Inspection system and inspection method to qualify semiconductor structures
An inspection system serves to qualify semiconductor structures. The inspection system has an ion beam source for space-resolved exposition of the structures to be qualified with an ion beam. The inspection system also includes a secondary ion detection device with a mass spectrometer. The mass spectrometer is configured to measure an ion mass to charge ratio in a given bandwidth.
1. An inspection system, comprising:
an ion beam source configured to expose semiconductor structures with an ion beam in a spatially-resolved manner; and
a secondary ion detection device comprising a mass spectrometer configured to simultaneously measure an ion mass to charge ratio in a given bandwidth,
wherein the inspection system is configured to qualify the semiconductor structures.
2. The inspection system of claim 1 , wherein the mass spectrometer is configured to continuously measure the ion mass to charge ratios in the given bandwidth.
3. The inspection system of claim 1 , wherein the secondary ion detection device comprises a secondary ion detection unit.
4. The inspection system of claim 3 , wherein the secondary ion detection unit comprises a total ion counter.
5. The inspection system of claim 3 , wherein the secondary ion detection unit comprises an extended detector array for mass filtered signals.
6. The inspection system of claim 1 , wherein the ion beam source is configured to produce a noble gas ion beam.
7. The inspection system of claim 1 , wherein the ion beam source is configured to produce a neon ion beam.
8. The inspection system of claim 1 , wherein the secondary ion detection device comprises a secondary ion transfer unit movable between:
a first position in which the transfer unit is configured to transfer secondary ions emanating from a target volume of a probe structure to be qualified to the secondary ion detection unit; and
a second position which is a neutral position.
9. The inspection system of claim 1 , wherein:
the mass spectrometer is configured to continuously measure the ion mass to charge ratios in the given bandwidth; and
the secondary ion detection device comprises a secondary ion detection unit.
10. The inspection system of claim 1 , wherein:
the mass spectrometer is configured to continuously measure the ion mass to charge ratios in the given bandwidth; and
the ion beam source is configured to produce a noble gas ion beam.
11. The inspection system of claim 1 , wherein:
the mass spectrometer is configured to continuously measure the ion mass to charge ratios in the given bandwidth; and
the secondary ion detection device comprises a secondary ion transfer unit movable between:
a first position in which the transfer unit is configured to transfer secondary ions emanating from a target volume of a probe structure to be qualified to the secondary ion detection unit; and
a second position which is a neutral position.
12. The inspection system of claim 1 , wherein:
the secondary ion detection device comprises a secondary ion detection unit; and
the ion beam source is configured to produce a noble gas ion beam.
13. The inspection system of claim 1 , wherein:
the secondary ion detection device comprises a secondary ion detection unit; and
the mass spectrometer is configured to continuously measure the ion mass to charge ratios in the given bandwidth; and
the secondary ion detection device comprises a secondary ion transfer unit movable between:
a first position in which the transfer unit is configured to transfer secondary ions emanating from a target volume of a probe structure to be qualified to the secondary ion detection unit; and
a second position which is a neutral position.
14. A method, comprising:
using the inspection system of claim 1 to qualify semiconductor structures.
15. A method, comprising:
raw review of a semiconductor structure to identify qualification volume candidates; and
detailed review of the qualification volume candidates identified in the raw review,
wherein, for each qualification volume candidate, the detailed review comprises:
spatially-resolved ion beam sputtering;
detecting secondary ions; and
within an ion mass to charge ratio bandwidth, simultaneously using mass spectrometry to continuously analyze the detected secondary ions.
16. The inspection method of claim 15 , wherein, during the detailed review, a lateral space resolution is greater than 100 nm.
17. The inspection method of claim 15 , wherein, during the spatially-resolved ion beam sputtering, the ion beam has a focal diameter of less than 5 nm.
18. The inspection method of claim 15 , comprising performing the inspection during a semiconductor production.
19. The inspection method of claim 15 , further comprising using a secondary electron microscopy image to choose at least one of the qualification candidate volumes.
20. The inspection method of claim 15 , further comprising:
using the continuous mass spectrometry of the secondary ions to reveal a material distribution; and
using a secondary electron microscope to image the material distribution.