Ion beam angle calibration and emittance measurement system for ribbon beams

1. An ion beam angle calibration and emittance measurement system, comprising:

a plate comprising an elongated slit therein, wherein the elongated slit is positioned at a rotation center of the plate and configured to allow a first beam portion to pass therethrough along a beam axis;

a beam current detector located downstream of the plate, wherein the beam current detector comprises a slit therein configured to permit a second beam portion of the first beam portion to pass therethrough, wherein the beam current detector is configured to measure a first beam current associated with the first beam portion;

a beam angle detector located downstream of the beam current detector and configured to detect a second beam current associated with the second beam portion;

wherein the plate, the beam current detector and the beam angle detector are configured to collectively rotate about the rotation center of the plate in a direction non-parallel and not co-axial with the beam axis.

2. The ion beam angle calibration and emittance measurement system of claim 1 , further comprising a controller configured to calculate an ion beam emittance and an ion beam angle as a function of a wobble angle, the first beam current and the second beam current at locations in a plane or a three dimensional space.

3. The ion beam angle calibration and emittance measurement system of claim 1 , wherein the beam current detector and the beam angle detector are collectively enclosed in a housing with a front housing face with the elongated slit that comprises the plate, wherein a first end of the housing is attached to a first end of a rotatable scan arm.

4. The ion beam angle calibration and emittance measurement system of claim 3 , further comprising an electrostatic suppressor located immediately downstream of the front housing face with the elongated slit, wherein the electrostatic suppressor is configured to prevent electrons from crossing a suppressor plane associated therewith.

5. The ion beam angle calibration and emittance measurement system of claim 1 , affixed to a scan arm,

wherein the scan arm is configured to rotate about a scan arm axis;

wherein the scan arm is connected to a rotating robotic drive arm;

wherein the scan arm is configured to be driven about the scan arm axis by a scan stepper motor; and

wherein the robotic drive arm is configured to be driven by a drive arm stepper motor about a drive arm axis.

6. The ion beam angle calibration and emittance measurement system of claim 5 ,

wherein the rotatable scan arm and the rotatable drive arm together form a robotic arm assembly; and

wherein the robotic arm assembly is configured to move a housing containing the ion beam angle calibration and emittance measurement system in a rectilinear or scanning motion in a direction orthogonal to the slit.

7. The ion beam angle calibration and emittance measurement system of claim 6 ,

wherein an emittance profiler Faraday system rotating motion is performed concurrently with the rectilinear or scanning motion.

8. The ion beam angle calibration and emittance measurement system of claim 1 , further comprising a DC servo wobble motor attached to a wobble drive crank;

wherein the wobble drive crank is attached to a housing containing the ion beam angle calibration and emittance measurement system and rotates a housing face thereof about the rotation center between minus 12 and plus 12 degrees.

9. The ion beam angle calibration and emittance measurement system of claim 1 , wherein the combined measurements produce two 3-D profiles, I(x,x′) and I(y,y′) or four 2-D profiles I(x), I(x′), I(y) and I(y′), or both.

10. The ion beam angle calibration and emittance measurement system of claim 1 , wherein a beam current for a data point is defined by:

[

ⅆ

I

ⅆ

x

]

i

=

D

i

,

3

+

D

i

,

4

S

wherein:

[dI/dx] i =the beam current for the data point;

S=slot width in inches;

D(i,j)=a resulting data array that has i rows and j columns;

D (i,3) is the column containing the beam current samples made by the profile Faraday cup; and

D (i,4) is the column containing the beam current samples made by the angle Faraday cup.

11. The ion beam angle calibration and emittance measurement system of claim 1 , wherein multiple measurements of first and second beam currents are taken at a plurality of locations varying from one another by an interval Δx, wherein the Δ x interval between samples:

Δ x i =D i,2 D i-1,2

wherein:

Δx i =the x interval between samples;

D i,2 =is a resulting data array that has i rows and 2 columns; and

D i-1,2 =is a resulting data array that has i−1 rows and 2 columns.

12. The ion beam angle calibration and emittance measurement system of claim 1 , wherein multiple measurements of first and second beam currents are taken as samples at a plurality of locations varying from one another by an interval Δx, and wherein the total beam current approximated between samples is:

ΔI

i

=

Δx

i

⁡

[

ⅆ

I

ⅆ

x

]

i

wherein:

ΔI i =the total beam current approximated between samples;

D i,2 =is a resulting data array that has i rows and 2 columns; and

D i-1,2 =is a resulting data array that has i−1 rows and 2 columns.

13. The ion beam angle calibration and emittance measurement system of claim 1 , wherein the total current contained in the beam being measured is:

It

=

∑

i

=

0

n

⁢

⁢

ΔI

i

wherein:

I t =is the total current contained in the beam being measured; and

∑

i

=

0

n

⁢

⁢

ΔI

i

=

is

⁢

⁢

the

⁢

⁢

sum

⁢

⁢

of

⁢

⁢

the

⁢

⁢

total

⁢

⁢

beam

⁢

current

⁢

⁢

from

⁢

⁢

I

i

⁢

⁢

row

⁢

⁢

equals

⁢

⁢

zero

⁢

⁢

to

⁢

⁢

i

⁢

⁢

equals

⁢

⁢

n

.

is the sum of the total beam current from I i row equals zero to i equals n.

14. The ion beam angle calibration and emittance measurement system of claim 13 , wherein the current samples contained in the matrix D k,1 are normalized using the total current as follows:

K

=

It

∑

0

k

⁢

⁢

∑

0

l

⁢

⁢

D

k

,

l

wherein:

K=is a normalization factor used to normalize the sum of the angle Faraday cup plus the sampled current in the angle Faraday cup, the factor K is necessary to add dimensions to the values dl/dx′ and dl/dy′ and is well known by those of skill in the art; and

I t =is the total current contained in the beam being measured.

15. The ion beam angle calibration and emittance measurement system of claim 14 , wherein the normalized current (Inorm) from the angle Faraday samples is:

Inorm

=

K

⁢

∑

0

k

⁢

⁢

∑

0

l

⁢

⁢

D

k

,

l

wherein:

K=is a normalization factor used to normalize the sum of the angle Faraday cup plus the sampled current in the angle Faraday cup, the factor K is necessary to add dimensions to the values dl/dx′ and dl/dy′ and is well known by those of skill in the art; and

I norm =is the normalized current (I norm ) from the angle Faraday samples.

16. The ion beam angle calibration and emittance measurement system of claim 1 , wherein the ion beam angle calibration and emittance measurement system can be moved entirely out of the path of the ion beam impacting the selected workpiece; and

the system further comprises linear actuators, linear drives, and rack and pinion drives.