Charged particle beam apparatus
AssigneeHitachi High-Technologies Corporation
InventorsRyo Hirano, Tsunenori Nomaguchi, Chisato Kamiya, Junichi Katane
Life of this patent
Estimating the term…
Abstract
The present invention realizes a composite charged particle beam apparatus capable of suppressing a leakage magnetic field from a pole piece forming an objective lens of an SEM with a simple structure. The charged particle beam apparatus according to the present invention obtains an ion beam observation image while passing a current to a first coil constituting the objective lens, and performs an operation of reducing the image shift by passing a current to a second coil with a plurality of current values, and determines a current to be passed to the second coil based on a difference between the operations.
Claims13
A charged particle beam apparatus for irradiating a specimen with a charged particle beam, the apparatus comprising:
- an ion beam irradiation unit that emits a focused ion beam to the specimen;
- an electron beam irradiation unit that emits an electron beam to the specimen;
- an objective lens for focusing the electron beam on the specimen;
- and
- a control unit that controls the objective lens,
- wherein the objective lens includes
- a first magnetic pole piece,
- a second magnetic pole piece that is disposed at a position further away from the electron beam path with respect to the first magnetic pole piece, and
- a first coil that is disposed between the first magnetic pole piece and the second magnetic pole piece,
- the charged particle beam apparatus further includes
- a second coil that is disposed at a position further away from the electron beam path with respect to the second magnetic pole piece,
- the control unit performs
- a first operation of acquiring an observation image of the specimen by the focused ion beam while passing a first current to the first coil, and
- a second operation of acquiring the observation image of the specimen by the focused ion beam while passing a second current to the first coil after disposing a position of the specimen at the same position as the first operation,
- the control unit passes a correction current to the second coil to generate a magnetic field that reduces a positional shift of the observation image caused by passing a current to the first coil, and
- the control unit determines the correction current based on a difference between the first operation and the second operation.
Dependencies are inferred from the claim text.