Analytical Equipment and Instrumentation
Direct-drive with several Elliptec Motors
In this analytical device, we had to move a gas vial reproducibly within +/-750nm of a target position in all three dimensions. Any deviation would have been detrimental to measurement accuracy. For this reason, four Elliptec Motors were used to move a slider containing the vial slowly and consistently. We developed a sequential control scheme where only one motor is activated at a time while the other three motors function as a support for the slider.
Highly dynamic positioning of a contacting pin
An extremely light slider was combined with a very small precision-bearing to achieve the required high precision and motor dynamics: specifically, a distance of 500µm had to be covered within less than 4ms and each target position had to be reached with 25µm accuracy.
Movement in vacuum
The The Elliptec Motor makes low-cost high-precision motion for vacuum applications possible. It proved reliable motion under hard vacuum conditions (~10-7 mBar) with temperatures of up to 95°C and even while depositing a thin film of material by physical vapor deposition (PVD).
The motor consists of a stainless steel spring (surface area 220 mm²), an aluminum resonator (surface area 335 mm²), and a piezo ceramic (surface area 70 mm²). The driven element can be made from various vacuum compatible materials like ceramics, stainless steel, glass, or plastics. Due to the materials used in the motor and its small total surface area with no cavities, the motor shows a very small desorption rate. In addition, it can be exposed to temperatures of up to 160 °C without reduced performance. Even much higher temperatures can be reliably withstood if the piezo ceramics are repolarised with a 54V DC voltage after a baking procedure. The standard PVC-coated cables can be replaced by cables suited for the specific environment, such as teflon coated cables.
The versatility of the motor allows the adaption for special purpose applications with direct drives or with gear trains or levers. Due to the low price of the Elliptec Motor, it is suited for applications where a large number of substrates have to be moved simultaneously. With the Elliptec Motor, no complex mechanical systems are required.
