Controlling outgassing and particulate contamination at 10⁻⁹ Torr requires:

Ultra-Clean Actuation Architecture

Bearing Systems:

Hybrid ceramic bearings (Si₃N₄ balls with 440C races) with ionic plasma deposition

Dry-film lubricants (MoS₂/Ti nanocomposite) surviving 300°C bakeouts

Sealing Technology:

Helicoflex® metal seals maintaining <1×10⁻⁹ mbar·l/s leakage rates

Magnetic fluid seals rated for 10,000 hours at 10⁻⁸ Torr

Vacuum-Optimized Materials

Material Type Standard Options Outgassing Rate (ASTM E595)

Housing 316L VIM-VAR steel <5×10⁻¹¹ Torr·L/(s·cm²)

Windings Polyimide-nano-ceramic TVOC<0.01% TML<0.1%

Sensors Al₂O₃ ceramic PCBs TML<0.05% CVCM<0.01%

Particulate Control Systems

Tribological Management:

Non-contact magnetic bearings for Z-axis levitation (0.5μm air gap)

Diamond-like carbon (DLC) coatings on gear teeth (friction coefficient 0.08)

Particle Trapping:

Integrated ionic wind particle precipitators

Cryogenic adsorption pumps in hollow shaft cavities

UHV Validation Methodology

RGA Analysis: Residual gas spectrometry verifying hydrocarbon levels <10⁻¹² Torr

Particle Counting: In-situ laser scattering detecting >0.1μm particles (ISO 14644-14)

Bakeout Simulation: 250°C thermal cycling with dynamic torque monitoring

Case Study: EUV Lithography Rotary Stage

Our VHR-800U platform achieved certified performance in ASML NXE systems:

Particulate emission: <3 particles/hour (>0.05μm)

Outgassing rate: 2.7×10⁻¹² Torr·L/(s·cm²) after 72h bakeout

Angular stability: ±0.00015° under 10⁻⁹ Torr during 5nm overlay scanning