| 摘要 |
A method, and a scanning transmission type charged-particle microscope with a controller 10 for performing sub-surface imaging of a specimen S, comprising the following steps:
- Providing a beam B of charged particles that is directed from a source 4 along a particle-optical axis through an illuminator 6 so as to irradiate the specimen;
- Providing a detector 26,30,32,34 for detecting a flux of charged particles traversing the specimen;
- Causing said beam to follow a scan path across a surface of said specimen, and recording an output of said detector as a function of scan position, thereby acquiring a scanned charged-particle image I of the specimen;
- Repeating this procedure for different members n of an integer sequence, by choosing a value P n of a variable beam parameter P and acquiring an associated scanned image I n , thereby compiling a measurement set M = {(I n , P n )};
- Using computer processing apparatus to automatically deconvolve the measurement set M and spatially resolve it into a result set representing depth-resolved imagery of the specimen,
wherein:
- Said variable beam parameter P is focus position along said particle-optical axis;
- Said scanned image I is an integrated vector field image, obtained by;
–ª Embodying said detector to comprise a plurality of detection segments;
–ª Combining signals from different detection segments so as to produce a vector output from the detector at each scan position, and compiling this data to yield a vector field;
–ª Mathematically processing said vector field by subjecting it to a two-dimensional integration operation. |
