Systems and methods for pre-aligning samples for more efficient processing of multiple samples with a Broad Ion Beam (BIB) system

Patent metadata

Field	Value
Publication number	US-12106931-B2
Application number	US-202217748972-A
Country	US
Kind code	B2
Filing date	May 19, 2022
Priority date	May 19, 2022
Publication date	Oct 1, 2024
Grant date	Oct 1, 2024

Abstract

Systems and methods for pre-aligning samples for more efficient processing of multiple samples with a BIB system according to the present invention comprises affixing a sample to an adjustable portion of a sample holder, nesting the sample holder with a first mask having a first mask edge, wherein the first mask is positioned outside of a BIB system, and aligning the sample such that it has a desired geometric relationship to the first mask edge. The first mask may be geometrically similar with a second mask within the BIB system that has a second mask edge such that the geometric relationship between the first mask edge and the sample when the sample holder is nested with the first mask is the same as the geometric relationship between the second mask edge and the sample when the sample holder is nested with the second mask.

First claim

What is claimed is:

1. A method for pre-aligning samples for more efficient processing of multiple samples with a broad ion beam (BIB) system, the method comprising the steps of:
affixing a sample to an adjustable portion of a sample holder;
nesting the sample holder with a first mask having a first mask edge, wherein the first mask is positioned outside of a broad ion beam (BIB) system;
aligning the sample such that it has a desired geometric relationship to the first mask edge; and
nesting the sample holder with a second mask having a second mask edge, wherein the second mask is positioned within a BIB system, and wherein the first mask and the second mask are geometrically similar such that the geometric relationship between the first mask edge and the sample when the sample holder is nested with the first mask is the same as the geometric relationship between the second mask edge and the sample when the sample holder is nested with the second mask.

2. The method of claim 1 , wherein when the sample holder is nested with the second mask, the sample has the desired geometric relationship with the second edge without any alignment of the sample within the BIB system.

3. The method of claim 1 , further comprising irradiating, with a broad ion beam from a BIB source component of the BIB system, a portion of the second mask and a portion of the sample with a broad ion beam to remove portions of the sample.

4. The method of claim 3 , wherein the second mask blocks a portion of the broad ion beam such that a portion of interest of the sample is not removed from the sample.

5. The method of claim 1 , wherein aligning corresponds to adjusting the adjustable portion of the sample holder so that the sample is positioned such that it has a desired geometric relationship to the first mask edge.

6. The method of claim 1 , wherein the first mask and the second mask are geometrically identical.

7. The method of claim 1 , wherein the sample is affixed to the sample holder and aligned within a closed environment.

8. The method of claim 7 , wherein the closed environment has an inert gas atmosphere.

9. The method of claim 8 , wherein the closed environment has a reduced pressure.

10. The method of claim 1 , further comprising transferring the sample holder and the aligned sample from a preparation station to a BIB system.

11. The method of claim 10 , wherein the sample holder is transferred from the preparation station to the BIB system using a transfer device comprising a sealed compartment for holding the sample holder such that the sample is sealed from the environment during transport.

12. The method of claim 10 , wherein the sample holder is transferred from the preparation station to the BIB system using a storage cassette that is configured to store multiple samples for broad ion beam (BIB) polishing, the storage cassette comprising:
a housing at least partially defining an internal storage volume;
a plurality of sample holder housings located within the internal storage volume, wherein each individual sample holder housing is configured to receive a sample holder that includes a corresponding sample for polishing in a BIB system; and
wherein the storage cassette is configured to be inserted into the BIB system, and each of the sample holder housings are further configured to allow its corresponding sample holder to be removed from the cassette when the cassette is inserted into the BIB system so that the corresponding sample can be polished by the BIB system.

13. The method of claim 12 , further comprising repeating the method for multiple samples on corresponding sample holders,
affixing an additional sample to an adjustable portion of an additional sample holder;
nesting the additional sample holder with the first mask having a first mask edge;
aligning the additional sample such that it has the desired geometric relationship to the first mask edge; and
storing the sample holder and the additional sample holder in the storage cassette for transportation to the BIB system.

14. A method for pre-aligning samples for more efficient processing of multiple samples with a broad ion beam (BIB) system, the method comprising the steps of:
affixing a sample to an adjustable portion of a sample holder;
nesting the sample holder with a first mask having a first mask edge, wherein the first mask is positioned outside of a broad ion beam (BIB) system; and
aligning the sample such that it has a desired geometric relationship to the first mask edge, wherein the first mask and a second mask positioned within the BIB system and having a second mask edge are geometrically similar such that the geometric relationship between the first mask edge and the sample when the sample holder is nested with the first mask is the same as the geometric relationship between the second mask edge and the sample when the sample holder is nested with the second mask.

15. The method of claim 14 , wherein aligning corresponds to adjusting the adjustable portion of the sample holder so that the sample is positioned such that it has a desired geometric relationship to the first mask edge, and wherein when the sample holder is nested with the second mask, the sample has the desired geometric relationship with the second edge without any alignment of the sample within the BIB system.

16. The method of claim 14 , further comprising:
transferring the sample holder and the aligned sample from a preparation station to the BIB system; and
nesting the sample holder with a second mask having the second mask edge.

17. The method of claim 16 , further comprising irradiating, with a broad ion beam from a BIB source component of the BIB system, a portion of the second mask and a portion of the sample with a broad ion beam to remove portions of the sample.

18. The method of claim 17 , wherein the sample holder is transferred from the preparation station to the BIB system using a transfer device comprising a sealed compartment for holding the sample holder such that the sample is sealed from the environment during transport.

19. The method of claim 17 , wherein the sample holder is transferred from the preparation station to the BIB system using a storage cassette that is configured to store multiple samples for broad ion beam (BIB) polishing, the storage cassette comprising:
a housing at least partially defining an internal storage volume;
a plurality of sample holder housings located within the internal storage volume, wherein each individual sample holder housing is configured to receive a sample holder that includes a corresponding sample for polishing in a BIB system; and
wherein the storage cassette is configured to be inserted into the BIB system, and each of the sample holder housings are further configured to allow its corresponding sample holder to be removed from the cassette when the cassette is inserted into the BIB system so that the corresponding sample can be polished by the BIB system.

20. The method of claim 19 , further comprising repeating the method for multiple samples on corresponding sample holders,
affixing an additional sample to an adjustable portion of an additional sample holder;
nesting the additional sample holder with the first mask having a first mask edge;
aligning the additional sample such that it has the desired geometric relationship to the first mask edge; and
storing the sample holder and the additional sample holder in the storage cassette for transportation to the BIB system.

Assignees

• Fei Co

Inventors

• Hrouzek Michal
• Novak Libor
• Vystavel Tomas
• Neelisetty Krishna Kanth
• Neuzil Jan
• Klvac Ondrej

Classifications

• H01J2237/31745

  for preparing specimen to be viewed in microscopes or analyzed in microanalysers · CPC title

• H01J2237/208

  Elements or methods for movement independent of sample stage for influencing or moving or contacting or transferring the sample or parts thereof, e.g. prober needles or transfer needles in FIB/SEM systems · CPC title

• H01J2237/2007

  Holding mechanisms · CPC title

• H01J37/3056

  for microworking, e. g. etching of gratings or trimming of electrical components · CPC title

• H01J2237/3151

  Etching · CPC title