Method for operating a particle beam microscope, particle beam microscope and computer program product
A method for operating a particle beam microscope comprises scanning an object using a particle beam and detecting electrons and x-ray radiation when scanning an object using a particle beam. Improved x-ray radiation information can be generated by combining weighted x-ray radiation information items according to the formula S e ( r → "\[Rule]" i ) = ∑ j w ( i , j ) · S ( r → "\[Rule]" j ) , wherein S({right arrow over (r)} i ) is the detected x-ray radiation intensity assigned to a location {right arrow over (r)} i . The following holds true for the weights, for example: w ( i , j ) = e - ( r → "\[Rule]" i - r → "\[Rule]" j ) 2 / σ f 2 · e - ( I ( r → "\[Rule]" i ) - I ( r → "\[Rule]" j ) ) 2 / σ g 2 , wherein I({right arrow over (r)}) represents the intensity of the detected electrons that is assigned to the location {right arrow over (r)}, and σ f and σ g are constants.
1. A method of operating a particle beam microscope, the method comprising:
directing a particle beam onto a multiplicity of locations of an object;
for each given location of the multiplicity of locations:
storing location information representing the given location onto which the particle beam is directed;
detecting electrons generated by the particle beam directed onto the given location;
storing electron radiation information representing an intensity of the detected electrons in association with the location information;
detecting x-ray radiation generated by the particle beam directed onto the given location; and
storing x-ray radiation information representing an intensity of the detected x-ray radiation in association with the location information; and
for a plurality of given locations of the multiplicity of locations:
generating improved x-ray radiation information; and
storing the improved x-ray radiation information in association with the location information representing the given location,
wherein generating the improved x-ray radiation information comprises combining a plurality of weighted pieces of x-ray radiation information, and
wherein the following holds true for each weight of weights of the x-ray radiation information used in the combining:
the weight decreases with increasing distance between the given location and a location represented by the location information associated with the weighted x-ray radiation information; and
the weight decreases with increasing absolute value of a difference between the intensity represented by the electron radiation information associated with the location information representing the given location and the intensity represented by the electron radiation information associated with the location information which is also associated with the weighted x-ray radiation information.
2. The method of claim 1 , further comprising generating a representation of the improved pieces of x-ray radiation information associated with the multiplicity of locations.
3. The method of claim 2 , further comprising classifying the improved pieces of x-ray radiation information associated with the multiplicity of locations into a plurality of groups,
wherein:
pairs of pieces of x-ray radiation information associated with a same group are more similar to one another in accordance with a predetermined similarity criterion than pairs of pieces of x-ray radiation information assigned to different groups;
pieces of x-ray radiation information associated with a same group are each represented, in the same representation, with a same representation feature; and
pieces of x-ray radiation information associated with different groups are represented, in the representation, with different representation features.
4. The method of claim 3 , wherein the representation features comprise a brightness, a colour and/or a colour saturation.
5. The method of claim 1 , wherein the x-ray radiation information associated with the location information represents an energy spectrum.
6. The method of claim 5 , wherein detecting the x-ray radiation comprises reading an energy-dispersive x-ray detector.
7. The method of claim 1 , wherein detecting the electrons comprises reading an electron detector.
8. The method of claim 7 , wherein the electron detector is a backscattered electron detector.
9. The method of claim 1 , wherein combining the plurality of weighted pieces of x-ray radiation information comprises adding weighted intensity values of detected x-ray radiation intensities.
10. The method of claim 1 , wherein:
the improved x-ray radiation information is determined according to the following equation:
S
e
(
r
→
"\[Rule]"
i
)
=
∑
j
w
(
i
,
j
)
·
S
(
r
→
"\[Rule]"
j
)
;
S e ({right arrow over (r)} i ) represents the improved x-ray radiation intensity associated with a given location {right arrow over (r)} i ;
S({right arrow over (r)} j ) represents the x-ray radiation intensity associated with a location {right arrow over (r)} j ; and
w(i,j) represents the weight.
11. The method of claim 10 , wherein:
w ( i,j )= f (| {right arrow over (r)} i −{right arrow over (r)} j |)· g (| I ( {right arrow over (r)} i )− I ( {right arrow over (r)} j )|);
I({right arrow over (r)}) represents the intensity of the detected electrons associated with the location {right arrow over (r)};
f(|{right arrow over (r)} i −{right arrow over (r)} j |) is a function which decreases with increasing distance between the locations {right arrow over (r)} i and {right arrow over (r)} j ; and
g(|I({right arrow over (r)} i )−I({right arrow over (r)} j )|) is a function which decreases with increasing absolute value of the difference between intensities of detected electrons.
12. The method of claim 11 , wherein
f
(
❘
"\[LeftBracketingBar]"
r
→
"\[Rule]"
i
-
r
→
"\[Rule]"
j
❘
"\[RightBracketingBar]"
)
=
1
C
f
e
-
(
r
→
"\[Rule]"
i
-
r
→
"\[Rule]"
j
)
2
/
σ
f
2
,
and wherein C f and σ f are parameters.
13. The method of claim 12 , wherein
g
(
❘
"\[LeftBracketingBar]"
I
(
r
→
"\[Rule]"
i
)
-
I
(
r
→
"\[Rule]"
j
)
❘
"\[RightBracketingBar]"
)
=
1
C
g
e
-
(
I
(
r
→
"\[Rule]"
i
)
-
I
(
r
→
"\[Rule]"
j
)
)
2
/
σ
g
2
,
and wherein C g and σ g are parameters.
14. The method of claim 13 , further comprising generating a representation of the improved pieces of x-ray radiation information associated with the multiplicity of locations.
15. The method of claim 14 , further comprising classifying the improved pieces of x-ray radiation information associated with the multiplicity of locations into a plurality of groups,
wherein:
pairs of pieces of x-ray radiation information associated with a same group are more similar to one another in accordance with a predetermined similarity criterion than pairs of pieces of x-ray radiation information associated with different groups;
pieces of x-ray radiation information associated with a same group are each represented, in the representation, with a same representation feature; and
pieces of x-ray radiation information associated with different groups are represented, in the representation, with different representation features.
16. The method of claim 15 , wherein the representation features comprise a brightness, a colour and/or a colour saturation.
17. The method of claim 11 , wherein
g
(
❘
"\[LeftBracketingBar]"
I
(
r
→
"\[Rule]"
i
)
-
I
(
r
→
"\[Rule]"
j
)
❘
"\[RightBracketingBar]"
)
=
1
C
g
e
-
(
I
(
r
→
"\[Rule]"
i
)
-
I
(
r
→
"\[Rule]"
j
)
)
2
/
σ
g
2
,
and C g and wherein σ g are parameters.
18. One or more machine-readable hardware storage devices comprising instructions that are executable by one or more processing devices to perform operations comprising the method of claim 1 .
19. A system comprising:
one or more processing devices; and
one or more machine-readable hardware storage devices comprising instructions that are executable by the one or more processing devices to perform operations comprising the method of claim 1 .
20. The system of claim 19 , further comprising:
a particle source configured to generate a particle beam;
an electron detector; and
an x-ray radiation detector.