| 摘要 |
A sample (1) is mounted on a support table (2,3) adjacent a probe (5) of a scanning tunnelling microscope, the support table (2,3) permitting the sample (1) to move relative to the probe (5). The probe (5) is also movable in a direction generally perpendicular to the sample surface, between a withdrawn position and a scanning separation. A scanning electron microscope (10) is located adjacent the sample (1) and probe (5), and its electron beam (11) scans both the sample (1) and the probe (5) and generates an image on a display (16a) from electrons from the sample detected by a detector (12). In order that that operator can position the probe (5) on a target of a sample (1), for scanning by the probe (5), a marker (18) is generated on the display (16a) by a graphics display unit (17), which marker (18) indicates the probe-to-sample separation (dL) and preferably indicates the probe-to-sample approach point and the direction of movement of the probe (5) towards the sample (1). The graphics display unit (17) may alternatively, or in addition, generate a marker (19) representing the scan area of the probe (5) when it is moved to a scanning separation from the sample (1). <IMAGE> |
