Piezo
•
Nano
•
Positioning
Piezo Operation in Inert GasAtmospheres
® actuatorswith a maximum operating
voltage of 120 V can be used in
any vacuum condition. How-
ever, the operation of HVPZT
actuators with dielectric layerthicknesses of 0.2 – 1.0 mm andnominal voltages to 1000 V is
not recommended in the pres-
sure range of 100 – 50000 Pa
(~1 – 500 torr).II.Outgassing behavior variesfrom model to model depend-ing on design. Ultra-high-vacu-um options for minimum out-
gassing are available for many
standard low-voltage and high-
voltage piezo actuators. Best
suited are PICMA
Piezo Actuators Piezo Actuators
Ceramic-insulated PICMA Vacuum Operation of Piezo Actuators
® Nanopositioning &
Scanning Systems Nanopositioning &
Scanning Systems
actuators are also recommend-ed for use in inert gases, such
as helium. To reduce the dan-
ger of flashover with high-volt-age piezos, the maximum oper-ating voltage must be reduced.
Semi-bipolar operation is rec-
ommended, because the aver-
age operating voltage can be
kept very low. All PI piezo actuators can beoperated at pressures below
100 Pa (~1 torr). When piezo
actuators are used in a vacu-
um, two factors must be con-
sidered:I.Dielectric stabilityII.Outgassing
Active Optics / Steering Mirrors Active Optics / Steering Mirrors
Tutorial: Piezo-
electrics in Positioning Tutorial: Piezo-
electrics in Positioning Capacitive
Industrial position sensors Capacitive Position
Sensors Piezo Drivers & Nano-
positioning controllers Piezo Drivers & Nano-
positioning Controllers Hexapods /
Micropositioning Hexapods /
Micropositioning Photonics Alignment
Solutions Photonics Alignment
Solutions
Motion controllers Motion Controllers
ff ). All materials used in UHV-com-patible piezo nanopositioners,
including cables and connec-
tors, are optimized for minimaloutgassing rates (see Fig. 39b).Materials lists are available on
request.
® ceramics(see Fig. 39a), because they
have no polymers and can
withstand bakeout to 150 °C
(see also “Options” in the“Piezo Actuators” sections, p.1-44
Ceramic
Linear motors & Stages Ceramic Linear Motors & Stages Index Index
I. The dielectric breakdown volt- age of a sample in a specificgas is a function of the pres-sure p times the industrial electrode dis-tance ps -product of1000 mm Pa (~10 mm torr).
That is why PICMA s . Air displays a highinsulation capacity at atmos-
pheric pressure and at very low
pressures. The minimum
breakdown voltage of ~300 Vcan be found at a
Fig. 39 a. PICMA ® actuators are made with ceramic-only insulation and candispense with any polymer coating. Result No measurable outgasing, insen-sitive to atmospheric humidity and a wider operating temperature range. Fig. 39 b. P-733.UUD UHV-compatible Xy stage for scanning microscopyapplications. PICMA ® ceramics are used here too. All materials used areoptimized for minimal outgassing. Materials lists are available on request. 4-37