JP3103584B2 - Ion implanter - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ion implantation apparatus that scans a substrate with an ion beam and implants ions into the substrate.

(Prior Art) As shown in FIG. 11, a conventional ion implantation apparatus includes an ion source A, a mass separator B, an accelerator C, and a converging lens D.
A parallel plate electrostatic deflector E for deflecting the ion beam in the Y direction (vertical direction), a parallel plate electrostatic deflector F for deflecting the ion beam in the X direction (horizontal direction), and a substrate G
The ion beam extracted from the ion source A is converted into an ion beam composed of ions having the same mass number by the mass separator B, accelerated by the accelerator C, and converged by the converging lens D. Y with parallel plate type electrostatic deflector E
After being deflected in the direction (vertical direction), it is further deflected in the X direction (horizontal direction) by the parallel plate type electrostatic deflector F and injected into the substrate G.

Therefore, in the conventional ion implantation apparatus, first, for example, a triangular wave voltage of 167 Hz is applied to the parallel plate electrostatic deflector E to sweep and deflect the ion beam in the Y direction (vertical direction). An offset voltage for offset-deflecting the ion beam by about 7 ° and a triangular wave voltage of 833 Hz, for example, are applied to the parallel plate electrostatic deflector F to offset-deflect the ion beam, and simultaneously, in the X direction (horizontal direction). ).

(Problems to be Solved by the Invention) As described above, the conventional ion implantation apparatus sweeps and deflects the ion beam in the Y direction (vertical direction) by the parallel plate type electrostatic deflector E as described above. Although the offset deflection and the sweep deflection were performed at the same time by the deflector F, the direction of the ion beam flowing out of the parallel plate type electrostatic deflector F was not always constant. It was different depending on the location of G.

Therefore, when the diameter of the substrate G is, for example, 6 inches, the angle of incidence of the ion beam incident on the end of the substrate G is:
The angle of incidence of the ion beam incident on the center of the substrate G is 2.
A difference of 7 mm occurs, and in the case of 8 inches, the substrate G
The incident angle of the ion beam incident on the edge of the substrate G and the incident angle of the ion beam incident on the center of the substrate G had a difference of 3.6 °. When this is compared between the ends of the substrate G, when the diameter of the substrate G is 6 inches, 2.7 mm × 2 =
In the case of 8 inches, the difference is 3.6 mm x 2 = 7.2 mm.

Such a difference indicates that the conditions for the ion implantation into the substrate G are different depending on the location of the substrate G,
In particular, when the integration degree of the substrate G is increased to 4 Mbits or 16 Mbits and the size of the substrate G is shifted from 6 inches to 8 inches, ions are implanted due to shadowing, deterioration of implantation uniformity or channeling. There is a problem that the characteristics of the substrate G deteriorate.

SUMMARY OF THE INVENTION An object of the present invention is to solve the conventional problem and provide an ion implantation apparatus that makes the angle of incidence of an ion beam incident on a substrate constant without depending on the location of the substrate and does not deteriorate the characteristics of the ion-implanted substrate. To provide.

According to an embodiment of the present invention, there is provided an ion implantation apparatus configured to scan an ion beam on a substrate and implant ions into the substrate. An offset voltage that causes the central axis to be inclined at a certain angle with respect to the direction, and that deflects the ion beam by a certain angle larger than the above-mentioned certain angle at each electrode and sweeps and deflects the ion beam A first multipole electrostatic deflector configured to apply a voltage obtained by superimposing a deflection voltage on the axis of the ion beam when only the offset deflection is performed by the first multipole electrostatic deflector; And a second multipole electrostatic deflector configured to apply only a voltage for sweeping and deflecting the ion beam to each electrode. It is characterized in that the direction of the ion beam flowing out is always set at a constant angle with respect to the substrate, and ions are always implanted into the substrate from the same direction.

(Operation) In the present invention, the offset voltage for inclining the central axis of the first multipole electrostatic deflector by a certain angle and deflecting the ion beam by the same angle larger than this by a certain angle. And a deflection voltage for sweeping and deflecting the ion beam are applied to each electrode of the first multipole electrostatic deflector, and only the offset deflection is performed by the first multipole electrostatic deflector. Only a voltage for sweeping and deflecting the ion beam is applied to each electrode of the second multipole electrostatic deflector that is left on the axis of the ion beam, and the voltage of the ion beam flowing out of the second multipole electrostatic deflector is changed. Since the direction is always set at a constant angle with respect to the substrate and ions are always implanted into the substrate from the same direction, the angle of incidence of the ion beam incident on the substrate is constant without depending on the location of the substrate ,I The characteristics of the substrate that has been implanted are not reduced.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, in which 1 is an ion source, and 2 is a mass separator for separating only ions of the same mass number from an ion beam 8 extracted from the ion source 1. 3 is an accelerator for accelerating the ion beam 8 separated by the mass separator 2, 4 is a converging lens for converging the ion beam 8 accelerated by the accelerator 3, 5 is an ion beam 8 converged by the converging lens 4, A first octupole electrostatic deflector, which deflects by a fixed angle, for example, 7 °, and sweeps and deflects simultaneously in the X direction (horizontal direction) and the Y direction (vertical direction). On the other hand, the central axis is inclined at a constant angle, for example, 3.5 °, in the same plane as the offset deflection angle. Numeral 6 is disposed on the axis of the ion beam 8 when the ion beam 8 is offset and deflected by 7 ° by the first octupole electrostatic deflector 5.
The ion beam 8 swept and deflected by the first octupole electrostatic deflector 5 is further subjected to an X direction (horizontal direction) and a Y direction (vertical direction).
A second octupole electrostatic deflector, which sweeps and deflects simultaneously at a constant angle to the substrate described later from the same direction, and 7 is always the same as the second octupole electrostatic deflector 6 The substrate into which the ion beam flowing out in the direction is injected.

FIG. 2 is a perspective view showing the arrangement of the first octopole electrostatic deflector 5, the second octopole electrostatic deflector 6, and the substrate 7.

Before deciding how to apply voltages to the electrodes of the first and second octupole electrostatic deflectors 5 and 6, for convenience, a cylindrical static electrode having a radius r ₀ shown in FIG. 3 is used. Consider the electric deflector 10 and consider what voltage should be applied on its circumference to generate a uniform electric field V / r ₀ in the Y direction (vertical direction) inside the deflector 10. .

Considering a line OP forming an angle θ with respect to the X direction (horizontal direction), and assuming that the voltage at point P is φ, φ is represented by the following equation.

φ = −V / r ₀ · r ₀ sin θ = −V sin θ That is, when a voltage distribution of −V sin θ is applied to the cylindrical surface of the cylindrical electrostatic deflector 10, the Y direction (vertical direction) in the cylindrical electrostatic deflector 10 Direction), a uniform electric field V / r ₀ is generated.

Similarly, when a voltage distribution of −Ucos θ is applied on the cylindrical surface of the cylindrical electrostatic deflector 10, a uniform electric field U / r ₀ is generated in the U direction (horizontal direction) in the cylindrical electrostatic deflector 10. Become like

Therefore, as shown in FIG. 4, when a voltage of −Vsin θ−Vcos θ is applied to the cylindrical surface of the cylindrical electrostatic deflector 10, the U-direction (horizontal direction) in the cylindrical electrostatic deflector 10 uniform electric field U / r ₀ and the Y-direction uniform field E ₁ obtained by superimposing a uniform electric field V / r ₀ (vertical direction) so obtained in the.

Therefore, the voltage applied to each electrode of the first octupole electrostatic deflector 5 is determined with reference to the consideration of the voltage applied to the cylindrical surface of the cylindrical electrostatic deflector.

In this case, the eight electrodes of the first octupole electrostatic deflector 5 are cylindrically arranged at regular intervals as shown in FIG. 5, and the reference numerals 5a, 5b, 5c, 4d, 5
e, 5f, 5g, and 5h, the ion beam 8 is
A voltage for offset deflection by a certain angle in the Y-axis direction (−V direction), for example, 7 °, is applied to the electrode 5a of the first octupole electrostatic deflector 5 by V ₀ and to the electrode 5b. 0 for electrode 5c, 5d for electrode −V _{0 to} electrode 5e, to electrode 5f 0 for electrode 5g, 5h for electrode Are respectively applied. Next, the voltage for simultaneously sweeping and deflecting the ion beam 8 in the X direction (horizontal direction) and the Y direction (vertical direction) is superimposed on the voltage for offset deflection, and the first octupole electrostatic charge Deflector 5 electrode
-V to 5a, to electrode 5b -U to electrode 5c, to electrode 5d V for electrode 5e, electrode 5f U for electrode 5g, for electrode 5h Are respectively applied.

On the other hand, the eight electrodes of the second octupole electrostatic deflector 6 are also arranged at regular intervals in a cylindrical shape as shown in FIG. 6, and the reference numerals 6a and 6b are clockwise from the uppermost electrode. , 6c, 6d, 6e, 6
f, 6g, and 6h, the second octupole electrostatic deflector 6 does not offset-deflect the ion beam 8 and performs the −X ′ direction (horizontal direction) and the −Y ′ direction (vertical direction). Direction), the voltage for sweeping and deflecting the ion beam 8 is applied to the electrode 6a of the second octupole electrostatic deflector 6 by V 'and to the electrode 6b. U 'on electrode 6c, on electrode 6d -V 'on electrode 6e, on electrode 6f -U 'on electrode 6g, on electrode 6h Are respectively applied.

Since V ₀ is a voltage for offset-deflecting the ion beam 8, it is a constant value.
U 'and V' are voltages for sweeping and deflecting the ion beam 8 in the X, -X 'direction (horizontal direction) and the Y, -Y' direction (vertical direction) at the same time. .

FIG. 7 shows a trajectory when the ion beam 8 deflected by the first and second octopole electrostatic deflectors 5 and 6 is scanned on the substrate 7 as viewed from the arrow.

 Next, the operation principle will be described.

FIGS. 8 (a) and 8 (b) show the results of computer simulation of the distribution of equipotential lines on the cross section inside the octupole electrostatic deflector, which is apparent from FIGS. 8 (a) and 8 (b). In this way, a uniform parallel electric field can be generated in a portion having a cross-sectional diameter of 70%, and ions can be deflected in any direction.

FIG. 9 shows the trajectories of ions in the first octupole electrostatic deflector. The center O of the deflector is taken as the origin, the direction of the center axis of the deflector is the z axis, and the y axis is perpendicular to the z axis. Deflector length
It is assumed that a uniform offset voltage E _off parallel to the l and y axes and oriented in the −y direction is inside the deflector, and the edge effect is negligible. 1/2 · l · t on the y-axis from the center of the entrance in the yz plane
Toward the point of anα, it enters at an angle of α with the z axis,
Consider ions exiting the deflector at an angle of -α with the z axis,
If the mass is m, the charge is e, and the energy is U ₀ eV,
The equation of motion of the ion is as follows.

m · d ² y / dt ² = −eE _off (1) m · d ² z / dt ² = 0 (2) From (1), dy / dt = v ₀ sinα− e / m · E _off t (2) From dz / dt = const. = v ₀ cosα The time t ₁ required to pass through the deflector is t ₁ = l / (v ₀ cosα), and just at the center of the deflector. That is, dy / dt should be 0 at t = 1/2 · t ₁ = 1 / (2v ₀ cosα), and v ₀ sinα−e / m · E _off l / (2v ₀ cosα) = 0 Accordingly, mv ₀ ² · ² sin α · cos α = eE _off l, and since 1/2 · mv ₀ ² = eU ₀ , sin2α = E _off 1 / (2U ₀ ) (3) is obtained.

Y component of velocity when exiting the deflector is calculated using (3), the _{(dy / dt) t = t1} = -v 0 sinα Therefore the absolute value of the velocity of the ions v _0.

Next, with reference to FIG. 10, the parallelism of the final beam and the uniformity of the injection in the case of rastering using the first and second octapoles will be described.

The center O of the first multipole electrostatic deflector is taken as the origin, the center axis direction is the z-axis, and the x-axis and the y-axis are perpendicular to the z-axis. It is assumed that ions enter on a straight line (referred to as a first optical axis) that forms an angle of α with the z axis in the yz plane. In the yz plane, O 'is taken at a position advanced by L on a straight line (referred to as a second optical axis) drawn in the direction of -α with respect to the z-axis from the center of the exit end face, and The left-handed second coordinate o'-x'y'z 'is taken along the z' axis in the direction and the x 'axis parallel to the x axis.

The first multipole electrostatic deflector has an offset electric field E _off having a -y direction and a uniform raster electric field E perpendicular to the z-axis.
Are superimposed, and the edge effect of the electric field is negligible. Assuming that the x and y components of E are E _x and E _y and the unit vectors in the x, y and z directions are i, j and k, E = E _x i + E _y j. If E _off = | E _off | i, then E _off = −E _off j.

It is assumed that a uniform raster electric field E 'is applied to the second multipole electrostatic deflector perpendicular to the z' axis, and that the edge effect of the electric field is negligible. x ', y', z 'the unit vector in the direction i', j ', k' When becomes _{E '= E x' i '} = E y' j '.

The length of the first multipole electrostatic deflector is l, the length of the second multipole electrostatic deflector is l ', and the velocity of ions incident on the first multipole electrostatic deflector is v ₀ . If the mass is m, the charge is e, and the energy is U ₀ eV, the equation of motion of the ion is as follows.

In the first multipole electrostatic deflector, m · d ² x / dt ² = eE (4) m · d ² y / dt ² = eE _y −Ee _off · (5 ) M · d ² z / dt ² = 0 (6) 1/2 · mv ₀ ² = eU ₀ (7) sin2α = E _off l / (2U ₀ ) ··· (8) In the second multipole electrostatic deflector, m · d ² x '/ dt ² = eE'x ··· (9) m · d ² y' / dt ² = eE _y ′ (10) m · d ² z ′ / dt ² = 0 (11) At the exit of the first multipole electrostatic deflector, t = t ₁ = 1 / (v ₀ cosα) So, the velocity and direction of the ions at the exit are as follows:

_{(Dx / dt) out = e} / m · E x t 1 = eE x l / (mv 0 cosα) = E x lv 0 / (2U 0 cosα) = E x 2v 0 sinα / E off ((3) formula see) in the same manner _{(dy / dt) out = -v} 0 sinα + E y 2v 0 sinα / E off (dz / dt) out = v 0 cosα Thus _{(dx / dt) out = 2tanα} · E x / E off (dy / dz) _out = −tanα + 2tanα · E _y / E _off The amount of deflection at the exit of the first multipole electrostatic deflector is (4)
From (5), it can be obtained as follows.

_{Δx out = 1/2 · e} / m · E x t 1 2 = E x l 2 (4U 0 cos 2 α) Δy out = E y l 2 / (4U 0 cos 2 α) second multiplexing Gokusei electrostatic deflection velocity component of the ion at the inlet of the vessel _{is, (dx '/ dt) in} = E x lv 0 / (2U 0 cosα) (dy' / dt) in = (dy / dt) out · cosα + (dz / dt) _out · sin α = E _y lv ₀ / (2U ₀ ) (dz ′ / dt) _in = (dy / dt) _out · (−sin α) + (dz / dt) _out · cos α = v ₀ −E _y lv ₀ tan α / from (2U ₀₎ dz '/ dt in the (11) in the second multi Gokusei electrostatic deflector is equal to the value at the inlet, the time required to pass through the second multi Gokusei electrostatic deflector, t _{2 = l '/ (v 0 ·} (1-E y l tanα / (2U 0))) to become. Therefore, from (9), the velocity component of the ion in the x'-axis direction at the exit of the second multipole electrostatic deflector and the cotangent of the angle between the ion's velocity vector and the x'-axis (cota)
n) is as follows.

_{(Dx '/ dt) out =} (dx' / dt) in + e / m · E x 't 2 (dx' / dz ') out = E (x l / cosα + E x' l '/ (1-E y
l tan α / (2U))) / (2U ₀ (1-E _y l tan α / (2
U ₀ ))) Similarly, at the exit of the second multipole electrostatic deflector, the cotangent of the angle between the ion velocity vector and the y ′ axis (co
ntan) is as follows:

_{(Dy '/ dz') out} = (E y l + E y 'l' / (1-E y l tanα / (2U))) / (2U 0 (1-E y l tanα / (2U 0))) Now , and the _{E x l = -E x 'l} ' ····· (12) E y l = -E y 'l' condition that ..... (13) are satisfied.

Applying the actual numerical example in the case of an 8-inch multipole electrostatic deflector for a substrate, in the case of 200 KeV, at the right end of the board,
_{E y = 0, E x =} 669.97V / cm, l = 45cm, α = 3.5 °, in the left end of _{(dx '/ dz') out} = 0.00014085 = tan -1 0.00807 ° infrastructure, E _y = 0, E in _{x = -669.97Vcm, (dx '/} dz') out = tan -1 at the upper end of (-0.00807 °) _{infrastructure, E x = 0, E y} = 669.97V / cm at (dy '/ dz') _out = −0.0003507 = tan ^-1 (−0.02009
Ii) At the lower end of the base, similarly, (dy '/ dz') _out = tan ^-1 0.02009 ゜, ie, at the upper and lower ends of the exit of the second octapole, the beam is directed inward of 0.02 ° with respect to the optical axis, At the left and right of the second octapole exit, it goes outward in the direction of 0.008 ° with respect to the optical axis.

Next, I will show that, without any special measures such as modulating the deflection voltage according to the position of the spot on the wafer, the uniformity of implantation can theoretically be kept within a maximum deviation of 0.16%.

Assuming that the distance from the center of the exit of the first multipole electrostatic deflector to the center of the entrance of the second multipole electrostatic deflector is L, the amount of deflection at the entrance of the second multipole electrostatic deflector is as follows.

Δx _'in = Δx _out than _{2tanα · E off · L (3} ), E off = sin2α · 2U 0 / l ^{_{So, Δx' in = Exl 2 /}} (4U 0 cos 2 α) + E x lL / (2U 0 cos ^{2 α)} in the same _{manner, Δy 'in = (L +} Δy out · tanα) · 2tanα · E y / E off + Δy out · cosα = E y l 2 / (4U 0 cosα) + E y lL / (2U 0 cos 2 α ) deflection amount at the outlet of ^{_{+ E y 2 l 3 · tanα}} / (8U 0 2 cos 4 α) Therefore, the second multi Gokusei electrostatic _{deflector, Δx 'out = ΔX' in} = (dX '/ dt) in · _{t 2 +1/2 · e / m ·} E x 't 2 2 = Δx' in + E x ll '/ (2U 0 -E y l tanα) + E x' l '2 / (4U 0 (1-E y l ^{_{tanα / 2U 0) 2) Δy}} 'out = Δy' in + E y ll '/ (2U 0 -E y ltanα) + E y' l '2 / (4U 0 (1-E y l tanα / 2U 0) 2) Becomes

As actual values, E _y = 0, E _y ′ = 0, E _x = 669.87V /
cm, l = 45cm, l ' = 90cm, E x l = E x' l ', U 0 = 200Ke
V, the _{L = 65.175cm, Δx 'out =} 10.0246cm next, the _{E x = -669.97V / cm, Δx} ' the _out = _-10.0246cm.

Also, E _x = 0, E _x ′ = 0, E _y = 669.97 V / cm, E _y l =
At E _y ′ l ′, Δy ′ _out = 10.02928 cm, and at E _y = −669.97 V / cm, Δy ′ _out = 10.01353 cm, and a 0.16% asymmetry occurs at the upper and lower ends of the substrate.

To summarize the above, the central axis of the first multipole electrostatic deflector is inclined by 3.5 ° with respect to the direction of incidence of the ion beam,
Applying a voltage obtained by superimposing an offset voltage for deflecting the ion beam by the same plane angle of 7 ° and a deflection voltage for sweeping and deflecting the ion beam to each electrode of the first multipole electrostatic deflector; Only the voltage for sweeping and deflecting the ion beam is applied to each electrode of the second multipole electrostatic deflector arranged on the axis of the ion beam when only the offset deflection is performed by the first multipole electrostatic deflector. The absolute value of the product of the sweep deflection electric field of the first multipole electrostatic deflector and the length of the deflector and the product of the sweep deflection electric field of the second multipole electrostatic deflector and the length of the deflector are equal. If the signs are opposite, in the case of an actual 8-inch wafer, the parallelism of the beam incident on the wafer is
Only deviations of less than 0.02% occurred, and the maximum deviation of uniformity was also found to be within 0.16%.

In this case, x of the electric field E for sweeping deflecting the ion beam of the first multiple Gokusei electrostatic deflector, y component E _x, and E _y,
'X' of the electric field E for sweeping deflecting the ion beam of the second multi Gokusei electrostatic deflector, y 'component E _x', E _y 'is only to be added so as to satisfy the following expression.

_{E x l = E x 'l} ' ········· (12) E y l = E y 'l' ········· (13) of 8-pole electrostatic deflectors Considering the example, if the first octupole electrostatic deflector and the second octupole electrostatic deflector are geometrically similar, then in FIG. 5 and FIG. V 'and U' are equal to V and U, respectively, and V '
And V, -V 'and -V, U' and U, -U 'and -U, And the power supply of the first octupole electrostatic deflector comprises | E | = λV / d, | E ′ | = λV / d ′ when supplied from a power supply that swings around an offset voltage of | E | / | E ′ | = d ′ / d ... (14) Furthermore, since the first octupole electrostatic deflector and the second octupole electrostatic deflector are geometrically similar, the ratio of their diameters is equal to their length ratio. Therefore, d ′ / d = l ′ / l (15) From (14) and (15), | E | · l = | E ′ | = · l ′ and ( 12) and (13) are satisfied.

In the above embodiment, the number of electrodes of the first and second multipole electrostatic deflectors is eight, but the number of electrodes of the electrostatic deflector is any number as long as it is five or more. Alternatively, the trajectory of the ion beam operating on the substrate may be a polygon such as a circle or a square.

(Effects of the Invention) According to the present invention, a voltage for offset deflection of an ion beam and a voltage for sweep deflection of an ion beam are superimposed and applied to each electrode of the first multipole electrostatic deflector. And a voltage for sweeping and deflecting the ion beam to each electrode of the second multipole electrostatic deflector arranged on the axis of the ion beam deflected by the offset in the first multipole electrostatic deflector. Is applied, and the ion beam flowing out of the second multipole electrostatic deflector is always in the same direction and at a constant angle with respect to the substrate. Therefore, the incident angle of the ion beam incident on the substrate is It is constant without depending on the location of the substrate, and the performance of the ion-implanted substrate does not decrease. Further, since the multipole electrostatic deflector is used, the uniform effective range of the electric field is widened as compared with the conventional parallel plate type electrostatic deflector. The size can be reduced, and the length of the ion implanter for an 8-inch substrate can be reduced to about 6 meters. Further, the output impedance of the power supply swept by the triangular wave is R, the capacitance of the load is C, and the fundamental frequency of the triangular wave is F.
Then, the distortion of the output waveform with respect to the accurate triangular wave is F
It increases with × C × R. Since the capacitance of the load is proportional to the area of the electrode, in the case of a multipole electrostatic deflector, the width of the electrode is small, so the capacitance between the electrode and the vacuum vessel is extremely small. But it can be swept with a 1KHz triangular wave.

[Brief description of the drawings]

1 to 10 show an embodiment of the present invention.
Figure is an explanatory view showing the entire apparatus, FIG. 2 is a perspective view, FIGS. 3 and 4 is shaped cylindrical with a radius r ₀ showing an arrangement of the first and second multi-Gokusei electrostatic deflector and the substrate FIG. 5 is an explanatory view showing generation of an electric field in the electrostatic deflector, FIG. 5 is an explanatory view showing an arrangement of electrodes of the first octupole electrostatic deflector, and FIG. FIG. 7 is an explanatory view showing the arrangement of the electrodes of the deflector, FIG. 7 is an explanatory view showing the trajectory when the ion beam scans over the substrate, and FIGS. FIG. 9 is a computer simulation diagram showing the equipotential lines of FIG. 9, FIG. 9 is an explanatory diagram showing the operation principle when an ion beam is deflected by the first multipole electrostatic deflector, FIG. b) is an explanatory view showing the operation principle when the ion beam is deflected by the first and second multipole electrostatic deflectors, and FIG. 11 shows the entire conventional ion implantation apparatus. FIG. In the figure, 5 ... first multipole electrostatic deflector 5a ... electrode, 5e ... electrode 5b ... electrode, 5f ... electrode 5c ... electrode, 5g ... electrode 5d ... electrode, 5h ... Electrode 6: Second multipole electrostatic deflector 6a: Electrode, 6e: Electrode 6b: Electrode, 6f: Electrode 6c: Electrode, 6g: Electrode 6d: Electrode, 6h: Electrode 7 …… Substrate 8 …… Ion beam

Continuation of the front page (72) Inventor Takakazu Niikura 2500 Hagizono, Chigasaki-shi, Kanagawa Japan Nippon Masaki Technology Co., Ltd. (56) References JP-A 1-157047 (JP, A) (58) Fields investigated (Int .Cl. ⁷ , DB name) H01J 37/317 C23C 14/48 H01J 37/147

Claims (1)

(57) [Claims] 1. An ion implantation apparatus in which an ion beam is scanned on a substrate and ions are implanted into the substrate, wherein a central axis is inclined at a certain angle with respect to an incident direction of the ion beam. The electrode is configured to apply a voltage obtained by superimposing an offset voltage for deflecting the ion beam by a predetermined angle larger than the predetermined angle and a deflection voltage for sweeping and deflecting the ion beam. One multipole electrostatic deflector, and arranged on the axis of the ion beam when only the offset deflection is performed by the first multipole electrostatic deflector.
A second multipole electrostatic deflector configured to apply only a voltage for sweeping and deflecting the ion beam, wherein the direction of the ion beam flowing out of the second multipole electrostatic deflector is determined by the substrate. At a constant angle to
An ion implantation apparatus characterized in that ions are always implanted into a substrate from the same direction.