Kurt J. Lesker Company

Intro to Rotary Telescopic Transfer Arm

Radial systems require the precise transfer of samples between multiple chambers for preparation and analysis. This is handled from the central radial distribution chamber.

The Radial Telescopic Transfer Arm (RTTA) represents a step-change advance in radial distribution technology offering unrivalled performance over conventional designs at a comparable cost. The RTTA uses a high torque magnetically coupled MagiDrive (see catalogue Section 1) to provide extremely stiff coupling for radial motion. This radial motion is used to align the transfer arm with the desired chamber port achieving angular reproducibility of <0.2mm. A second MagiDrive is used to drive the innovative telescopic mechanism which provides an arm extension of 760mm (2.5x that of conventional designs) to transport the sample in and out of the desired satellite chamber. The precision slide mechanism achieves linear reproducibility of <0.2mm with <1mm deflection at full extension with a 10N load.

RTTA Key Advantages

2.5x the reach of conventional systems
Typically <1mm deflection at full extension with 10N load
Excellent substrate position reproducibility: <0.2mm laterally & axially
2 and 3-Axis variants
True UHV performance

The RTTA is available in 2-axis and 3-axis versions. The 2-axis RTTA provides rotation for port alignment and arm extension for sample transfer. The 3-axis RTTA also includes the ability to lift and lower the sample arm for gravity based hand off typically used on MBE, sputtering and CVD sample manipulators and heating stages.

The RTTA enables you to:

1. Reach further

2. Use a smaller chamber for the same stroke

3. Gain access to valuable chamber 'real estate'

User-Friendly Manual Arm Alignment

The manual version of the RTTA is supplied with an innovative, user-friendly system to align the arm with the desired ports.

Fitted to the top of the thimble ring are a number of adjustable position stops. These engage with a pair of spring-loaded bearings that can be withdrawn while the drive is rotated into position then re-engaged to hold the drive firmly in position by using a simple lever. Each stop can be individually aligned with a port axis to define default angular positions which are very reproducible.

True UHV Rotation With No Oil, Slip Rings, Bellows or Differential Pumping

The Radial Telescopic Transfer Arm is actuated by the MD64LB and MD40 magnetically-coupled MagiDrive rotary feedthroughs. They provide true UHV performance, without any bellows, oil, slip rings or differential pumping. The larger MD64LB has a break-away torque of ~40Nm, providing an extremely stiff coupling, ideal for rotating the arm assembly. The smaller MD40 actuates the mechanisms to drive the arm in and out.

Motorized 'Talk Free' Concept

An issue with many radial distribution chambers system designs is the issue of the rotating arm motion causing the arm extension assembly to move (often described as the axis cross-talk). Therefore, rotation of the arm also causes the sample to be driven in and out, losing its position. To overcome this, complex software programming is required to unwind the secondary drive during rotation of the arm.

UHV Design recognizes this to be an unwanted feature and has, therefore, removed this as an issue through a unique mechanical design used on many other UHV Design manipulators over the years. In brief, this links the rotary motion of the MD64 arm to the motor mounting of the smaller MD40, mechanically unwinding the undesired motion, without the need for complex software.

Possible Actuation Methods

	Rotation Axis	Arm Extension Axis	Lift/Lower (3 Axis Only)
Manual	✔	✔	✔
Stepper Motor	✔	✔	✔
SMART Motor	✔	✔	✔
Without motor but with mounting provision	✔	✔	✔

Mating Chamber

Features

Standard 762mm/30" standard OD chamber that will accommodate all standard variants of the RTTA.
All internal welds, allowing for true UHV performance
A DN160CF (8" OD) CF port for maintenance and installation of the RTTA
6 radial ports for transfer, with options for both DN100CF (6" OD) CF and DN160CF/8"CF
DN63CF (4.5" OD) CF ports for mounting viewports (not included) for setup of sample transfer
Optional frame for easy system setup. Frame height can be customized to match your current system transfer height
Variants with diameters of 660mm/26" and up available for custom applications (must verify fit of RTTA or non-standard RTTA requested)

Key Advantages

Compact volume allowing for optimized pump performance, while allowing mounting of both 2-axis and 3-axis variants.
All internal welds, allowing for true UHV performance
Strengthened DN200CF/10"CF pumping port on the base, allowing for mounting of large turbo pumps and ion pumps
Unique safety pumping port. An internal lip in the chamber prevents any samples that get dislodged in transfer from entering the port
A removable splinter shield fits directly into the pump port for pump protection

Radial Distribution Chamber Solutions

2-AXIS RTTA

3-AXIS RTTA