Method of Processing of an Object

• US 20120145895A1
• Filed: 06/20/2011
• Published: 06/14/2012
• Est. Priority Date: 06/22/2010
• Status: Active Grant

• Current Assignee: Carl Zeiss Microscopy GmbH (Carl-Zeiss-Stiftung)
• Original Assignee: CARL Zeiss SMT GmbH (Carl-Zeiss-Stiftung)
• Inventors: BIBERGER, Josef, Pulwey, Ralph, Paluszynski, Jaroslaw, Doenitz, Dietmar, Steigerwald, Michael, Mathe, Hans
• Granted Patent: US 8,816,303 B2
• Time in Patent Office: Days
• US Class Current: 250/307
• CPC Class Codes: G01B 15/04 for measuring contours or curvatures
• CPC Class Codes: H01J 2237/2611 Stereoscopic measurements and/or imaging
• CPC Class Codes: H01J 2237/30455 Correction during exposure
• CPC Class Codes: H01J 2237/30494 Vector scan
• CPC Class Codes: H01J 2237/31749 Focused ion beam
• CPC Class Codes: H01J 2237/3175 Lithography
• CPC Class Codes: H01J 37/30 Electron-beam or ion-beam tubes for localised treatment of objects
• CPC Class Codes: H01J 37/3005 Observing the objects or the point of impact on the object
• CPC Class Codes: H01J 37/3007 Electron or ion-optical systems electron or ion-optical details H01J37/06 - H01J37/153
• CPC Class Codes: H01J 37/304 Controlling tubes by information coming from the objects or from the beam, e.g. correction signals
• CPC Class Codes: H01J 37/3056 for microworking, e.g. etching of gratings, trimming of electrical components trimming of resistors H01C17/22
• CPC Class Codes: H01J 37/3174 Particle-beam lithography, e.g. electron beam lithography

Abstract

A method of processing of an object comprises scanning a particle beam across a surface of the object and detecting electrons emerging from the object due to the scanning; determining a height difference between the surface of the object and a predetermined surface for each of plural of locations on the surface of the object based on the detected electrons; determining a processing intensity for each of the plural locations on the surface of the object based on the determined height differences; and directing a particle beam to the plural locations based on the determined processing intensities, in order to remove material from or deposit material on the object at the plural locations.

Claims

1-22. -22. (canceled)

23. A method of processing of an object, wherein the method comprises:

scanning a particle beam across a surface of the object and detecting electrons emerging from the object due to the scanning;

determining a height difference between the surface of the object and a predetermined surface for each of plural of locations on the surface of the object based on the detected electrons;

determining a processing intensity for each of the plural locations on the surface of the object based on the determined height differences; and

directing a particle beam to the plural locations based on the determined processing intensities, in order to remove material from or deposit material on the object at the plural locations.

24. The method according to claim 23, wherein the processing intensities for the plural locations on the surface of the object are determined such that at least one of the following relations is fulfilled for at least one pair of locations:

i) a beam current of the particle beam directed to a first location of the pair of locations differs by more than 10% from a beam current of the particle beam directed to a second location of the pair of locations;

ii) a dwell time in which the particle beam remains directed to the first location of the pair of locations differs by more than 10% from a dwell time in which the particle beam remains directed to the second location of the pair of locations; and

iii) a beam energy of the particle beam directed to the first location of the pair of locations differs by more than 10% from a beam energy of the particle beam directed to the second location of the pair of locations.

25. The method according to claim 23, wherein the particle beam used for the scanning is an electron beam generated by an electron beam column, and wherein the particle beam used for the removing and the depositing, respectively, of material is an ion beam generated by an ion beam column.

26. The method according to claim 23, wherein the particle beam used for the scanning is an ion beam generated by an ion beam column, and wherein the particle beam used for the removing and the depositing, respectively, of material is an ion beam generated by an ion beam column.

27. The method according to claim 23, wherein the particle beam used for the scanning is an electron beam generated by an electron beam column, and wherein the particle beam used for the removing and the depositing, respectively, of material is an electron beam generated by an electron beam column.

28. The method according to claim 23, wherein an angle between a main axis of a particle beam column used for the scanning and a main axis of a particle beam column used for the removing and the depositing, respectively, of material is greater than 40°

.

29. The method according to claim 23, wherein the object is simultaneously located within a work area of a particle column used for the scanning and a work area of a particle beam column used for the removing and the depositing, respectively, and wherein an orientation of the object relative to the particle beam column used for the removing and depositing, respectively, is changed between the scanning of the particle beam and the removing and the depositing, respectively, by less than 0.5 times an angle between a main axis of the particle beam column used for the scanning and a main axis of the particle beam column used for the removing and the depositing, respectively.

30. The method according to claim 23, wherein the object is simultaneously located within a work area of a particle column used for the scanning and a work area of a particle beam column used for the removing and the depositing, respectively, and wherein an orientation of the object relative to the particle beam column used for the removing and depositing, respectively, remains substantially unchanged between the scanning of the particle beam and the removing and the depositing, respectively.

31. The method according to claim 23, wherein the detecting of the electrons emerging from the object due to the scanning comprises a first detecting in a first angular configuration and, simultaneously, a second detecting in a second angular configuration different from the first angular configuration.

32. The method according to claim 31, wherein the first detecting is performed using a first detector and the second detecting is performed using a second detector different from the first detector.

33. The method according to claim 23, wherein the scanning of the particle beam across the surface of the object and the detecting of the electrons emerging from the object due to the scanning comprises a first scanning and detecting in a first angular configuration and a second scanning and detecting in a second angular configuration different from the first angular configuration.

34. The method according to claim 33, wherein the first scanning and detecting comprises directing of the particle beam onto the object along a first direction, wherein the second scanning and detecting comprises directing of the particle beam onto the object along a second direction, and wherein an angle between the first direction and the second direction is greater than 30 mrad.

35. The method according to claim 33, wherein the detecting of the electrons emerging from the object due to the scanning in the first angular configuration comprises detecting of electrons emitted into a first range of solid angles, wherein the detecting of the electrons emerging from the object due to the scanning in the second angular configuration comprises detecting of electrons emitted into a second range of solid angles, and wherein an angle between a main axis of the first range of solid angles and a main axis of the second range of solid angles is greater than 10°

.

36. The method according to claim 23, wherein, during the scanning of the particle beam across the surface of the object, an averaged surface of the object averaged over a surface area of more than 1.0 μ

m2 has a surface normal oriented under an angle of less than 20°

to a main axis of a particle beam column used for generating the particle beam used for the scanning.

37. The method according to claim 23, wherein, during the directing of the particle beam to the plural locations on the surface, an averaged surface of the object averaged over a surface area of more than 1.0 μ

m2 has a surface normal oriented under an angle of less than 70°

to a main axis of a particle beam column used for generating the particle beam used for the directing of the particle beam to the plural locations on the surface.

38. The method according to claim 23, further comprising supplying a process gas to the object while the particle beam is directed to the plural locations on the surface of the object.

39. The method according to claim 23, wherein a scanned region of the object comprises a first surface portion and a second surface portion, wherein the first surface portion is provided by a first material and the second surface portion is provided by a second material, and wherein the first material has an ion beam removal rate which is at least 1.5 times greater than an ion beam removal rate of the second material.

40. The method according to claim 23, wherein the directing of the particle beam to the plural locations on the surface of the object allows to achieve a surface roughness fulfilling the following relation:

RMS<

1 μ

m,

wherein RMS represents a root-mean-square value of the surface roughness determined at a length scale within a range from 0.2 μ

m to 100 μ

m is fulfilled.

41. The method according to claim 40, wherein RMS<

100 nm.

42. The method according to claim 40, wherein an area of the surface in which the surface roughness is achieved is greater than 0.1 μ

m2.

43. The method according to claim 40, wherein the surface in which the surface roughness is achieved is a flat surface.

44. The method according to claim 23, wherein the scanning of the particle beam across the surface of the object and the detecting of the electrons emerging from the object due to the scanning, the determining of the height differences, the determining of the processing intensities and the directing of the particle beam to the plural locations are repeatedly performed.

45. The method according to claim 41, wherein the scanning of the particle beam across the surface of the object and the detecting of the electrons emerging from the object due to the scanning, the determining of the height differences, the determining of the processing intensities and the directing of the particle beam to the plural locations are repeated until a maximum value of the determined height differences is less than 10 nm.

46. The method according to claim 44, wherein the scanning of the particle beam across the surface of the object and the detecting of the electrons emerging from the object due to the scanning, the determining of the height differences, the determining of the processing intensities and the directing of the particle beam to the plural locations are repeated until a surface roughness of the surface is achieved which fulfills the following relation:

RMS<

1 μ

m,

wherein RMS represents a root-mean-square value of the surface roughness determined at a length scale within a range from 0.2 μ

m to 100 μ

m.

47. A method of processing of an object, wherein the method comprises:

positioning of the object simultaneously within a work area of a particle beam column and in a work area of an ion beam column;

scanning of an electron beam generated by the electron beam column across the surface of the object and detecting electrons released by the scanning in at least two angular configurations;

determining deviations of a shape of the surface of the object from a target shape of the object based on detection signals generated in the at least two angular configurations; and

directing an ion beam onto locations of the surface of the object based on the determined deviations.