk glass cloth qualification.
However:
- Yield stability remains under evaluation
- Long-term reliability validation is ongoing
- Scaled production is limited
Substitution may provide incremental relief, but structural concentration in advanced T-glass remains.
What to Expect in 2026
As T-glass tightness persists, buyers should anticipate:
- Longer lead times on advanced substrates
- Extended lead times on SSD controllers
- Allocation prioritization toward AI infrastructure
- Higher input costs passed downstream
- Increased pricing volatility across storage components
Material-level bottlenecks typically surface as cost inflation and delayed deliveries before they appear as outright shortages.
Procurement strategies must adjust accordingly.
The Strategic Shift: Materials Now Dictate AI Scale
The next phase of AI will be constrained less by model innovation and more by hardware material availability.
Advanced substrates, ABF supply, HBM allocation, and high-performance materials like T-glass are becoming primary gating factors.
Organizations should prioritize:
- 12–18 month demand visibility
- Early allocation commitments
- Diversified substrate exposure
- Continuous monitoring of upstream materials markets
Upstream risk now defines downstream availability.
Stay Ahead of Semiconductor Supply Chain Shifts
Material bottlenecks like the T-glass shortage rarely dominate headlines until allocations tighten further.
Sign up for Fusion Worldwide’s Monthly Market Intelligence Report to receive forward-looking analysis on semiconductor supply chain trends, AI infrastructure demand signals, memory pricing shifts, substrate availability, and emerging allocation risks shaping 2026 planning.
Connect with Fusion Worldwide to better understand supply risks and secure the components needed to support long-term AI and infrastructure planning.
Frequently Asked Questions
What is T-glass and why is it important in semiconductor manufacturing?
T-glass is a low-dielectric fiberglass used in advanced PCBs and semiconductor substrates. It supports higher signal speeds, thermal stability, and routing density, making it critical for AI servers, GPUs, high-speed storage, and advanced packaging.
Why is there a T-glass shortage?
Demand is rising rapidly due to AI infrastructure and advanced substrate production. Supply is concentrated among a small number of qualified manufacturers, creating structural constraints and longer lead times across the semiconductor supply chain.
How does the T-glass shortage affect SSD controllers and storage?
T-glass is used in high-speed SSD controller substrates. Tight supply can extend controller lead times, increase pricing, and delay storage deployments, especially in PCIe Gen5 and Gen6 environments.
Which industries are most exposed to T-glass supply risk?
AI and hyperscale data centers are driving demand, but the impact extends to automotive, industrial, and consumer electronics. Reduced allocation for BT substrates can create supply pressure across multiple end markets.
Can alternative suppliers close the supply gap?
New suppliers are working to qualify low-Dk materials, but reliability, yield, and scale remain challenges. Substitution may help at the margin, but structural supply concentration is expected to continue.
How should procurement teams respond to T-glass constraints?
Focus on long-term forecasting, early allocation, diversified sourcing, and closer supplier engagement. Monitoring upstream materials is becoming essential to managing risk and avoiding delays.
