PEEM Sample Environments

Samples must be ultra-high vacuum compatible. The PEEM operates at pressures better than 1x10^-9 mbar and hence any material that degasses is not allowed.

Sample surfaces must be CONDUCTIVE. There is no possibility of imaging insulating surfaces because of charging effects. Ultra-thin oxide layers on metals and doped semiconductors can be used. In case of doubt, please ask your local contact.

Samples can be cooled with liquid Nitrogen down to ~ 100 K and can be heated radiatively or with e-beam. Temperatures of approx 1000 K can be reached with radiative heating and 1900 K with e-beam flashing of thin samples. The temperature is measured either with a W/Re thermocouple type C spot-welded on a Ta in thermal contact with the backside of the sample surface or with an optical pyrometer in the preparation chamber.

The sample is mounted on customized cartridges and is kept in position with Mo-caps as shown in figure 1. The outer diameter of the cap is 14 mm and the inner is 6 mm (alternatively inner diameters of 4 and 10 mm are available; please ask your local contact for more details). Please refer to figure 1 for a schematic design or ask your local contact for more details. The thickness of the sample should not exceed 2 mm.

Figure 1: left, image of the sample cartridge. Right: schematic drawing of the range of suitable sample sizes.

Samples with a diameter smaller than 4 mm can be mounted using UHV compatible and conductive glue (usually silver paste) to a Ta foil. However, please refer to the beamline staff for more details.

CARTRIDGES

• Magnetic field (uniaxial in-plane and out-of-plane)

Figure 2: In-plane uniaxial (left) and out-of-plane (right) magnetic field cartridges.

• Electric field (out-of-plane)

Figure 3: Out-of-plane electric field cartridge with temperature control (> 90 K).

• Current pulsing (wire bonded electrical contacts)

Figure 4: Cartridges with electrical contacts. The contacts can be wire bonded directly on the 4 pillars (left) or on a printed circuit board (PCB, right). 

• High temperatures (<1900 K, see Figure 1)
• Cryogenic temperatures (>90K with temperature regulation)
• Combined excitations (to be discussed with staff)

POWER SUPPLIES (FULL REMOTE CONTROL)

• Multiplexing unit 
• Ferroelectric tester
• Keithley 2461 sourcemeter (I-V characteristics/hysteresis)
• Avtec pulse generator (10ns rise time)
• Multi-channel bipolar 

• UHV Ferrovac suitcase

Figure 5: UHV suitcase (compatible with Omicron plates).

• Inert gas suitcase (transfer from glovebox)

Figure 6: Inert gas suitcase (compatible with Elmitec cartridges). The suitcase can be fitted inside a glovebox without  the need of a docking port.

• Omicron plate adaptor (compatible with PEEM cartridges)

Figure 7: PEEM cartriges with Omicron plate adaptor.