# Memory

High Bandwidth Memory (HBM) is essential for AI training. SK Hynix and Samsung control over 95% of global HBM production, with chronic supply shortages.

**Measure:** High Bandwidth Memory (HBM) Production Share

**US & Allies Score:** 9.0/10  
**China Score:** 3.0/10  
**Leader:** US & Allies

## Key Metrics

- **HBM share:** HBM Share (%) = (Supplier HBM output / Global HBM output) × 100
- **Stack yield:** Stack Yield ≈ Π(Die yield per layer) × TSV/bump yield × packaging yield

## What matters in this layer

HBM capacity, binning, and reliability determine effective accelerator throughput. When HBM is short, compute is short. The constraint is as much packaging and qualification as it is DRAM wafer capacity.

### Supplier concentration

A small set of firms controls most HBM output. This amplifies shocks, makes long‑term contracts valuable, and turns ramp decisions into strategic levers.

### Packaging coupling

HBM availability depends on advanced packaging throughput and substrates. Memory cannot be analyzed in isolation from the packaging layer.

## Recent Developments

### SK Hynix Dominates HBM Market for AI
*2 days ago | Memory*

SK Hynix controls over 50% of the HBM market, with supply agreements locked in with NVIDIA and AMD through 2026.

### Samsung Ramps HBM3E Production
*1 week ago | Manufacturing*

Samsung has qualified its HBM3E memory with major GPU manufacturers and is rapidly scaling production.

### Micron Breaks Ground on New York Memory Fab
*2 weeks ago | Investment*

Micron has begun construction on a $100 billion memory fab complex in New York, strengthening US domestic production.