What is Indium Phosphide (InP)?
Indium Phosphide (InP) is a semiconductor material (like silicon), but specifically optimized for high-speed photonics — i.e., generating and detecting light at telecom wavelengths (1310nm / 1550nm).
Why InP matters
Silicon → great for electrons (compute)
InP → great for photons (light)
If you need to generate laser light or modulate it at very high speeds, silicon struggles — InP is the gold standard.
Purpose of InP for companies like AAOI
It enables the laser itself
For optical transceivers:
- You need a laser source
- That laser must:
- Be stable
- Operate at telecom wavelengths
- Modulate at very high speeds
InP is the material used to build these lasers (DFB, EML, etc.)
Without InP → no high-performance optical transceivers
It enables high-speed modulation (100G → 800G → 1.6T)
As speeds increase:
- Signal quality becomes harder
- Noise, dispersion, and heat increase
InP allows:
- Higher bandwidth per lane
- Better signal integrity at long distances
- Lower error rates
This is why 800G / 1.6T optics still heavily rely on InP-based devices
It enables integration (PICs – Photonic Integrated Circuits)
Instead of:
- Discrete laser + modulator + detector
You can build:
- Integrated photonic chips (PICs) on InP
That means:
- Smaller size
- Lower power
- Better thermal performance
This is critical for:
- Dense data center optics
- Co-packaged optics (future)
It is a key vertical integration lever for AAOI
For Applied Optoelectronics:
- AAOI grows InP wafers (epitaxy) internally (MBE/MOCVD)
- Fabricates:
- Laser diodes
- Optical components
This gives:
- Cost control (vs buying lasers from Coherent / Lumentum)
- Supply security
- Custom device design
This is one of AAOI’s key differentiators vs “assembly-only” players.
InP vs Silicon Photonics
| Feature | InP | Silicon Photonics |
|---|---|---|
| Laser generation | ✅ Native | ❌ Needs external laser |
| Modulation speed | High | High (but more complex) |
| Cost | Higher | Lower at scale |
| Integration | Moderate | Very high (CMOS compatible) |
Industry trend:
- InP still dominates lasers
- Silicon photonics is growing for integration
- Many systems = hybrid (InP laser + SiPh modulator)
InP substrate suppliers
- AXT Inc
- Sumitomo Electric
- JX Advanced Metals
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