JPS6330800A - Exb speed selector - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] (Industrial application field) The present invention uses an EXB velocity type separator.

(Prior Art) In recent years, an .r-on beam device using a field emission ion source has been developed to form a hostile probe and is used for ultrafine processing of semiconductor substrates and the like. EXB speed type separator, also called Wien filter,
The charge, mass, etc. of ions mounted on the on-beam device and emitted from the ion source: It is used for the purpose of extracting an ion beam with only a desired velocity from among ion beams with various velocity distributions. There is.

By the way, when trying to use an ion beam for NHH processing, etc., components such as a deflector for controlling the ion beam irradiation device, a lens for focusing the ion beam, etc. are required. is essential for ion beam equipment.

In ion beam equipment, in order to obtain a beam of high quality, that is, with low aberrations, it is necessary to use a focusing lens, etc.
Aligner-1 The center of the components of the device, such as the deflector, etc.
It is necessary to match the (optical axes) to the current precision, but since the drift length of the ion beam is several tens of centimeters, the optical axes must match within the order of several micrometers, so an ideal mechanical assembly is required. In reality, it is very difficult to do this, and if both the astigmatism corrector and deflector are misaligned, it will be difficult to correct the astigmatism or cause problems such as increased deflection aberration. occurs.

Furthermore, when the number of constituent members of the apparatus increases, the space is occupied accordingly, resulting in a disadvantage that the drift length of the ion beam becomes longer.

As the drift length becomes longer, the ion beam becomes more susceptible to disturbances and the space charge of the ion beam itself.Furthermore, the focusing lens also requires a lens with a long focal length commensurate with the long drift length. It also has a negative effect on the characteristics, resulting in problems such as deterioration in the quality of the ion beam.

If there are fewer components, the chances of axis misalignment problems are reduced, and the drift length can be shortened, making it less susceptible to the above-mentioned disturbances and improving optical characteristics. I can do it.

Therefore, it is strongly desired that the number of constituent members be small and small.

(Objective of the Invention) An object of the present invention is to solve the above problems, shorten the drift length of an ion beam, and provide a high-quality ion beam.

(Means for Solving the Problem) The invention shown in FIG. 1 of the present application includes electrodes that are arranged opposite to each other to form an electrostatic field; comprising magnetic poles for forming a static magnetic field; constitutes a multipole element above, and at least 24 of such multipoles are subordinated to an optical axis and a diaphragm hole disposed on the optical axis in common. all electrodes of such a multipole arranged in a connected manner,
The above object has been achieved by using an ExB speed selector which is capable of applying independent voltages to each of the magnetic poles.

Further, the invention shown in FIG. 2 of the present application includes: electrodes that are arranged opposite to each other to form an electrostatic field; and electrodes that are arranged to face each other to form a static magnetic field that intersects the electrostatic field. A multipole element having a quadrupole or more is constructed by comprising magnetic poles and ;, and it is possible to apply a voltage independently to all the electrodes and magnetic poles of the multipole element, and furthermore, the magnetic poles are arranged opposite to each other. A multipole of quadrupole or more is constructed by comprising electrodes that form an electrostatic field, and the multipole and the multipole are connected in a cascade manner by sharing an optical axis and an aperture hole disposed on the optical axis. The EXB speed selection grooves provided achieve the above objective.

(1st row of implementation) FIG. 1 shows embodiment 1'; II of the present invention.

First, the ion beam traveling direction (optical axis) is set as the Z-axis 1, and two 1,100-inch flat nonmagnetic electrodes 2.3 are placed on both sides of the optical axis.
constitute an electrode pair, and form an electric field E1 in the Y-axis direction. A magnetic pole pair is formed by two parallel flat magnetic electrodes 4.5 with the optical axis roughly sandwiched between them, and a magnetic field B1 is formed in the X-axis direction.

In this case, the magnetic field B1 is orthogonal to the electric field E1 mentioned above,
A quadrupole is formed by a pair of electrodes and a pair of magnetic poles.

6 is an aperture member, and 60 is an aperture hole disposed at a position where the aperture member 6 intersects with the optical axis Z1.

Here, by arranging a quadrupole having the same configuration as the quadrupole with the optical axis and six aperture holes in common between the quadrupole and the diaphragm member 6, the quadrupole of the two stages of sub-connected quadrupole The EXB speed selection groove of the present invention is formed.

7.8 is an electrode pair in the second stage quadrupole, 9°10 is a magnetic pole pair, the electrode pair 7.8 forms an electric field E2 in the Y-axis direction, and the magnetic pole pair 9.10 forms a magnetic field B2 in the formed in the axial direction. Reference numeral 11 indicates a sample to be irradiated with the ion beam.

Further, FIG. 2a shows a cross section of the EXB speed type classification unit on the Z plane (including the Z axis (optical axis) 1 in FIG. 1).

The operating principle is as follows.

In Figure 2, the ion beam I is inside the first stage quadrupole due to the magnetic field B1 acting in the -X direction.

(2) is deflected in the -Y direction, and the ion beam 1. Due to the difference in speed between the two, the trajectory is changed (deflected) as shown in the figure.

Here, the speed of the ion beam ■ is vI, and the speed of the ion beam ■
If vr>vn, the ion beam surface is largely deflected. Roughly speaking, if an electric field E1 acting in the -Y direction is applied, the ion beams T, II
is deflected more strongly in the -y direction by this electric field E1.

Ion beam 1. II enters the second stage quadrupole while being directed by one angle in the -Y direction by the first stage quadrupole.

If an electric field E2 acting in the +Y direction is applied to the quadrupole, the ion beam 1. II should be spaced in the +Y direction.

Here, if there is a magnetic field B2 acting in the -X direction, the difference in the degree of deflection between the ion beams I and ■ becomes even larger,
It becomes easier to separate the ion beams I and (2).

Next, by selecting an appropriate electric field E2, only the ion beam I can be passed through the aperture hole 6 and irradiated onto the sample 11, as shown in the figure.

In FIG. 2C, the velocity vI of the ion beam is v
l = (0, O, El/Bl) = (0,0°E2i
When the relationship B2> is satisfied, only the ion beam I can proceed straight, pass through the six aperture holes, and irradiate the sample 11.

In Figure 2d, the electric field E1 of the first stage quadrupole is +Y
The ion beams I and II, which are separated by the difference in velocity by the magnetic field B1 and deflected in the -Y direction, are deflected in the +Y direction by the electric field E1.

In this case as well, the same can be considered as shown in Fig. 2, and the ion beam E is incident on the second stage quadrupole while being deflected in the 10Y direction by the first stage quadrupole. When an electric field E2 acting in the -)' direction is applied to the second-stage quadrupole, the ion beams (2) and (2) are deflected in the -Y direction.

If an appropriate electric field E2 is selected here, only the ion beam I can be passed through the six aperture holes and irradiated onto the sample 11, as shown in the figure.

As described above, the magnetic field B1 of the first stage quadrupole or the magnetic field B
By controlling the electric fields E1 and E2 in the )' direction of the second-stage quadrupole with reference to both the magnetic field B2 of the first and second-stage quadrupole, only the ion beam with the desired velocity is directed to the aperture hole. The sample 11 can be scanned in the Y direction by passing six quadrupole elements. Therefore, a voltage must also be applied to the magnetic electrodes arranged in the X direction of the two-stage quadrupole to form an electric field in the X direction. For example, the sample 11 can be similarly scanned in the X direction, and by combining both, the sample 11 can be scanned in the XY plane direction with an ion beam having a desired velocity.

In this embodiment, the multipole element is described as a quadrupole, but the same effect can be achieved with an octupole. Furthermore, the effect is the same even if the magnetic pole is made of an insulator or the like, so that no voltage is applied to the magnetic pole, and an electric field is created by applying a voltage to the magnetic pole.

The second invention of the present application has the same structure as the second invention described above, and its operation is similar to that described in the description of the embodiment described above, except that the magnetic field is removed from the second stage quadrupole. It may be omitted, and the operation can be easily inferred, so the explanation will be omitted.

In this case, the principle of operation is the same whether the multipole elements are connected before or after the cascade connection or in reverse.

Furthermore, if these multipoles are used as octupole elements and the voltage application is controlled, astigmatism correction is possible, and such multipole elements may be connected in three or more stages.

(Effects of the invention) The EXB speed type separation device decoy device, astigmatism corrector, optical axis adjustment aligner, or any combination thereof of the present invention can be used in combination, and when configuring the optical system, there is no space available. It has the effect of saving energy and improving optical properties.

[Brief explanation of drawings]

FIG. 1 is an explanatory perspective view of an embodiment of the EXB speed selector of the present invention. Figures 2a, b, c, and d are sectional views of the main parts of Figure 1, for explaining the principle of operation. FIG. 3 is a sectional view of a main part of another embodiment of the E'XB speed selector of the present invention. 1...Optical axis (Z axis), 2, 3.7. 8...Nonmagnetic electrode, 4.5,
9.10...Magnetic electrode, 6...Aperture hole, 11...Sample, 60...Aperture member

Claims (2)

[Claims] (1) A quadrupole or more comprising: electrodes that are arranged to face each other to form an electrostatic field; magnetic poles that are arranged to face each other to form a static magnetic field that intersects the electrostatic field; constitute a multipole element, and at least two of the multipole elements are arranged in a cascading manner with the optical axis and the aperture hole disposed on the optical axis in common, and each of all the electrodes and magnetic poles of the multipole element is E, characterized in that voltage can be applied independently to each
×B speed sorter. (2) A quadrupole or more comprising: electrodes that are arranged to face each other to form an electrostatic field; and magnetic poles that are arranged to face each other to form a static magnetic field that intersects the electrostatic field; It constitutes a multipole element, and is capable of independently applying a voltage to each of the electrodes and magnetic poles of the multipole element, and further includes electrodes that are arranged opposite to each other to form an electrostatic field. A multipole having a quadrupole or more is formed by using the multipole, and the multipole and the multipole are arranged in a cascading manner so as to share an optical axis and an aperture hole arranged on the optical axis. Speed sorter.