Miniature device for ultra high sensitivity and stability probing in vacuum

Patent metadata

Field	Value
Publication number	US-10520527-B2
Application number	US-201816221998-A
Country	US
Kind code	B2
Filing date	Dec 17, 2018
Priority date	Dec 15, 2017
Publication date	Dec 31, 2019
Grant date	Dec 31, 2019

Abstract

The present disclosure relates to in situ transmission electron microscope (TEM) holders with improved stability and electrical sensitivity. The holders feature a front bearing seal and a rear bearing seal which allow the holders to achieve high sensitivity, high stability, large range of motion and high vacuum isolation. The bearings use a PEEK insulating disk as a pivot point for translation and tilting motion, and use O-rings to dampen vibrations, provide electrical and vacuum insulation, and to set a grabbing force between the bearing and the probe.

First claim

What is claimed is:

1. A probe assembly ( 700 ) for a transmission electron microscope (TEM), the probe assembly ( 700 ) comprising:
a. a probe holder assembly ( 710 ), having a front end ( 712 ) and a rear end ( 714 );
b. a probe manipulator ( 720 ), coupled to the rear end ( 714 ) of the probe holder assembly ( 710 );
c. a probe ( 730 ), passing through an interior of the probe holder assembly ( 710 ) between the front end ( 712 ) and the rear end ( 714 );
d. a front bearing ( 740 ), coupling the probe ( 730 ) with the probe holder assembly ( 710 ), the front bearing ( 740 ) comprising:
i. a front insulating disk ( 742 ), having a through-hole ( 743 ) for the probe ( 730 ), the disk ( 742 ) being fixed in place within the probe holder assembly ( 710 );
ii. an internal O-ring groove ( 744 ) around an inner circumference of the through-hole ( 743 ); and
iii. a front O-ring ( 745 ) inside the groove ( 744 ), configured to seal between the groove ( 744 ) and the probe ( 730 ), wherein the front O-ring ( 745 ) has a deformation of about 8-10 percent when it is squeezed between the probe ( 730 ) and the groove ( 744 ); and

e. a rear bearing ( 750 ), coupling the probe ( 730 ) with the probe manipulator ( 720 ), the rear bearing ( 750 ) comprising:
i. a rear insulating disk ( 752 ), having a through-hole ( 753 ) for the probe ( 730 ), the disk ( 752 ) being fixed in place within the probe manipulator ( 720 );
ii. an internal O-ring groove ( 754 ) around an inner circumference of the through-hole ( 753 ); and
iii. a rear O-ring ( 755 ) inside the groove ( 754 ), configured to seal between the groove ( 754 ) and the probe ( 730 ), wherein the rear O-ring ( 755 ) has a deformation of about 14-16 percent when it is squeezed between the probe ( 730 ) and the groove ( 754 );

wherein the front ( 740 ) and rear ( 750 ) bearings are each configured to serve as a pivot point for motion of the probe ( 730 ) along an x axis and a y axis, wherein the front bearing ( 740 ) allows for slide-through motion of the probe ( 730 ) along a z-axis,
wherein the rear bearing ( 750 ) does not allow for slide-through motion of the probe ( 730 ) along a z-axis, and
wherein the bearings ( 740 , 750 ) are each configured to serve as an electrically insulating vacuum seal with vibration dampening capability.

2. The probe assembly of claim 1 , wherein the probe ( 730 ) is a scanning tunneling microscope (STM) probe.

3. The probe assembly of claim 1 , wherein the insulating disks ( 742 , 752 ) are round, oval, rectangular, square, or irregularly shaped.

4. The probe assembly of claim 1 , wherein the insulating disks ( 742 , 752 ) are polyether ether ketone (PEEK) disks.

5. The probe assembly of claim 1 , wherein the insulating disks ( 742 , 752 ) are fixed in place using epoxy or additional O-rings.

6. The probe assembly of claim 1 , wherein the ( 745 , 755 ) O-rings are low-degassing O-rings.

7. The probe assembly of claim 1 , wherein the ( 745 , 755 ) O-rings have a round, oval, square, rectangular, or irregular cross-sectional shape.

8. The probe assembly of claim 1 , wherein the ( 745 , 755 ) O-rings have a durometer hardness of about 17 on the Shore hardness scale.

9. The probe assembly of claim 1 , wherein the probe manipulator ( 720 ) is configured for coarse mechanical positioning of the probe ( 730 ).

10. The probe assembly of claim 1 , wherein the probe manipulator ( 720 ) is further coupled to a piezo tube ( 725 ) configured for fine positioning of the probe ( 730 ).

11. A probe assembly ( 700 ) for a transmission electron microscope (TEM), the probe assembly ( 700 ) comprising:
a. a probe holder assembly ( 710 ), having a front end ( 712 ) and a rear end ( 714 );
b. a probe manipulator ( 720 ), coupled to the rear end ( 714 ) of the probe holder assembly ( 710 );
c. a probe ( 730 ), passing through an interior of the probe holder assembly ( 710 ) between the front end ( 712 ) and the rear end ( 714 );
d. a front bearing ( 740 ), coupling the probe ( 730 ) with the probe holder assembly ( 710 ), the front bearing ( 740 ) comprising:
i. a through-hole ( 743 ) for the probe ( 730 ) within the probe holder assembly ( 710 );
ii. an internal O-ring groove ( 744 ) around an inner circumference of the through-hole ( 743 ); and
iii. a front O-ring ( 745 ) inside the groove ( 744 ), configured to seal between the groove ( 744 ) and the probe ( 730 ); and

e. a rear bearing ( 750 ), coupling the probe ( 730 ) with the probe manipulator ( 720 ), the rear bearing ( 750 ) comprising:
i. a through-hole ( 753 ) for the probe ( 730 ) within the probe manipulator ( 720 );
ii. an internal O-ring groove ( 754 ) around an inner circumference of the through-hole ( 753 ); and
iii. a rear O-ring ( 755 ) inside the groove ( 754 ), configured to seal between the groove ( 754 ) and the probe ( 730 );

wherein the front and rear bearings ( 740 , 750 ) are each configured to serve as a pivot point for motion of the probe ( 730 ) along an x axis and a y axis, wherein the bearings ( 740 , 750 ) are each configured to serve as an electrically insulating vacuum seal with vibration dampening capability.

12. The probe assembly of claim 11 , wherein the probe ( 730 ) is a scanning tunneling microscope (STM) probe.

13. The probe assembly of claim 11 , wherein the rear bearing ( 750 ) has a greater grabbing force on the probe ( 730 ) than the front bearing ( 740 ) has on the probe ( 730 ).

14. The probe assembly of claim 11 , wherein the front O-ring ( 745 ) has a deformation of about 8-10 percent when it is squeezed between the probe ( 730 ) and the groove ( 744 ), and the rear O-ring ( 755 ) has a deformation of about 14-16 percent when it is squeezed between the probe ( 730 ) and the groove ( 754 ).

15. The probe assembly of claim 11 , wherein the front bearing ( 740 ) allows for slide-through motion of the probe ( 730 ) along a z-axis and wherein the rear bearing ( 750 ) does not allow for slide-through motion of the probe ( 730 ) along a z-axis.

16. The probe assembly of claim 11 , wherein the front bearing ( 740 ) comprises a front insulating disk ( 742 ), having the through-hole ( 743 ) for the probe ( 730 ), the disk ( 742 ) being fixed in place within the probe holder assembly ( 710 ).

17. The probe assembly of claim 11 , wherein the rear bearing ( 750 ) comprises a rear insulating disk ( 753 ), having the through-hole ( 753 ) for the probe ( 730 ), the disk ( 742 ) being fixed in place within the probe manipulator ( 720 ).

18. A bearing ( 760 ) for a transmission electron microscope (TEM) probe, the bearing comprising:
a. an insulating disk ( 762 ), having a through-hole ( 763 ) for the probe ( 730 ), the disk ( 762 ) being fixed in place within a probe holder assembly ( 710 );
b. an internal O-ring groove ( 764 ) around an inner circumference of the through-hole ( 763 ); and
c. an O-ring ( 765 ) inside the groove ( 764 ), configured to seal between the groove ( 764 ) and the probe ( 730 ), wherein the O-ring ( 765 ) has a deformation of about 8-10 percent when it is squeezed between the probe ( 730 ) and the groove ( 764 );
wherein the bearing ( 760 ) is configured to serve as a pivot point for motion of the probe ( 730 ) along an x axis and a y axis and to allow for slide-through motion of the probe ( 730 ) along a z-axis, and
wherein the bearing ( 760 ) is configured to serve as an electrically insulating vacuum seal with vibration dampening capability.

19. The bearing of claim 18 , wherein the O-ring ( 765 ) is a low-degassing O-ring, havi

Assignees

• Univ California
• Univ Michigan Regents

Inventors

• Pan Xiaoqing
• Blum Thomas F
• Xu Mingjie
• Jokisaari Jake
• Bigelow Wilbur

Classifications

• H01J37/26

  Electron or ion microscopes; Electron or ion diffraction tubes · CPC title

• H01J2237/20207

  Tilt · CPC title

• H01J37/20 Primary

  Means for supporting or positioning the object or the material; Means for adjusting diaphragms or lenses associated with the support · CPC title

• H01J2237/2818

  Scanning tunnelling microscopes · CPC title

• H01J37/285

  Emission microscopes, e.g. field-emission microscopes · CPC title