Method and apparatus for the characterization of a depth structure in a substrate
View Patent ↗The present invention provides a method for the characterization of a depth structure in a substrate at a surface of the substrate, in which a cutout is produced at the surface of the substrate between an imaging device and the depth structure, the cutout being spaced apart from the depth structure. A layer of the substrate, which incipiently cuts the depth structure and the cutout, is removed by means of an ion beam in order to obtain a cut area, the layer and the normal to the area of the surface of the substrate assuming an acute angle that is greater than zero. The cut area is imaged by means of the imaging device in order to characterize the depth structure.
1. A method for the characterization of a depth structure in a substrate at a surface of the substrate comprising:
producing a cutout at the surface of the substrate between an imaging device and the depth structure, the cutout being spaced apart from the depth structure;
removing a layer of the substrate, which incipiently cuts the depth structure and the cutout, by means of an ion beam to obtain a cut area, the layer and the normal to the area of the surface of the substrate assuming an acute angle that is greater than zero; and
imaging of the cut area by means of the imaging device to characterize the depth structure.
2. The method as claimed in claim 1 , in which the cutout is produced by means of an ion beam.
3. The method as claimed in claim 1 , in which the ion beam has a direction parallel to the layer.
4. The method as claimed in claim 1 , in which the cut area is imaged by scanning electron microscopy or scanning force microscopy and/or is analyzed by means of Auger electron spectroscopy, energy dispersive X-ray spectroscopy, wavelength dispersive X-ray spectroscopy or X-ray photoelectron spectroscopy.
5. The method as claimed in claim 1 , in which the producing, removing and imaging are executed multiple times to characterize the depth structure on the basis of images of a plurality of cut areas.
6. The method as claimed in claim 1 , wherein in the removing, the depth structure is lengthened in a direction parallel to the direction of the ion beam, and in which a width of the depth structure measured perpendicular to the direction of the ion beam is determined for the characterization.
7. An apparatus for the characterization of a depth structure in a substrate at a surface of the substrate, comprising:
a device for removing a layer of the substrate, which incipiently cuts the depth structure and a cutout at the surface of the substrate by means of an ion beam to obtain a cut area; and
a device for imaging the cut area through the cutout to characterize the depth structure, wherein
the removal device is formed such that the layer and the normal to the area of the surface of the substrate assume an acute angle that is greater than zero.
8. The apparatus as claimed in claim 7 , in which the removal device and the imaging device are arranged at a vacuum vessel in such a way that the removal and the imaging can be effected without moving the substrate.
9. The apparatus as claimed in claim 7 , in which the imaging device is a scanning electron microscope or a scanning force microscope or comprises a device for Auger electron spectroscopy, X-ray photoelectron spectroscopy, energy dispersive X-ray spectroscopy or wavelength dispersive X-ray spectroscopy.