Portable scanning electron microscope

Abstract

One embodiment relates to a portable scanning electron microscope (SEM) system. The system includes a portable SEM device including a CRT-type gun and deflectors to generate and scan the electron beam. Another embodiment relates to a portable SEM device which includes a CRT-type gun and deflectors to generate and scan the electron beam, a chamber through which the electron beam is scanned, and a detector in the chamber for detecting radiation emitted as a result of scanning the electron beam. Another embodiment relates to a method of obtaining an electron beam image of a surface of a bulk specimen where a portable SEM device is moved to the bulk specimen. Other embodiments and features are also disclosed.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a high-speed two-dimensional scanning apparatus for automated electron beam inspection in accordance with an embodiment of the invention.

FIG. 2 is a schematic diagram of a first high-speed one-dimensional scanning apparatus for use with a one-dimensional moving stage in accordance with an embodiment of the invention.

FIG. 3 is a schematic diagram of a second high-speed one-dimensional scanning apparatus for use with a one-dimensional moving stage in accordance with an embodiment of the invention.

FIG. 4 is a schematic diagram of a high-speed swath scan of a wafer using a spiral path in accordance with an embodiment of the invention.

FIG. 5A is a schematic diagram of a low-vibration two-dimensional scanning apparatus in accordance with an embodiment of the invention.

FIG. 5B is a schematic diagram of a low-vibration two-dimensional scanning apparatus in accordance with another embodiment of the invention.

FIG. 6 is a top-view diagram of a support piece of the low-vibration two-dimensional scanning apparatus in accordance with an embodiment of the invention.

FIG. 7 is a schematic diagram of a CRT-type e-beam column in accordance with an embodiment of the invention.

FIG. 8 is a top-view diagram of a conductive plate within the CRT-type e-beam column in accordance with an embodiment of the invention.

FIG. 9A is a schematic diagram of a portable SEM system with a wired data interface in accordance with an embodiment of the invention.

FIG. 9B is a schematic diagram of a portable SEM system with a wireless data interface in accordance with an embodiment of the invention.

FIG. 10A is a schematic diagram of a portable SEM device with a rapid access specimen holder in accordance with an embodiment of the invention.

FIG. 10B is a schematic diagram of a portable SEM device with an environmental interface in accordance with an embodiment of the invention.

FIG. 11 is a schematic diagram of a portable SEM system with a rack-and-pinion z-stage in accordance with an embodiment of the invention.

FIG. 12 is a schematic diagram of a combination electron microscope and optical microscope in accordance with an embodiment of the invention.

Claims

1. A portable scanning electron microscope (SEM) system, the system comprising a portable SEM device including a CRT-type gun and deflectors to generate and scan the electron beam.

2. The portable SEM system of claim 1, further comprising a pump unit connected to the portable SEM device, wherein the pump unit provides vacuum pumping for the portable SEM device.

3. The portable SEM system of claim 2, further comprising a laptop computer configured to receive electron image data from the portable SEM device by way of a universal serial bus interface.

4. The portable SEM system of claim 2, further comprising a laptop computer configured to receive electron image data from the portable SEM device by way of a wireless interface.

5. The portable SEM system of claim 1, wherein the CRT-type gun comprises a series of metal plates supported by and separated by insulating material.

6. A portable scanning electron microscope (SEM) device, the device comprising: a CRT-type gun and deflectors to generate and scan the electron beam;a chamber through which the electron beam is scanned; anda detector in the chamber for detecting radiation emitted as a result of scanning the electron beam.

7. The portable SEM device of claim 6, wherein the CRT-type gun comprises a series of metal plates supported by and separated by insulating material.

8. The portable SEM device of claim 6, wherein a steel case encloses the chamber.

9. The portable SEM device of claim 6, wherein the detector comprises an electron detector.

10. The portable SEM device of claim 6, wherein the detector comprises an x-ray detector.

11. The portable SEM device of claim 6, further comprising: a vacuum detector in the chamber; anda switch for turning off power to the CRT-type gun if insufficient vacuum is detected.

12. The portable SEM device of claim 6, further comprising: a detachable specimen holder; anda mechanical interface for coupling the specimen holder to the chamber.

13. The portable SEM device of claim 6, further comprising an environmental interface at one end of the chamber for use in direct examination of a surface of a bulk specimen.

14. The portable SEM device of claim 13, wherein the environmental interface comprises a mechanical seal.

15. The portable SEM device of claim 13, wherein the environmental interface comprises an air seal.

16. A method of obtaining an electron beam image of a surface of a bulk specimen, the method comprising: moving a portable scanning electron microscope (SEM) device to the bulk specimen;placing the portable SEM device in contact with the surface of the bulk specimen in a way such that an environmental seal is formed between the surface and a chamber of the SEM device; andscanning an electron beam across an area of the surface; anddetecting radiation emitted as a result of the scanning; andforming the electron beam image of the area based on the detected radiation.

17. A portable scanning electron microscope (SEM) apparatus, the apparatus comprising: an SEM column;a vacuum pump coupled to the SEM column;a sample holder; anda z-stage configured to control up-and-down movement between an SEM column and a sample holder.

18. The portable SEM apparatus of claim 17, wherein the z-stage comprises a mechanism from a group consisting of a rack-and-pinion mechanism, a friction mechanism, a roller-bearing mechanism, and a screw mechanism.

19. The portable SEM apparatus of claim 17, further comprising: a vacuum interlock which is engaged when the SEM column is moved within a predetermined distance from the sample holder and which is disengaged when the SEM column is moved outside the predetermined distance from the sample holder.

20. The portable SEM apparatus of claim 19, further comprising a gate valve between upper and lower compartments of the SEM column, said gate valve being configured to be opened when the vacuum interlock is engaged and to be closed when the vacuum interlock is disengaged.

21. A combined electron microscope and optical microscope apparatus, the combined apparatus comprising: a transparent slide for holding a specimen;an electron microscope configured to image the specimen from one side of the slide; andan optical microscope configured to image the specimen from an opposite side of the slide.

22. The apparatus of claim 21, further comprising: a seal ring configured to seal an interface between the electron microscope and the slide.

23. The apparatus of claim 22, further comprising: a vacuum interlock which is engaged when the SEM column is moved within a predetermined distance from the sample holder and which is disengaged when the SEM column is moved outside the predetermined distance from the sample holder.