Piezoelectric Motors & Piezoelectric Actuators for Semiconductor Manufacturing
Engineered for vacuum, non-magnetic environments and nanometer-class motion control.
Why PiezoLEGS® in the fab
- Vacuum & bake-out ready. Dedicated PiezoLEGS® variants are prepared for vacuum with minimized outgassing and bake-out up to 125 °C, ideal for vacuum chambers and load-locks.
- Non-magnetic by design. Piezoceramic elements and non-magnetic alloys keep magnetic flux below sensor noise (~<1 nT at 10 mm), safe around e-beam columns and high-field tools.
- True direct drive. No gears or screws results in zero backlash, smooth motion, compact footprint, and fewer particles from moving transmissions.
- Sub-nanometer resolution & fast settle. Micro-stepping of the drive waveform enables nanometer to sub-nanometer positioning with excellent dynamic control.
- Power-off holding. The friction-walk mechanism is inherently self-locking and hold position with zero power draw, a major thermal and energy advantage in vacuum.
- Force in a small package. Standard PiezoLEGS® linear actuators cover 6.5–40 N (with strokes to ~75 mm): platform extensions reach 300–450 N for heavy optics and wafer-level subsystems.
Where they excel in semiconductor equipment
- Optics & metrology: focus/zoom, filter/aperture selection, interferometer alignment, mask/reticle fine-positioning. Piezo motors are widely used for UHV/non-magnetic positioning in semiconductor metrology.
- Probe & test: sub-micron approach, contact force tuning, drift-free hold during long measurements.
- Wafer handling modules: end-effector Z-trim, chuck leveling, alignment pins, miniature shutters.
- E-beam / ion tools: non-magnetic actuators for stage accessories and calibration mechanisms.
Performance at a glance (typical)
- Resolution:
- Open loop: < 1 nm with controller micro-stepping (up to 8192 micro-steps per waveform step)
- Closed loop: 12.5 nm
- Speed: from nanometers/s to ~15–24 mm/s depending on model/driver.
- Stroke: defined by drive-rod length; standard options up to ~74.5 mm on compact models.
- Force: 6.5 N, 20 N, 40 N standard; 300–450 N in covered/heavy-duty variants.
- Vacuum rating: to ~10⁻⁷ torr usually with non-magnetic build; prepared for 125 °C bake-out.
Example: LL10D non-magnetic/vacuum compatible motor with 6.5 N stall, 7 N hold, 0–15 mm/s, up to 74.5 mm stroke; magnetic flux < 1 nT at 10 mm.
Integration & control
- Controllers: PMD301 (module) and PMD401 (board-level) over RS-485/USB, supporting micro-stepping to sub-nm resolution and multi-axis chaining.
- Feedback: works with external encoders for closed-loop motion; direct-drive architecture simplifies control loops (no screw/gear compliance).
- Form factors: compact actuators with swappable drive-rod lengths, vacuum and non-magnetic builds for fab integration
Piezoelectric motor vs. stepper/BLDC in vacuum
| Criterion | Piezoelectric motor / actuator (PiezoLEGS®) | Stepper/BLDC with screw |
| Magnetics | Non-magnetic; no stray fields | Requires magnetic mitigation; can disturb e-beam/ion paths |
| Backlash | None (direct friction-walk) | Depends on screw/gear and preload |
| Holding | Self-locking at rest; zero power | Hold torque → heat in vacuum |
| Heat load | Very low at hold; efficient small moves | Higher, especially under hold/constant current |
| Vacuum readiness | Vacuum-prepared variants; bake-out to 125 °C | Special greases, outgassing control needed |
| Resolution | Sub-nm with micro-stepping & 12.5 nm with encoder | Limited by screw pitch, compliance, encoder |
Specifying a PiezoLEGS® actuator for your tool
- Environment: target pressure (HV/UHV), bake-out profile, magnetic constraints, cleanliness
- Axis mechanics: required stroke, external guiding (required), and stiffness budget.
- Throughput: speed and settle time; specify move profile (step-settle vs. scan).
- Load case: continuous vs. peak force, and duty cycle.
- Feedback & control: encoder type and resolution, interface (RS-485/USB), and controller form factor.
Frequently asked questions
Are PiezoLEGS® motors piezoelectric motors or piezoelectric actuators?
Both. The motor is a piezoelectric actuator assembly that performs useful mechanical work as a piezoelectric motor via a controlled walking sequence.
Do they work in UHV and strong magnetic fields?
Non-magnetic/vacuum versions are specified to vacuum levels around 10⁻⁷ torr with non-magnetic construction. Piezo mechanisms are widely used in UHV and strong-field environments across semiconductor metrology and positioning. For UHV beyond that, consult us for materials/finish options.
How much force and travel can I get?
Standard linear PiezoLEGS® motors cover 6.5–40 N with strokes up to ~75 mm. Covered/heavy-duty variants extend to 300–450 N. Travel is set by the drive-rod length.
What’s the real-world resolution?
With an encoder and PMD-series controller, sub-nanometer command increments are achievable; application-level resolution depends on mechanics and noise.
Work with Acuvi’s engineering team
Whether you’re upgrading a metrology axis, adding a non-magnetic focus stage, or redesigning a vacuum mechanism, our engineers can help you size the motor, controller, and feedback to your semiconductor requirements—and deliver an OEM-ready assembly.
Talk to an engineer (We’ll map requirements, share reference designs, and provide samples/EVKs.)