Silicon Photonics
Experience the surface precision that brings high-performance AI optical interconnects to life
- Co-packaged optics
- WDM transceivers
- Photonic ICs
In photonics, surface quality is the product.
Sidewall roughness sets the propagation-loss floor.
AI is pushing data centers beyond the bandwidth limits of copper — and silicon photonics is part of the answer. The surface quality that makes photonic devices perform starts at the etch step. Even nanometer-scale roughness on a waveguide sidewall scatters light, accumulating as propagation loss across the length of the waveguide and directly determining whether a device meets its performance spec. Atomic-level etch control is not a nice-to-have here. It is the enabling step.
As AI infrastructure leans harder on optics, the etch surface stops being a process detail and becomes a competitive one. The teams that treat surface finishing as a first-class step — not an afterthought — set the performance ceiling everyone else designs against.
Where AAT Fits
Silicon photonics has moved into volume production, driven by AI data center demand for optical interconnects. Co-packaged optics, high-density WDM transceivers, and photonic integrated circuits all require waveguides with sidewall roughness at the sub-nanometer scale — a surface quality that conventional RIE cannot reliably deliver. Nanometer-scale line edge roughness is the primary yield and performance limiter in silicon photonics fabrication today.
AAT's isotropic ALE mode serves as a post-RIE finishing step on waveguide sidewalls, grating coupler structures, and other photonic features where surface quality directly determines optical performance. ALE smooths surfaces to a degree RIE cannot achieve, directly reducing propagation loss and improving device yield.
Demonstrated Performance
- Synergy Factor>80%
- Linearity (R²)>0.9947
- Cycle Time~2 seconds
- Modification saturation~2.0 Å at 1 second
- Removal saturation~2.1 Å at 1 second
Self-limiting saturation confirmed at ~1 second for both steps — providing the repeatability that photonic device yield requires.
Source: SPIE Advanced Lithography + Patterning 2026, Paper 13984-24
The AAT Advantage
Sub-nanometer surface control.
AAT's precision mode operates at ~2 Å/cycle with confirmed self-limiting behavior. At that scale, the tool is conditioning the surface cycle by cycle — to a quality level that no continuous etch process can match.
Fast enough for production.
At ~2 seconds per cycle, atomic-level surface finishing does not need to be a bottleneck in your photonics process flow.