US 8,314,410 B2 · Combination laser and charged particle beam system

Abstract

A combined laser and charged particle beam system. A pulsed laser enables milling of a sample at material removal rates several orders of magnitude larger than possible for a focused ion beam. In some embodiments, a scanning electron microscope enables high resolution imaging of the sample during laser processing. In some embodiments, a focused ion beam enables more precise milling of the sample. A method and structure for deactivating the imaging detectors during laser milling enables the removal of imaging artifacts arising from saturation of the detector due to a plasma plume generated by the laser beam. In some embodiments, two types of detectors are employed: type-1 detectors provide high gain imaging during scanning of the sample with an electron or ion beam, while type-2 detectors enable lower gain imaging and endpoint detection during laser milling.

Claims35

Dependent claims

A charged-particle beam system, comprising:

a vacuum chamber;
a workpiece support for supporting a workpiece within the vacuum chamber;
an ion beam system including an ion source for generating ions and a focusing column for forming the ions into a beam having a sub-micron diameter at the workpiece;
an electron beam system including a source for generating electrons and a focusing column for forming the electrons into a beam having a sub-micron diameter at the workpiece;
and
a laser system for operating on the workpiece in the vacuum chamber, the laser system including a lens and generating a pulsed laser beam having an energy great enough to remove material from workpiece, the laser beam being focused onto the sample by a focusing element so that the laser beam and at least one of the charged particle beams are coincident on the sample.

3 more elements

A charged-particle beam system, comprising:

a vacuum chamber;
a workpiece support for supporting a workpiece within the vacuum chamber;
an charged particle beam system including an charged particle source for generating charged particles and a focusing column for forming the charged particles into a beam having a sub-micron diameter at the workpiece;
a laser system for operating on the workpiece in the vacuum chamber, the laser system including a lens and generating a pulsed laser beam having an energy great enough to remove material from workpiece by laser beam milling;
the laser beam being focused onto the sample by a focusing element inside the vacuum chamber so that the laser beam and at least one of the charged particle beams are coincident on the sample;
a first detector for detecting secondary particles emitted from the workpiece due to the impact of the charged particle beam;
and
a first detector controller configured to deactivate the first detector before the laser beam is focused onto the sample so that the first detector will not be saturated by particles generated by laser beam milling and to reactivate the first detector after the laser beam milling is complete and the particles generated by laser milling have dissipated.

5 more elements

Dependencies are inferred from the claim text.

Combination laser and charged particle beam system

Life of this patent

Combination laser and charged particle beam system

Life of this patent

Abstract

Claims35