CN1979750A - Non-uniform magnetic-field parallel-beam lens system - Google Patents

Abstract

The invention makes public a kind of heterogeneous magnetic field parallel bank lens system, the system includes: side magnetism yoke, vacuum box, upper magnetism yoke, upper magnetic pole, upper wire wrap, bottom wire wrap, cooling plate, bottom magnetism yoke, bottom magnetic pole, magnetism pliers. Among which, the bolt that is between the upper magnetism yoke and the bottom magnetism yoke connects with the upper magnetic pole and the bottom magnetic pole, the distance between the upper magnetic pole and the bottom magnetic pole is nonlinear; a vacuum box is placed between the upper magnetic pole and the bottom magnetic pole; the bolt at the outside of the upper magnetic pole connects with the upper wire wrap; the bolt at the outside of the bottom magnetic pole connects with the bottom wire wrap'; the upper wire wrap, the bottom wire wrap are series-wound for use; the cooling plate that are available among the upper wire wrap and the bottom wire wrap that are used for cooling the wire wrap; the bolt between the outside of the upper wire wrap and the bottom wire wrap, the upper magnetism yoke and the bottom magnetism yoke connects with the side magnetism yoke, the side magnetism, the upper magnetism yoke and the bottom magnetism yoke forms magnetic field loop; the magnetism pliers bolt is connected at the outside of the upper magnetism yoke and the bottom magnetism yoke, lies in the incidence side and emitting side of ion band, it is formed by four pieces, can reduce the edge magnetic field effect of magnet efficiently.

Description

Non-uniform magnetic-field parallel-beam lens system

Technical field

The present invention relates to a kind of parallel beam magnetic lens system, relate in particular to a kind of non-uniform magnetic-field parallel-beam lens system.

Background technology

In the existing semiconductor integrated circuit manufacturing technology, along with the development of semiconductor integrated circuit technology, integrated level is more and more higher, and circuit scale is increasing, and the unit component size is more and more littler in the circuit, and each semiconductor manufacturing equipment is had higher requirement.Ion implantor has also proposed very high requirement as one of key equipment of semiconductor ion doping processing line.Especially to the requirement of energy contamination and particle pollution,, also more and more higher to the directed requirement of injecting of line to the requirement of uniformity, repeatability.On the other hand, in order to enhance productivity, wafer size also increasing (300mm), therefore line being transferred to abreast seems on the wafer is even more important.

Dwindling and enter 180nm when following along with device feature size, ion implantation device also is subjected to very stern challenge at aspects such as bundle collimation, beam energy purity, the control of the injection degree of depth, injection repeatability, uniformity and productivity ratio, and ion implantor need adopt high inclination-angle ion injection mode.

Common ion implantor, not high to the shape need that injects ion beam, directly use static (level, vertical) scanning to inject and get final product.Along with developing rapidly of IC industry, integrated level increases, and lines attenuate, and the angle difference of ion beam directly influences the processing performance of device, so the depth of parallelism of injecting ion beam has been proposed very high requirement.The angle that needs design specialized parallel beam lens to proofread and correct ion beam.

Parallel beam can make the implant angle on the entire wafer be consistent, improve uniformity and repeatability, and can prevent that incident ion from producing channeling effect on the lattice structure of semiconductor wafer, also can make it to produce uniform needed raceway groove, therefore, parallel beam also is necessary in the angled ion implanter.

Bundle incident of non-uniform magnetic-field intermediate ion and outgoing model are as shown in Figure 1, intrafascicular heart plane (horizontal plane) is xoz, z is the beam transport direction of motion, and x is a horizontal direction, and is opposite with the beam steering direction, θ is a scanning angle, A is a sweep center point, and (X is non-homogeneous place (direction vertically penetrates paper) to B, and L1 is that scanning element is to place plane of incidence distance, H is the initial point distance of scanning element to the definition of plane of incidence magnetic pole, and L2 is the field regions width.

The condition of parallel beam is the bunch no matter how many θ is, behind the territory B of place, magnetic field, its direction of motion is parallel with the z axle, perpendicular to exit facet.

When line will be subjected to Lip river logical sequence magneticaction after θ enters field regions at an angle:

Fx?qVz.B?X (1)

Fz?qVxB?X (2)

Fx?ma _x＝m?dVx?dt 3

Fz?ma _z＝m?dVz?dt (4)

Vz?dz?dt (5)

In the formula: m is a mass of ion, and q is the ion electric weight, and Fx is the Lip river logical sequence magnetic force of x direction, and Fz is the Lip river logical sequence magnetic force of z direction, and Vz is the ion velocity of z direction, and Vx is the ion velocity of x direction, a _xBe the ion acceleration of x direction, a _zIon acceleration for the z direction.

Under the effect of Fx power, the speed of x direction reduces; Under the effect of Fz power, the speed of z direction increases.

Can obtain by formula (1), (3), (5):

Fx?qVzB?X?qB?X?dz?dt?mdVx?dt 6

m?dVx?qB?X?dz 7

(7) are carried out integration to get:

${\∫}_{\mathrm{Vx}\left(0\right)}^{\mathrm{Vx}\left(z\right)}\mathrm{mdVx}={\∫}_0^z\mathrm{qB}\left(x\right)\mathrm{dz}---\left(8\right)$

m[Vx?z-Vx?0]＝qB?x?Z 9

When Z L2, Vx z=0 could satisfy the parallel condition of vertical outgoing like this

Can obtain by (9): satisfy the magnetic field B under the parallel condition of vertical outgoing

B?x＝-Vx?0?m?qL2 (10)

As seen from Figure 1:

-Vx?0)＝Vsinθ (11)

tgθ＝(H-X?L1 12

θ＝arctg?H-X?L1 (13)

B?x＝(m?qL2)*Vsin?arctg?H-X?L1 14

Formula (14) has provided under specified criteria L1, H, the L2, under any incident angle, and the vertical Distribution of Magnetic Field of outgoing.

Ask the magnetic pole gap distance D X of satisfied (14) below

D?X?K?B?X (15)

In the formula: K is a proportionality coefficient, by the initial boundary conditional decision:

K?D ₀*B ₀ (16)

Get B by (14) ₀=(mV qL2 sin arctg H L1) (17)

Obtain non-uniform magnetic-field parallel-beam lens pole-face spacing thus:

D?X?D ₀*(sin?arctg?H?L1 sin?arctg?H-X?L1 (18)

In the formula: D ₀, H, L1 determine by light path design.

Summary of the invention

For the injection ion beam that makes ion implantor is parallel, the invention provides a kind of non-uniform magnetic-field parallel-beam lens system, this system designs according to background technology Chinese style (18).

Technical scheme of the present invention is achieved in that non-uniform magnetic-field parallel-beam lens system comprises side yoke, vacuum box, upper magnet yoke, upward magnetic pole, the bag of reaching the standard grade, the bag that rolls off the production line, coldplate, lower yoke, lower magnetic pole, magnetic clamp.

Wherein screw is connected with magnetic pole and lower magnetic pole between upper magnet yoke and the lower yoke; Distance between last magnetic pole and the lower magnetic pole is non-linear, satisfies formula (18); Place vacuum box between last magnetic pole and the lower magnetic pole, vacuum box is the ion beam passage; Last magnetic pole outside screw connects the bag of reaching the standard grade; Lower magnetic pole outside screw connects the bag that rolls off the production line; Reach the standard grade bag, the bag series connection of rolling off the production line uses, and applies constant DC stream in the online bag, produces non-uniform magnetic-field between last lower magnetic pole, satisfies formula (14); Reach the standard grade and all be useful on the coldplate of cooling line bag in the middle of bag, the bag that rolls off the production line; Reach the standard grade outside bag, the bag that rolls off the production line, screw is connected with the side yoke between upper magnet yoke and the lower yoke, and side yoke and upper magnet yoke, lower yoke constitute field circuit; Magnetism plier bolt is connected the upper magnet yoke and the lower yoke outside, is positioned at the ion beam plane of incidence and exit facet, constitutes the fringe magnetic field effect of the magnet that can reduce effectively by four.

The present invention has following superior effect:

1. the ion beam implant angle is consistent, guarantees uniformity and repeatability, and can prevent that incident ion from producing channeling effect on the lattice structure of semiconductor wafer, also can make it to produce uniform needed raceway groove.

2. the parallelism of ion beam height is controlled easily, and is simple to operate.

Description of drawings

Fig. 1 is non-uniform magnetic-field intermediate ion bundle incident of the present invention and outgoing model.

Fig. 2 is a non-uniform magnetic-field parallel-beam lens system profile of the present invention.

Fig. 3 is a non-uniform magnetic-field parallel-beam lens system partial cross sectional views of the present invention.

Wherein:

1-side yoke

The 2-vacuum box

The 3-upper magnet yoke

The last magnetic pole of 4-

The 5-bag of reaching the standard grade

The 6-coldplate

The 7-bag that rolls off the production line

The 8-lower yoke

The 9-lower magnetic pole

10-magnetic pincers

The 11-suspension ring

Embodiment

Below in conjunction with specific embodiment the present invention is described in further detail:

As shown in Figure 1, the present invention includes side yoke 1, vacuum box 2, upper magnet yoke 3, last magnetic pole 4, the bag 5 of reaching the standard grade, coldplate 6, the bag 7 that rolls off the production line, lower yoke 8, lower magnetic pole 9, magnetic pincers 10.

Wherein screw is connected with magnetic pole 4 and lower magnetic pole 9 between upper magnet yoke 3 and the lower yoke 8; Place vacuum box 2 between last magnetic pole 4 and the lower magnetic pole 9, vacuum box 2 is ion beam passages; Last magnetic 4 utmost points outside screw connects the bag 5 of reaching the standard grade; Lower magnetic pole 9 outside screws connect the bag 7 that rolls off the production line; Bag 7 series connection of reaching the standard grade and wrap 5, roll off the production line are used, and apply constant DC stream in the online bag, produce non-uniform magnetic-field between last magnetic pole 4, lower magnetic pole 9; Reach the standard grade and wrap 5, roll off the production line and wrap the coldplates 6 that all are useful on cooling line bag in the middle of 7; Reach the standard grade and wrap 5, roll off the production line and wrap 7 outsides, screw is connected with side yoke 1 between upper magnet yoke 3 and the lower yoke 8, and side yoke 1 constitutes field circuits with upper magnet yoke 3, lower yoke 8; Magnetic clamps 10 screws and is connected the upper magnet yoke 3 and lower yoke 8 outsides, constitutes the fringe magnetic field effect of the magnet that can reduce effectively by four.

Distance between last magnetic pole 4 and the lower magnetic pole 9 is non-linear, satisfies D XD ₀* (sin arctg H L1 sin arctg H-X L1, wherein intrafascicular heart plane (horizontal plane) is xoz, and z is the beam transport direction of motion, and x is a horizontal direction, and is opposite with the beam steering direction, and D X is the magnetic pole gap distance, D ₀Magnetic pole gap distance during for ion beam incident, L1 be scanning element to place plane of incidence distance, H is a scanning element to the initial point distance of plane of incidence magnetic pole definition, L2 is the field regions width, D ₀, H, L1 determine by light path design.

The present invention can also comprise base 10, and described base 10 screws are connected below the lower yoke 8.

The present invention can also comprise suspension ring 11, and described suspension ring 11 are welded on above the upper magnet yoke 3.

Specific embodiment of the present invention elaborates summary of the invention.For persons skilled in the art, any conspicuous change of under the prerequisite that does not deviate from the principle of the invention it being done all constitutes the infringement to patent of the present invention, with corresponding legal responsibilities.

Claims (4)

1, a kind of non-uniform magnetic-field parallel-beam lens system, comprise side yoke, vacuum box, upper magnet yoke, last magnetic pole, the bag of reaching the standard grade, the bag that rolls off the production line, coldplate, lower yoke, lower magnetic pole, magnetic pincers, it is characterized in that: screw is connected with magnetic pole and lower magnetic pole between upper magnet yoke and the lower yoke; Place vacuum box between last magnetic pole and the lower magnetic pole; Last magnetic pole outside screw connects the bag of reaching the standard grade; Lower magnetic pole outside screw connects the bag that rolls off the production line; Reach the standard grade bag, the bag series connection of rolling off the production line uses; Reach the standard grade and all be useful on the coldplate of cooling line bag in the middle of bag, the bag that rolls off the production line; Reach the standard grade outside bag, the bag that rolls off the production line, screw is connected with the side yoke between upper magnet yoke and the lower yoke; Magnetism plier bolt is connected the upper magnet yoke and the lower yoke outside, constitutes by four.

2, non-uniform magnetic-field parallel-beam lens system as claimed in claim 1 is characterized in that: the described distance that goes up between magnetic pole and the lower magnetic pole is non-linear, satisfies DXD ₀* (sin arctg H L1 sin arctg H-X L1, wherein the ion beam central plane is xoz, and z is the beam transport direction of motion, and x is a horizontal direction, and is opposite with the beam steering direction, and DX is the magnetic pole gap distance, D ₀Magnetic pole gap distance during for ion beam incident, L1 be scanning element to place plane of incidence distance, H is a scanning element to the initial point distance of plane of incidence magnetic pole definition, L2 is the field regions width.

3, non-uniform magnetic-field parallel-beam lens system as claimed in claim 1 is characterized in that: also comprise base, described base screw is connected below the lower yoke.

4, non-uniform magnetic-field parallel-beam lens system as claimed in claim 1 is characterized in that: also comprise suspension ring, described suspension ring are welded on above the upper magnet yoke.

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