LOW-VOLTAGE FIELD EMISSION SCANNING ELECTRON MICROSCOPE

摘要

A microscope and a method of microscopically analyzing the surface of a sample (3) are proposed, including at least the following steps: I. effecting a relative movement between an electron emitter tip (1) and the surface of the sample so as to scan it in two lateral dimensions, using an electron emitter tip (1) with an effective emission radius of equal or less than 2nm as determined by the Fowler-Nordheim relationship; II. during this relative movement causing electrons (6) emitted from the tip (1) to impinge against the surface and secondary and/or backscattered electrons (4) to be emanating therefrom, wherein a constant potential difference is applied between the sample (3) and the tip (1), wherein a piezoelectric device is used to maintain a constant tip height relative to the scanner head (2) using a constant voltage applied to the z-axis piezo such that the distance between the sample (3) and the tip (1) is in the range of 10-70 nm; III. during this relative movement collecting the secondary and/or backscattered electrons (4) by using a detector (5,7) and/or measuring the change in field emission current; IV. processing and/or displaying the output signal from the detector (5,7) and/or the measurement of the field emission current in relation to a scanning position of the tip (1) thereby producing at least one surface topographic image.