Charged particle detection apparatus and detection method

• US 7,947,953 B2
• Filed: 10/08/2008
• Issued: 05/24/2011
• Est. Priority Date: 10/08/2008
• Status: Active Grant

• Current Assignee: ICT Integrated Circuit Testing Gesellschaft Fur Halbleiterpruftechnik mbH
• Original Assignee: ICT Integrated Circuit Testing Gesellschaft Fur Halbleiterpruftechnik mbH
• Inventors: Frosien, Juergen
• Primary Examiner(s): Vanore; David A
• Application Number:
  US12/247,849
• Publication Number:
  US 20100084553A1
• Time in Patent Office: 958 Days
• Field of Search: 250/309, 250/311
• US Class Current: 250/309
• CPC Class Codes: G01T 1/00 Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation G01T3/00, G01T5/00 take precedence

Abstract

A detection apparatus for use in a charged particle beam device is provided. The detection apparatus includes a separation field generating portion adapted to generate a separation field separating positively and negatively charged secondary particles, at least one first detector for detecting positively charged particles, at least one second detector for detecting negatively charged particles, wherein the detection apparatus is adapted to simultaneously detect the positively charged secondary particles in the at least one first detector and the negatively charged secondary particles in the at least one second detector. Further, a method of simultaneously detecting negatively and positively charged particles is provided. The method includes providing a separation field, providing at least one first detector and at least one second detector, separating the negatively charged particles from the positively charged particles in the separation field, simultaneously detecting positively charged particles with the at least one first detector and negatively charged particles with the at least one second detector.

Claims

1. Detection apparatus for use in a charged particle beam device and for simultaneous detection of negatively and positively charged particles, the detection apparatus comprising:

a separation field generating portion adapted to generate a separation field separating secondary positively and negatively charged particles;

at least one first detector for detecting positively charged particles; and

at least one second detector for detecting negatively charged particles, wherein the detection apparatus is adapted to simultaneously detect the positively charged particles in the at least one first detector and the negatively charged particles in the at least one second detector, and wherein the separation field generating portion comprises;

an electrical field generating portion adapted to generate an electrical field; and

a magnetic field generating portion adapted to generate a magnetic field that is substantially orthogonal to the electrical field at least in a separation area.

2. Detection apparatus according to claim 1, wherein the magnetic field is substantially one of a homogeneous field, a dipole field, a quadrupole field, or a higher multipole field.

3. Detection apparatus according to claim 1, wherein the electrical field is substantially one of a homogeneous field, a dipole field, a quadrupole field, or a higher multipole field.

4. Detection apparatus according to claim 1, wherein the separation field generating portion comprises:

a first electrode at least partially penetrable by the positively charged particles, the first electrode adapted to be biased with a negative voltage; and

a second electrode at least partially penetrable by the negatively charged particles, the second electrode adapted to be biased with a positive voltage.

5. Detection apparatus according claim 1, further comprising at least one of the following:

a detector aperture of the at least one first detector adapted to filter the positively charged particles according to a particle characteristic; and

a detector aperture of the second detector adapted to filter the negatively charged particles according to a particle characteristic.

6. Detection apparatus according to claim 1, further comprising:

an evaluation unit for evaluating output of the at least one first detector or of the at least one second detector or of the at least one first and the at least one second detector, wherein the at least one first detector comprises an output portion for transmitting output to the evaluation unit, and/or the at least one second detector comprises an output portion for transmitting output to the evaluation unit, and wherein the evaluation unit comprises an input portion for receiving output from the output portion of the at least one first detector and/or from the output portion of the at least one second detector.

7. Charged particle beam device, comprising a detector system, the detector system comprising:

a separation field generating portion adapted to generate a separation field separating secondary positively and negatively charged particles;

at least one first detector for detecting positively charged particles; and

at least one second detector for detecting negatively charged particles, wherein the detection apparatus is adapted to simultaneously detect the positively charged particles in the at least one first detector and the negatively charged particles in the at least one second detector, and wherein the separation field generating portion comprises;

an electrical field generating portion adapted to generate an electrical field; and

a magnetic field generating portion adapted to generate a magnetic field that is substantially orthogonal to the electrical field at least in a separation area, the charged particle beam device further comprising;

a primary charged particle beam source for generating a primary charged particle beam; and

a sample holder for holding a sample.

8. Charged particle beam device according to claim 7, wherein the separation field is further adapted to let the primary charged particle beam pass undeflected.

9. Charged particle beam device according to claim 7, further comprising beam shaping portion for shaping and/or deflecting the primary charged particle beam, the beam shaping portion being adapted to influence an impingement angle and/or an impingement spot.

10. Charged particle beam device according to claim 7, wherein the primary charged particle beam source comprises a gas field ion source.

11. Charged particle beam device according to claim 7, wherein the primary charged particle beam is an ion beam comprising ions of matter selected from the group consisting of hydrogen, helium, neon, argon, krypton, xenon and mixtures thereof.

12. Charged particle beam device according to claim 7, wherein the magnetic field is substantially one of a homogeneous field, a dipole field, a quadrupole field or a higher multipole field.

13. Charged particle beam device according to claim 7, wherein the electrical field is substantially one of a homogeneous field, a dipole field, a quadrupole field or a higher multipole field.

14. Charged particle beam device according to claim 7, wherein the detection apparatus further comprises at least one of the following:

a detector aperture of the at least one first detector adapted to filter the positively charged particles according to a particle characteristic; and

a detector aperture of the at least one second detector adapted to filter the negatively charged particles according to a particle characteristic.

15. Method for simultaneously detecting secondary negatively and positively charged particles in a charged particle beam application, the method comprising:

separating secondary negatively charged particles from secondary positively charged particles in a separation field, wherein the separation field comprises an electrical field and a magnetic field that is substantially orthogonal to the electrical field at least in a separation area; and

simultaneously detecting secondary positively charged particles with at least one first detector and secondary negatively charged particles with at least one second detector.

16. Method for simultaneously detecting secondary negatively and positively charged particles according to claim 15, wherein the electrical field is one of a homogeneous field, a dipole field, a quadrupole field or a higher multipole field.

17. Method for simultaneously detecting secondary negatively and positively charged particles according to claim 15, wherein the magnetic field is one of a homogeneous field, a dipole field, a quadrupole field or a higher multipole field.

18. Method for simultaneously detecting secondary negatively and positively charged particles according to claim 15, further comprising filtering particles according to at least one particle characteristic, the particles comprising at least one of secondary negatively charged particles and secondary positively charged particles.

19. Method for simultaneously detecting secondary negatively and positively charged particles according claim 15, further comprising evaluating a detector output of the at least one first detector and of the at least one second detector.

20. Method for imaging a sample, the method comprising:

a method for detecting secondary negatively and positively charged particles, comprising;

separating secondary negatively charged particles from secondary positively charged particles in a separation field, wherein the separation field comprises an electrical field and a magnetic field that is substantially orthogonal to the electrical field at least in a separation area; and

simultaneously detecting secondary positively charged particles with at least one first detector and secondary negatively charged particles with at least one second detector, the method for imaging a sample further comprising;

providing a sample; and

providing a primary charged particle beam, wherein the secondary negatively and positively charged particles are provided by impingement of the primary charged particle beam on the sample.

21. Method for imaging a sample according to claim 20, wherein the primary charged particle beam passes the separation field undeflected.

22. Method for imaging a sample according to claim 20, wherein the primary charged particle beam impinges the sample with an impingement angle from 0°

to 45°

.

23. Method for imaging a sample according to claim 20, wherein the primary charged particle beam is an ion beam comprising ions of matter selected from the group consisting of hydrogen, helium, neon, argon, krypton, xenon and mixtures thereof.