A magnetic lens is disclosed, which includes: a magnetic yoke, an exciting coil and a power supply controlling system. The magnetic yoke is at outside of the exciting coil and surrounds the coil; the exciting coil is made up of litz wires; the power supply controlling system is arranged to supply power to the exciting coil and control the flow directions and magnitudes of the currents in the exciting coil. A method for controlling the magnetic lens is also disclosed.

With strength of an objective lens set to first strength, a first scanned image of a sample is produced. The strength of the objective lens is set to second strength. A rotation amount difference of a charged particle beam between the case where the strength is set to the first strength and the case where the strength is set to the second strength is specified. At the second strength, with a scanner controlled such that the rotation for canceling the rotation amount difference is supplied to the charged particle beam, a second scanned image of the sample is produced. Based on a relative positional relationship between the first and second scanned images, a deflector is controlled such that positions of the first and second scanned images coincide with each other.

A charged particle beam device includes: a charged particle source that emits a charged particle beam; a boosting electrode disposed between the charged particle source and a sample to form a path of the charged particle beam and to accelerate and decelerate the charged particle beam; a first pole piece that covers the boosting electrode; a second pole piece that covers the first pole piece; a first lens coil disposed outside the first pole piece and inside the second pole piece to form a first lens; a second lens coil disposed outside the second pole piece to form a second lens; and a control electrode formed between a distal end portion of the first pole piece and a distal end portion of the second pole piece to control an electric field formed between the sample and the distal end portion of the second pole piece.

A beam deflector includes a magnetic-flux-guiding structure which has an opening through which a beam axis extends, and at least two coils arranged at the magnetic-flux-guiding structure so that they produce a magnetic field B.sub.1 having lines passing through the two coils in succession, leave the magnetic-flux-guiding structure at a first location on a first side in relation to the beam axis, cross the beam axis at a second location which is arranged at a distance along the beam axis from the magnetic-flux-guiding structure, re-enter into the magnetic flux-guiding structure at a third location on a second side lying opposite the first side, and extend around the opening from the third location to the first location within the magnetic-flux-guiding structure.

Disclosed among other aspects is a power supply such as may be used in a charged particle inspection system. The power supply includes a direct current source such as a programmable linear current source connected to a controlled voltage source where the control signal for the controlled voltage source is derived from a measured voltage drop across the direct current source.

A beam deflector includes a magnetic-flux-guiding structure which has an opening through which a beam axis extends, and at least two coils arranged at the magnetic-flux-guiding structure so that they produce a magnetic field B.sub.1 having lines passing through the two coils in succession, leave the magnetic-flux-guiding structure at a first location on a first side in relation to the beam axis, cross the beam axis at a second location which is arranged at a distance along the beam axis from the magnetic-flux-guiding structure, re-enter into the magnetic flux-guiding structure at a third location on a second side lying opposite the first side, and extend around the opening from the third location to the first location within the magnetic-flux-guiding structure.

The present invention provides a charged particle beam apparatus capable of efficiently reducing the effect of a residual magnetic field when SEM observation is performed. The charged particle beam apparatus according to the present invention includes a first mode for passing a direct current to a second coil after turning off a first coil, and a second mode for passing an alternating current to the second coil after turning off the first coil.

An objective lens arrangement includes a first, second and third pole pieces, each being substantially rotationally symmetric. The first, second and third pole pieces are disposed on a same side of an object plane. An end of the first pole piece is separated from an end of the second pole piece to form a first gap, and an end of the third pole piece is separated from an end of the second pole piece to form a second gap. A first excitation coil generates a focusing magnetic field in the first gap, and a second excitation coil generates a compensating magnetic field in the second gap. First and second power supplies supply current to the first and second excitation coils, respectively. A magnetic flux generated in the second pole piece is oriented in a same direction as a magnetic flux generated in the second pole piece.

There is provided a deflector that produces only a weak resulting combined hexapole field. The deflector (100) has first to sixth coils (11-16). The first to third coils (11-13) are equal in direction of energization. The fourth to sixth coils (14-16) are equal in direction of energization. The first coil (11) and fourth coil (14) are opposite in direction of energization. The first, third, fourth, and sixth coils (11, 13, 14, 16) are equal in electromotive force. The second coil (12) is equal in electromotive force to the fifth coil (15) and twice the electromotive force of the first coil (11).

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.