Figure 4
From: Room temperature in-situ measurement of the spin voltage of a BiSbTe3 thin film
Tip positioning method based on overlapping STM scans used for spin-sensitive transport measurements. (a) Using one of the STM tips, a large overview scan of the area of the sample surface in which the contacts will be positioned is acquired. The overview scan (shown partially in (c)) constitutes a map for further tip navigation. (b,c) Subsequently, all four tips are moved close to their target positions to perform small scans. Once a topographic structure from the small scan is recognized in the overview scan, the corresponding tip position within the reference map is known. With all tip positions being identified, the tips can be navigated to their desired configuration in tunnelling contact by using piezoelectric control. The exact position of each tip can then be reconfirmed by further scans before contact is finally established.
