General Specifications | |
type of instrument |
Scanning Hall Probe Microscope with STM tip for tip-sample distance control |
sensor head specifics |
MBE grown hall cross sensor ( GaAs / AlGaAs heterostructure ) on a 2-axis tiltable sensor |
mount | |
Operation Modes | |
imaging modes |
constant height |
slope compensation |
2 axis scan plane correction |
z feedback |
STM distance tracking ( usually only for autoapproach ) |
Resolution * | |
size of Hall cross on sensor |
400 nm ( high resolution ); 250 mm ( ultra high resolution ) |
field sensitivity @ 4 K |
1500 V / AT |
noise-equivalent magnetic field ( theoretical ) |
15 nT / √Hz @ 4 K and 40 μA Hall current |
80 nT / √Hz @ 77 K and 40 μA Hall current | |
typical attainable field detection limit ( measured ) |
15 μT typ . ( bandwith 10 Hz @ frequency 277 Hz ) |
z bit resolution @ 4 K |
57 pm at 15 μm scan range |
Sample Positioning | |
total travel range |
5 x 5 x 5 mm ³ ( open loop ) |
step size |
0.05 .. 3 μm @ 300 K , 10 .. 500 nm @ 4 K |
fine scan range |
50 x 50 x 24 µ m ³ @ 300 K |
30 x 30 x 15 µ m ³ @ 4 K | |
closed loop scanning |
optional |
sample holder |
ASH / QE / 4CX quick-exchange sample holder with 8 electrical contacts , integrated heater |
calibrated temperature sensor | |
Suitable Operating Conditions | |
temperature range |
1.5 K .. 300 K ( dependent on cryostat ); mK compatible setup available on request |
magnetic field range |
0 .. 15 T + ( dependent on magnet ) |
operating pressure |
designed for He exchange gas ( vacuum compatible version down to 1E-6 mbar on request ) |
Suitable Cooling Systems | |
titanium housing diameter |
48 mm |
bore size requirement |
designed for a 2 " ( 50.8 mm ) cryostat / magnet bore |
compatible cryostats |
attoDRY1000 / 1100 / 2100 |
attoLIQUID1000 / 2000 / 3000 / 5000 | |
Electronics | |
scan controller and software |
ASC500 ( for detailed specifications please see attoCONTROL section ) |
Options | |
closed loop scanning & global sample coordinates |
interferometric encoders for scan linearization and closed loop sample navigation |
ultra-large scan range upgrade |
80 x 80 @ 300 K |
125 x 125 @ 4 K | |
in-situ inspection optics |
tip / sample monitoring via in-situ LT-LED for illumination , mirrors , lenses and CCD camera |
( outside of cryostat ) | |
field of view approx . 3 mm x 2 mm , resolution approx . 20 µ m ( depending on cryostat : | |
distance top-flange to field center | |
closed loop upgrade for coarse positioners |
resistive encoder , range 5 mm , sensor resolution approx . 200 nm , repeatability 1-2 µ m |