CN101153855A - Sample bench - Google Patents
Sample bench Download PDFInfo
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- CN101153855A CN101153855A CNA2006101169046A CN200610116904A CN101153855A CN 101153855 A CN101153855 A CN 101153855A CN A2006101169046 A CNA2006101169046 A CN A2006101169046A CN 200610116904 A CN200610116904 A CN 200610116904A CN 101153855 A CN101153855 A CN 101153855A
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- sample bench
- objective table
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Abstract
A sample table used in section analysis of focused ion beam comprises a support bar and an object stage, wherein, the object stage comprises a first carrying surface connected with the support bar. The invention is characterized in that the object stage also comprises at least one second carrying surface intersected with the first carrying surface. The object stage can be used in section analysis equipment of focused ion beam for preparing an inclined section.
Description
Technical field
The present invention relates to technical field of manufacturing semiconductors, particularly a kind of sample bench that is used for the focused particle beam fractograph analysis.
Background technology
(Focused Ion Beam FIB) can be used for integrated circuit (IC) chip is done section (cross section) analysis, with the defective in observation and the definite chip focused ion beam.Its cardinal principle is: the ion that ion gun is produced (mainly is to sow Ga
+) quicken then to use electronic lens focusing, the ion of high energy and high speed is got to assigned address on the chip, and the chip surface material is removed the generation section, aids in scanning electron microscope (SEM), can observe the defective in each tomography in the chip.Number of patent application is that 99102770.1 Chinese patent discloses a kind of FIB equipment.As shown in Figure 1, described FIB equipment generally comprises ion gun 100, ion beam extraction electrode 102, electrostatic lens 104, deflecting electrode 106 electrostatic lens 108 and sample bench 110, and sample 112, ion beam 101 is drawn from ion gun after quicken to reach sample 112 surfaces.Its concrete way is as follows: as shown in Figure 2, at first prepare sample, described sample comprises the device layer 202 on substrate 200 and the described substrate, described sample is carried out surface treatment produce discharge (charging) to prevent ion beam and surface, causes the image drift.As shown in Figure 3, described sample is placed sample bench, determine the point of contact, regulate focused ion beam 204, in sample, etch section 206 perpendicular to sample surfaces by deflecting electrode.Described section is cleaned (clean up).As shown in Figure 4, observe with 208 pairs of described sections of SEM electron beam.
Sample bench structure in the existing FIB equipment as shown in Figure 5, the objective table 301 that comprises a support bar 300 and a thin discs shape, described objective table 301 has a circular flat loading surface 302, and wherein, described support bar 300 vertical fixing are in centre position, described objective table 301 back side.Described support bar 300 be used for sample bench be fixed in described FIB equipment FIB under, described loading surface 302 vertical planes are to described FIB.Thereby sample is positioned on the sample bench of above-mentioned FIB equipment, can produce section perpendicular to sample surfaces.
There is following defective in the existing sample bench that is used for producing sample section: have structure such as connection plug, contact plunger when sample and need be when described connection plug or the section of contact plunger position produce section, sample is positioned on the sample bench, the energetic ion of described ion beam can be punched the bottom of described connection plug or contact plunger and produce slot-shaped defective, thereby the introduction noise causes and can not determine when observing with SEM that defective is that production technology causes or this preparation process produces.As shown in Figure 6, to having connecting hole 402 samples 400 when doing fractograph analysis, FIB404 prepares sample section perpendicular to described sample 400 surfaces, because the conductive material of filling in the connecting hole 402 has different density and hardnesses with other dielectric layer on every side, at high energy ion beam when described connecting hole 402 downward etchings generate sections, the ion beam of high energy can be punched the bottom of described connecting hole 402, generate the slit defective in described connecting hole 402 bottoms, thereby can cause damage to produce into defective the device layer of connecting hole 402 bottoms.Fig. 7 is the SEM photo of the slit defective 406 of FIB ion beam generation.
Summary of the invention
The invention provides a kind of sample bench that is used for the focused ion beam fractograph analysis, produce the problem of slit defective when preparing sample section with focused ion beam to solve on existing sample bench.
For achieving the above object, a kind of sample bench provided by the invention, be applied to the focused ion beam fractograph analysis, comprise support bar and objective table, described objective table comprises first loading surface that is connected with described support bar, and described objective table also comprises second loading surface that intersects with described first loading surface at least.
Described first loading surface and second loading surface are the plane, and the angle of cut is 140～179 degree.
Described objective table is projected as circle, ellipse or polygon along described support bar direction.
Described first loading surface and second loading surface are that the plane is semicircle or arc.
The another kind of sample bench that has the relevant art feature with the present invention, comprise support bar and objective table, described objective table comprises first loading surface that is connected with described support bar, and described objective table also comprises second loading surface and the 3rd loading surface that intersects with described first loading surface at least; On described first loading surface and/or the 3rd loading surface, be formed with groove.
The corresponding loading surface with it in the bottom surface of described groove is parallel.
The angle of cut of described second loading surface, the 3rd loading surface and described first loading surface is 140 to 179 degree.
The another kind of sample bench that has the relevant art feature with the present invention, comprise support bar and objective table, described objective table comprises first loading surface that is connected with described support bar, and described objective table also comprises second loading surface and the 3rd loading surface that intersects with described first loading surface at least; On described first loading surface and/or the 3rd loading surface, be formed with clamping plate.
Described clamping plate have screw, have screw in described screw.
Compared with prior art, the present invention has the following advantages:
The objective table of sample bench of the present invention has the loading surface of inclination, chip is positioned on the described inclination loading surface when forming section with focused ion beam, the direction of contact plug or attachment plug has an angle in the direction of ion beam and the described chip, avoided ion beam that the direct bombardment of contact plug in the chip or attachment plug bottom is formed the slit defective, thereby form damage, improved specimen preparation and observed the accuracy that detects lower floor's device layer.
The loading surface of objective table of the present invention also has the groove and the clamping plate of vertical fixed chip, can be used for preparing the horizontal section of chip, thereby the horizontal section of chip is carried out imaging observation.
Description of drawings
Fig. 1 is existing a kind of focused ion beam principle schematic;
Fig. 2 is a slice sample cross-section synoptic diagram;
Fig. 3 is the existing synoptic diagram for preparing sample with focused ion beam;
Fig. 4 is existing synoptic diagram with the sem observation sample section;
Fig. 5 is the existing sample bench skeleton view that is used for focused ion beam fractograph analysis device;
Fig. 6 is the existing synoptic diagram that has the sample of connection plug or contact plunger with the focused ion beam preparation;
Fig. 7 is the existing defective synoptic diagram that has the sample generation of connection plug or contact plunger with the focused ion beam preparation;
Fig. 8 is the front elevation according to the sample bench of first embodiment of the invention;
Fig. 9 is that sample bench shown in Figure 8 is along the AA1 diagrammatic cross-section;
Figure 10 is the synoptic diagram that sample bench shown in Figure 8 is placed sample;
Figure 11 is the front elevation according to the sample bench of second embodiment of the invention;
Figure 12 is the diagrammatic cross-section of sample bench shown in Figure 11 along AA1;
Figure 13 is the diagrammatic cross-section of sample bench shown in Figure 11 along BB1;
Figure 14 is the synoptic diagram of placing at the sample of sample bench shown in Figure 12;
Figure 15 is according to the front elevation of the sample bench of third embodiment of the invention;
Figure 16 is that sample bench shown in Figure 15 is along the AA1 diagrammatic cross-section;
Figure 17 is that sample bench shown in Figure 15 is along the BB1 diagrammatic cross-section;
Figure 18 adopts the focused ion beam preparation of sample bench of the present invention to have the synoptic diagram of the sample of connection plug or contact plunger;
Figure 19 is for using the sample section SEM photo that have connection plug or contact plug of focused ion beam in sample bench preparation of the present invention.
Embodiment
For above-mentioned purpose of the present invention, feature and advantage can be become apparent more, the specific embodiment of the present invention is described in detail below in conjunction with accompanying drawing.
(Focused Ion Beam, FIB) ion that ion gun is produced (mainly is to sow Ga to focused ion beam
+) quickening the back by getting to the chip sample surface behind the electronic lens focusing, the ion of high energy and high speed can remove the chip surface material and produce section, aids in scanning electron microscope, can observe the situation of chip internal, for example defective.Use focused ion beam sample is carried out defect analysis, at first the sample thin slice to be positioned on the sample bench, sample bench is placed below the described focused ion beam then, the ion of high energy and high speed is got to sample surfaces and is produced section, because prior art is subject to the plane surface restriction of sample bench, after sample is positioned on the sample bench, thereby ion beam can only vertically be got to sample surfaces formation vertical profile.Propose a kind of sample bench among the present invention, in the time of should not preparing sample section with vertical ion beam when containing vertical stratification such as contact plunger and connection plug in the chip sample, sample can be positioned over inclined surface, and then carry out specimen preparation with inclined surface.Like this, ion beam can be got to chip surface with the angle of an inclination, departs from because the direction of the direction of ion beam bombardment sample and contact plunger or connection plug has, thereby can not cause damage to chip.
The sample bench that is applied to the focused ion beam fractograph analysis provided by the invention comprises support bar and objective table, and described objective table is except comprising first loading surface that is connected with described support bar, also comprises second loading surface that intersects with described first loading surface at least.Described support bar vertical fixing is in the back side of described first loading surface, described second loading surface and described first loading surface intersect, the angle of cut is 140～179 degree, and described objective table can also have the 3rd loading surface, the 4th loading surface, as required different angles can be set.When being applied to specimen preparation, when not having vertical stratifications such as contact plug when sample chip to be prepared, described chip can be positioned on first loading surface and form vertical profile, when having vertical stratification such as contact plug or connecting hole when chip to be prepared, chip can be positioned on second loading surface of inclination or third and fourth loading surface and form the section of inclination.Described loading surface is generally the plane, and described loading surface can be semicircle or arc, and described loading surface also can be a plane polygon.
Sample bench provided by the invention can also have the loading surface of a plurality of inclinations, can be formed with groove or clamping plate on described loading surface, and described groove or clamping plate are used for chip is vertically placed, and vertically the chip of placing can be used to observe the transversal section.For ease of fixed chip, described clamping plate are generally two, and described clamping plate have screw, in described screw screw are housed, and vertical chip can be fixed on the loading surface by two screw extruding.
Below in conjunction with accompanying drawing embodiment of the present invention is described in detail.
Fig. 8 is the front elevation according to the sample bench of first embodiment of the invention; Fig. 9 is that sample bench shown in Figure 8 is along the AA1 diagrammatic cross-section; Figure 10 is the synoptic diagram that sample bench sample shown in Figure 8 is placed.
As shown in Figure 8, the objective table 500 of described sample bench comprises the first crossing loading surface 502 and second loading surface 504, described first loading surface 502 and second loading surface 504 can be semicircle, arc or its polygon, and first loading surface 502 described in the present embodiment and second loading surface 504 are for being semicircle.
As shown in Figure 9, described sample bench also comprises support bar 501, described objective table 500 comprises first loading surface 502 and second loading surface 504, wherein said first loading surface 502 and second loading surface 504 are the plane semicircle, and described first loading surface 502 and second loading surface, 504 angles of cut 503 are 140～179 degree.Described support bar 501 is fixed in described first loading surface 502 back sides.
As shown in figure 10, the said sample platform is applied to the focused ion beam fractograph analysis.At first, the support bar 501 of described sample bench is fixed in the section analysis equipment of focused ion beam, described first loading surface 502 is placed in horizontal direction, described second loading surface 504 has 140～179 pitch angle of spending with described first loading surface 502, if chip 507 to be analyzed does not have vertical stratifications such as contact plunger or connection plug, with on described 507 first loading surface 502 that places level, it is done fractograph analysis.If have vertical stratifications such as contact plunger or connection plug in the chip 505 to be analyzed, described chip 505 is positioned on described second loading surface 504, because second loading surface 504 has 140 to 179 angles of cut of spending with first loading surface 502 of level, thereby the surface of described chip 505 and surface level have the angle of cut with described first loading surface 502 and 504 complementations of second loading surface, desire in described chip 505, to generate section, focused ion beam is moved to directly over the described chip 505 the beating of high energy and high speed focused particle beam to chip 505 surfaces.Described ion beam and described chip 505 surface normals form the angle with first loading surface 502 and 504 angle of cut complementations of second loading surface, as seen, the supplementary angle at the pitch angle of described second loading surface 504 and first loading surface 502 is the angle that described focused ion beam departs from the sample surfaces normal, by forming second loading surface 504 of differing tilt angles on the objective table, and the section that will described second loading surface 504 with differing tilt angles be applied to chip sample prepares the section surface that just can obtain different angles.Because the direction of the direction of ion beam and contact plunger or connection plug has the inclination of certain angle when making sample section with focused ion beam.Thereby thereby described ion beam can not cause damage can not influence the device layer of chip internal to the bottom of contact plug or attachment plug.Behind focused ion beam formation section surface, can carry out imaging to described section with scanning electron microscope and observe.
Figure 11 is the front elevation according to the sample bench of second embodiment of the invention; Figure 12 is that sample bench shown in Figure 11 is along the AA1 diagrammatic cross-section; Figure 13 is that sample bench shown in Figure 11 is along the BB1 diagrammatic cross-section;
As shown in figure 11, the objective table 500 of described sample bench comprises first loading surface 502, second loading surface 504, the 3rd loading surface 508 and the 4th loading surface 510, described first loading surface 502 and second loading surface 504 are arc, described the 4th loading surface 510 can with first loading surface, 502 coplanes, on described the 3rd loading surface 508, be formed with groove 512, on described the 4th loading surface, be formed with groove 514.
As shown in figure 12, described sample bench also comprises support bar 501, described first loading surface 502 and the 4th loading surface 510 coplanes, described first loading surface 502 and second loading surface, 504 angles of cut 503 are 140 to 179 degree, are formed with groove 514 on described the 4th loading surface 510.Described first loading surface 502 and second loading surface 504 are arc.Described support bar 501 is fixed in described objective table 500 back sides.
As shown in figure 13, described sample bench has objective table 500 and support bar 501, described the 3rd loading surface 508 and the 4th loading surface 510 angle of cut 503a are 140 to 179 degree, described the 3rd loading surface 508 has groove 512, described the 4th loading surface 510 has groove 514, and its corresponding loading surface in described groove 512,514 bottom surfaces is parallel.
As shown in figure 14, the said sample platform is applied to the focused ion beam fractograph analysis.At first, the support bar 501 of described sample bench is fixed in the section analysis equipment of focused ion beam, described first loading surface 502 is placed in horizontal direction, described second loading surface 504, described the 3rd loading surface 508 have 140 to 179 pitch angle of spending with described first loading surface 502, when if chip 507 to be analyzed does not have vertical stratification such as contact plunger or connection plug, described chip 507 is placed on first loading surface 502 of level, it is done fractograph analysis.If have vertical stratifications such as contact plunger or connection plug in the chip 505 to be analyzed, described chip 505 is positioned on described second loading surface 504, carry out fractograph analysis according to the described method of first embodiment.Described first loading surface 502 and second loading surface 504 are mainly used in chip lain against on the corresponding loading surface sample are carried out vertical section preparation, because present embodiment also has the 4th loading surface 510 of level and the 3rd loading surface 508 that tilts, described the 3rd loading surface 508 and the 4th loading surface 510 have groove 512 and 514 respectively, chip can be vertically placed on to carry out horizontal section preparation among the described groove.As shown in figure 14, chip 509 1 ends are vertically placed among the described groove 514, thereby can walk crosswise fractograph analysis to it, the sample bench in the embodiment of the invention also has the groove 512 that the bottom surface tilts, to satisfy the needs of differing tilt angles.
Figure 15 is the front elevation according to the sample bench of third embodiment of the invention; Figure 16 is that sample bench shown in Figure 15 is along the AA1 diagrammatic cross-section; Figure 17 is that sample bench shown in Figure 15 is along the BB1 diagrammatic cross-section.
As shown in figure 15, the objective table 500 of described sample bench comprises first loading surface 502, second loading surface 504, the 3rd loading surface 508 and the 4th loading surface 510, described first loading surface 502 and second loading surface 504 are arc, described the 4th loading surface 510 can with first loading surface, 502 coplanes, on described the 3rd loading surface and the 4th loading surface, be formed with clamping plate 511.
As shown in figure 16, described sample bench also comprises support bar 501, described first loading surface 502 and the 4th loading surface 510 coplanes, described first loading surface 502 and second loading surface, 504 angles of cut 503 are 140 to 179 degree, on described the 4th loading surface 510, be formed with clamping plate 511, described clamping plate have screw, have the groove that forms between 513, two clamping plate of nut in the described screw and can be used for vertical fixed chip.Described first loading surface 502 and second loading surface 504 are arc.Described support bar 501 is fixed in described objective table 500 back sides.
As shown in figure 17, described sample bench has objective table 500 and support bar 501, described the 3rd loading surface 508 and the 4th loading surface 510 angle of cut 503a are 140 to 179 degree, described the 3rd loading surface 508 and the 4th loading surface 510 have clamping plate 511, described clamping plate 511 have screw, and nut 513 is arranged in described screw.
Above-mentioned sample bench with a plurality of inclination loading surfaces and clamping plate is applied to the focused ion beam fractograph analysis.At first, the support bar 501 of described sample bench is fixed in the section analysis equipment of focused ion beam, described first loading surface 502 is placed in horizontal direction, described second loading surface 504, described the 3rd loading surface 508 have 140 to 179 pitch angle of spending with described first loading surface 502, when if chip to be analyzed does not have vertical stratification such as contact plunger or connection plug, described chip is placed on first loading surface 502 of level, it is done fractograph analysis.If have vertical stratifications such as contact plunger or connection plug in the chip to be analyzed, described chip is positioned on described second loading surface 504, carry out fractograph analysis according to the described method of first embodiment.Described first loading surface 502 and second loading surface 504 are mainly used in chip lain against on the corresponding loading surface sample are carried out vertical section preparation, because present embodiment also has the 4th loading surface 510 of level and the 3rd loading surface 508 that tilts, described the 3rd loading surface 508 and the 4th loading surface 510 have clamping plate 511 respectively, chip can be vertically placed on to carry out horizontal section preparation between the described clamping plate among the groove.
As shown in figure 18, use inclined surface of the present invention to have vertical stratification for example the chip 600 of contact plunger or connection plug 602 carry out section when preparing, after chip is positioned over the inclined surface of sample bench of the present invention, the surface normal of focused ion beam and chip of the present invention has pitch angle 606, thereby ion beam can not cause damage to other structure in the chip, has improved specimen preparation and has observed the accuracy that detects.Figure 19 can see at attachment plug and contact plug bottom not forming the slit defective from photo for using the sample section SEM photo that has attachment plug or contact plug of focused ion beam in sample bench preparation of the present invention.
Though the present invention with preferred embodiment openly as above; but it is not to be used for limiting the present invention; any those skilled in the art without departing from the spirit and scope of the present invention; can make possible change and modification, so protection scope of the present invention should be as the criterion with the scope that claim of the present invention was defined.
Claims (11)
1. sample bench, be applied to the focused ion beam fractograph analysis, comprise support bar and objective table, described objective table comprises first loading surface that is connected with described support bar, it is characterized in that: described objective table also comprises second loading surface that intersects with described first loading surface at least.
2. sample bench as claimed in claim 1 is characterized in that: described first loading surface and second loading surface are the plane, and the angle of cut is 140 to 179 degree.
3. sample bench as claimed in claim 1 is characterized in that: described objective table is projected as circle or ellipse along described support bar direction.
4. sample bench as claimed in claim 1 is characterized in that: described objective table is along the polygon that is projected as of described support bar.
5. sample bench as claimed in claim 1 or 2 is characterized in that: described first loading surface and second loading surface are the plane semicircle.
6. sample bench as claimed in claim 1 or 2 is characterized in that: described first loading surface and second loading surface are arc.
7. a sample bench is applied to the focused ion beam fractograph analysis, comprises support bar and objective table, and described objective table comprises first loading surface that is connected with described support bar, it is characterized in that:
Described objective table also comprises second loading surface and the 3rd loading surface that intersects with described first loading surface at least;
On described first loading surface and/or the 3rd loading surface, be formed with groove.
8. sample bench as claimed in claim 7 is characterized in that: the corresponding loading surface with it in the bottom surface of described groove is parallel.
9. sample bench as claimed in claim 7 is characterized in that: the angle of cut of described second loading surface, the 3rd loading surface and described first loading surface is 140 to 179 degree.
10. a sample bench is applied to the focused ion beam fractograph analysis, comprises support bar and objective table, and described objective table comprises first loading surface that is connected with described support bar, it is characterized in that:
Described objective table also comprises second loading surface and the 3rd loading surface that intersects with described first loading surface at least;
On described first loading surface and/or the 3rd loading surface, be formed with clamping plate.
11. sample bench as claimed in claim 10 is characterized in that: described clamping plate have screw, have screw in described screw.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNA2006101169046A CN101153855A (en) | 2006-09-30 | 2006-09-30 | Sample bench |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNA2006101169046A CN101153855A (en) | 2006-09-30 | 2006-09-30 | Sample bench |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN101153855A true CN101153855A (en) | 2008-04-02 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNA2006101169046A Pending CN101153855A (en) | 2006-09-30 | 2006-09-30 | Sample bench |
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| CN (1) | CN101153855A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104685348A (en) * | 2012-10-05 | 2015-06-03 | Fei公司 | High aspect ratio structure analysis |
| CN106629587A (en) * | 2016-10-25 | 2017-05-10 | 西安交通大学 | One-step molding method based on FIB (Focused Ion Beam) for large-angle normal-triple-prism-shaped pressure head |
-
2006
- 2006-09-30 CN CNA2006101169046A patent/CN101153855A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104685348A (en) * | 2012-10-05 | 2015-06-03 | Fei公司 | High aspect ratio structure analysis |
| JP2015533215A (en) * | 2012-10-05 | 2015-11-19 | エフ・イ−・アイ・カンパニー | Analysis of high aspect ratio structures |
| US9741536B2 (en) | 2012-10-05 | 2017-08-22 | Fei Company | High aspect ratio structure analysis |
| CN104685348B (en) * | 2012-10-05 | 2017-12-12 | Fei 公司 | High-aspect-ratio structure is analyzed |
| CN106629587A (en) * | 2016-10-25 | 2017-05-10 | 西安交通大学 | One-step molding method based on FIB (Focused Ion Beam) for large-angle normal-triple-prism-shaped pressure head |
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Open date: 20080402 |