CN1888881A - Method for charged contrast imaging - Google Patents
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- CN1888881A CN1888881A CNA2006100889923A CN200610088992A CN1888881A CN 1888881 A CN1888881 A CN 1888881A CN A2006100889923 A CNA2006100889923 A CN A2006100889923A CN 200610088992 A CN200610088992 A CN 200610088992A CN 1888881 A CN1888881 A CN 1888881A
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Abstract
A charged contrast image method of scan electron microscope applies in the microanalysis analysis technology. It adopts scan electron microscope with high vacuum, puts on insulated sample with accelerated pressure 10-30kV, puts on complex grain which made by conductor and non-conductor stuff and multi layer film with accelerated pressure 25-30kV, and with 10-10-10-11A incidence current, 6-80s/frame scan velocity. When the vacuum arrives to 1*10-4Pa or more than it, it scans the sample surface with incidence electron and keeps the secondary electron microscopy. When the circumstance scan electron microscope is working, the imaging operation condition is same with the scan electron microscope with high vacuum, and the press of the sample room is lower than the press of accustomed charged compensate, so the insulated material is 13-90Pa, moisture and critter material is 400-500Pa. It uses for observing the difference of conductive, piezoelectric and stress capability and the character about microstructure and component distributing.
Description
Technical field
The present invention relates to a kind ofly in scanning electron microscope, utilize electric charging effect that non-conductive sample produces under electron beam irradiation to form the method for charged contrast picture.Be applied in the Electronic Micro-Analysis technology.
Background technology
When adopting scanning electron microscope (SEM) to observe with imaging to non-conductive sample, the incident electron of irradiation on non-conductive sample can not pass through sample ground connection, produces charging and electric discharge phenomena in the nonconductor but be deposited in, and promptly produces electric charging effect.Electric charging effect makes that distortion appears in secondary electron image, sweep trace is discontinuous or produces phenomenon such as anomaly contrast, has had a strong impact on the quality of image.Therefore non-conductive samples such as pottery, macromolecule, moisture biomaterial can not directly be observed in the high vacuum scanning electron microscope.How reducing and eliminate the electric charging effect that non-conductive sample produces is the problem that needs emphasis to solve in the scanning electron microscopy analysis.
Traditional method that reduces and eliminate electric charging effect is at non-conductive sample surface evaporation one deck conducting coating, as metal films such as gold, silver, platinum, or carbon film, to improve the electrical conductance on non-conductive sample surface.But conducting film can be covered the real topography details of sample surfaces, and has reduced some more weak physics image contrasts, as composition contrast, crystalline orientation contrast, voltage contrast and magnetic contrast etc.
Advanced at present technology is to adopt low-voltage scanning electron microscope (LV-SEM), transformation power scanning electron microscope (VP-SEM) and environmental scanning electronic microscope (ESEM), and making non-conductive sample needn't plate conducting film just can Direct observation.LV-SEM is by reducing the incident electron beam energy, reduce the irradiation damage and the electric charge accumulation of sample surfaces, reducing electric charging effect with this.The principle of VP-SEM and ESEM complement of chargeability is: feed water vapour, atmosphere or other gas in the sample chamber, gas molecule with the collision process of incident electron and signal electron (secondary electron, backscattered electron) in be ionized, produce positive ion go in and the negative charge that accumulates in the non-conductive sample, eliminate electric charging effect.
In SEM, the high-energy electron irradiation sample, from sample, excite signals such as producing secondary electron, backscattered electron, absorption electronics, characteristic X-ray, cathode-luminescence, form pattern contrast picture, composition contrast and crystalline orientation contrast picture, X-ray picture, cathode-luminescence picture, voltage contrast picture, magnetic contrast picture, and electron beam induced current/voltage picture etc.These contrast features include information such as the surface topography of sample and structure, chemical constitution, crystalline orientation, electrical voltage/current profile, magnetic domain, and these contrast mechanism have been familiar with by people, and are used widely in the micro-analysis of material.
Present above-mentioned advanced person's complement of chargeability technology all is to be conceived to how to reduce and eliminate the electric charging effect that non-conductive sample produces under electron beam irradiation, therefore also obtain because material there are differences at aspect of performances such as conduction, dielectric, stress, form that local is caught energy of a charge difference and the figure image contrast that demonstrates.
Summary of the invention
The objective of the invention is the electric charging effect that utilizes non-conductive sample under electron beam irradiation, to produce, propose a kind of method of charged contrast imaging.Utilize the charged contrast picture, observing the existing complement of chargeability technology of employing institute can't be observed, the difference that the sample local exists at aspect of performances such as conduction, dielectric, stress, and the feature of micromechanism and component distributing.
The present invention is based on non-conductive sample is carried out in the process of complement of chargeability, the applicant finds under some specific image-forming conditions of charged undercompensation, in the secondary electron image of non-conductive sample, a kind of special figure image contrast can appear, it is to catch electric charge and a kind of image contrast of forming by the nonconductor part, i.e. charged contrast.Charged contrast is easily at the defective locations of non-conductive sample, form in the zone that performances such as composition fluctuating and electrical conductance, dielectricity, strain there are differences.Therefore the present invention's electric charging effect of utilizing non-conductive sample to produce in SEM is selected suitable imaging operation condition and environmental baseline, forms the state of charged undercompensation, proposes the method for a kind of novel contrast picture of acquisition.In the high vacuum scanning electron microscope,, form the charged contrast picture by regulating the irradiation dose of incident electron; In VP-SEM and ESEM,, form the charged contrast picture by regulating the irradiation dose and the sample chamber pressure of incident electron.Utilize the charged contrast picture, performances such as research non-conductive sample local conduction, dielectric, strain, and features such as microstructure and defective, chemical constitution distribution.
The method of the charged contrast imaging that the present invention proposes realizes as follows:
1, under the situation that adopts the imaging of high vacuum scanning electron microscope
(1) selects imaging operation condition: comprise accelerating potential, incident current, sweep limit and sweep time.General insulated sample is selected accelerating potential scope (10kV-30kV) for use.Select high accelerating potential (25kV-30kV) for use by composite particles and multilayer film sample that conductor and non-conductive material constitute, the non-conductive district that incident electron can be penetrated in the sample arrives conduction region, reduces electric charging effect.The too high electric charging effect that makes of accelerating potential is serious, hangs down excessively electric charging effect is eliminated substantially, all is difficult to form good charged contrast.Incident current selects 10 for use
-10～10
-11A.Sweep speed is selected 6s/ frame～80s/ frame, sweep speed faster, 6s/ frame～30s/ frame, help forming tangible charged contrast, but too fast sweep speed, less than the 6s/ frame, figure image contrast and signal to noise ratio (S/N ratio) are descended, be unfavorable for forming tangible charged contrast.
(2) sample is put into the scanning electron microscope example chamber, made sample and sample stage good earth, vacuumize then.When the sample vacuum chamber degree reaches 1 * 10
-4Pa or 1 * 10
-4When Pa is above, apply accelerating potential, produce incident electron and scan at sample surfaces to electron gun.Adopt scintillator-photomultiplier secondary electron probe (ETD) to receive secondary electron, and preserve secondary electron image.
2, under the situation that adopts environmental scanning electronic microscope (ESEM) imaging
(1) selects imaging operation condition, with high vacuum SEM.
(2) ambient pressure conditions of selection sample chamber.Pressure will be lower than the pressure that common complement of chargeability adopts.Insulating material such as pottery adopt the imaging of low vacuum environment, adopt 13Pa～90Pa; Moisture and biomaterial adopts the imaging of environment vacuum mode, adopts 400Pa～500Pa.Environmental pressure is low excessively to make electric charging effect serious, and the too high electric charging effect that makes is eliminated fully, all is difficult to form charged contrast.
(3) sample is put into ESEM, make sample and sample stage good earth.Vacuumize then.After the sample vacuum chamber degree reaches above-mentioned setting value, apply accelerating potential for the ESEM electron gun, produce incident electron and scan at sample surfaces.Adopt gas secondary electron probe (GSED) to receive secondary electron, and preserve secondary electron image.
The present invention proposes the method for charged contrast imaging, the formation principle of its charged contrast picture is:
Charged contrast is the potential well trapped electrons on non-conductive sample surface and nearly surface, is brought out a kind of special image contrast that forms in secondary electron image by electric charge.It is produced by local electric charging effect, and therefore, when charged phenomenon is eliminated fully, or charged phenomenon is very serious, and all can not form charged contrast through the sample of conductive processing.Its image-forming condition should satisfy the carrying capacity σ of unit interval implantation sample
0Damping capacity σ greater than implanting electric charge sees formula (1).σ
0Can promptly change incident current I by changing electron irradiation dosage
0, sweep speed F and enlargement ratio A control, and sees formula (2).Therefore adopt suitable imaging operation condition, just can reach charged unbalanced state.σ is relevant with the conductivity gamma and the DIELECTRIC CONSTANT of electron irradiation time t and sample irradiation zone, and τ=γ/ε is the time constant of charge decay, sees formula (3).If not there is defective in the conducting sample, comprise the defective that produces under intrinsic fault of construction or the external action, and there are differences such as conduction, dielectric, strain in the sample, will cause the sample local to catch the difference of electric charge ability and the difference of charged decay, under suitable image-forming condition, form charged contrast.
σ
0＞σ (1)
σ
0＝I
0(1-δ-η)F/A (2)
σ(t)＝σ
0e
-t/τ (3)
The image-forming condition that forms charged contrast in high vacuum scanning electron microscope (SEM) and environmental scanning electronic microscope (ESEM) is different.In high vacuum SEM, general sample vacuum chamber degree is better than 10
-3Pa (tungsten filament electron gun) or 10
-4Pa (field emission gun).The charge effect that reduces non-conductive sample is realized by selecting suitable imaging operation condition, promptly selects accelerating potential, incident current, sweep limit and sweep speed.Change incident current, sweep limit and sweep speed, promptly changed the residence time of electric charge in sample; Change accelerating potential, promptly changed the scattering degree of depth of electronics in sample and the accumulation degree of depth of electric charge.The spread R of electronics in different samples
MaxCan calculate atomic number, molecular weight and the density of Z, W and ρ difference representative sample in the formula according to formula (4); E
0Represent the incident electron energy.Also can obtain R by the MonteCarlo analogy method
Max
In ESEM, except selecting imaging operation condition, also need to select the gaseous tension in the sample chamber, make non-conductive sample remain on the state of charged undercompensation.According to the pressure-phase diagrams of water, can determine the complement of chargeability condition in the water vapor, see Fig. 1.Usually the condition setting that non-conductive sample is carried out complement of chargeability is near the water saturation vapour pressure, below the solid i.e. gas-liquid of water-transition curve, shown in the shadow region part among Fig. 1.For example between-5 ℃ and 30 ℃, the pressure operated by rotary motion is at 600Pa～800Pa.The pressure that forms the charged contrast imaging employing then needs to be lower than the pressure that complement of chargeability adopts, and adopts 400Pa～500Pa.
The electric charging effect that the present invention utilizes non-conductive sample to produce under electron beam irradiation, proposition forms the method for charged contrast picture.Therefore charged contrast similarly is to form under the condition of electric charging effect undercompensation, at higher incident electron energy, faster under sweep speed and the lower environmental pressure, form charged contrast easily.In the high vacuum scanning electron microscope, form charged contrast, need to regulate the irradiation dose of incident electron, comprise image-forming conditions such as accelerating potential, incident current, sweep speed, enlargement ratio; In transformation power and environmental scanning electronic microscope, form charged contrast, need to regulate the pressure of image-forming condition and sample chamber.The contrast picture that electric charging effect forms, be electric charging effect compensation back can not present.The information that charged contrast presents is other contrast that usually forms in scanning electron microscope, as pattern contrast, composition contrast, crystallography contrast, voltage contrast, information that magnetic contrast did not comprise, so can not be explained with other contrast mechanism.By research and explanation, can estimate in the non-conducting material (pottery, macromolecule, compound substance, biomaterial etc.) and performances such as the closely-related local conduction of microscopic appearance, fault of construction and component distributing, dielectric, strain the unique information that comprised in the charged contrast picture.
Description of drawings
Pressure-the phase diagrams of Fig. 1 water
Fig. 2 PbTiO
3Powder coats the secondary electron image of Ni particulate samples
(a) 5wt%PbTiO
3-Ni charged contrast picture (b) 10wt%PbTiO
3-Ni charged contrast picture
(c) 5wt%PbTiO
3-Ni time charge pattern
The secondary electron image of the micro-impression sample of feldspar porcelain under Figure 31 000gf load
(a) the sample vacuum chamber degree 1 * 10
-3Pa (b) sample vacuum chamber degree 90Pa
(c) sample vacuum chamber degree 800Pa
The secondary electron image of Fig. 4 hydrogel sample under sample vacuum chamber degree 600Pa and 400Pa
(a)600Pa (b)400Pa
The charged contrast picture of Fig. 5 sapphire etching step profile section sample
(a) enlargement ratio 50 * (b) enlargement ratios 3000 *
The secondary electron image of sapphire etching step profile section sample under the different accelerating potentials of Fig. 6
(a) accelerating potential 5kV (b) accelerating potential 20kV (c) accelerating potential 30kV
The charged contrast picture of sapphire etching step profile section sample under Fig. 7 different scanning rates
(a) 6s/ frame (b) 25s/ frame (c) 85s/ frame
The charged contrast picture of sapphire etching step profile section sample under Fig. 8 different pressures
(a)13Pa (b)40Pa (c)80Pa
Embodiment
Below in conjunction with concrete condition the method for charged contrast imaging of the present invention is described, and the validity of this method is described in conjunction with the experimental result that Fig. 2～Fig. 8 provides.
The experiment condition of the scanning electron microscope that adopts in the present embodiment is:
1, high vacuum scanning electron microscope: adopt the JEOL 6500F of company high-resolution thermal field emission scan Electronic Speculum (FE-SEM).The sample vacuum chamber degree is better than 1 * 10
-4Pa.Accelerating potential 5kV～30kV; Incident current 10
-8～10
-12A; Sweep speed 0.1s/ frame～100s/ frame.Detector is scintillator-photomultiplier secondary electron probe (ETD).2, environmental scanning electronic microscope: adopt the Quanta of FEI Co. 200 type environmental scanning electronic microscopes (ESEM).High vacuum 1 * 10
-3Pa～5 * 10
-4Pa; Low vacuum 13Pa～130Pa; Environment vacuum 133Pa～2600Pa.Accelerating potential 5kV～30kV; Incident current 10
-8～10
-12A; Sweep speed 0.1s/ frame～100s/ frame.The high vacuum pattern adopts the ETD probe; Low vacuum and environment vacuum mode adopt gas secondary electron probe (GSED).
Embodiment 1: the charged contrast imaging method of composite particles, and step is as follows:
(1) adopts FE-SEM, select accelerating potential 30kV, incident current 10
-11A, enlargement ratio are * 50000, and sweep speed is the image-forming condition of 80s/ frame.
(2) composite particles is put into FE-SEM, make sample and sample stage good earth, vacuumize then.When the sample vacuum chamber degree reaches 1 * 10
-4During Pa, apply accelerating potential, produce incident electron and scan at sample surfaces to electron gun.Adopt the ETD probe to receive secondary electron, and preserve secondary electron image.
Fig. 2 (a) and (b) be PbTiO
3Nano powder coats the secondary electron image of the composite particles sample of Ni particle.Composite particles is of a size of the hundreds of nanometer.When not plating conducting film, clearly demonstrate the composite particles surface in the secondary electron image by one deck PbTiO
3Halo coats, and the width of halo is with PbTiO
3The increase of additional proportion and increasing, this is because PbTiO
3There is notable difference with Ni in conductance, makes electric charge accumulation at PbTiO
3Formed charged contrast in the layer.High-energy tail by measured X-ray bremstrahlen can calculate, at PbTiO
3The two-phase interface place of/Ni composite particles has formed one about 10
3～10
4The electric field of V/cm.This highfield has suppressed some pattern details of sample surfaces, and has given prominence to the difference that sample exists on electrical conductance and chemical analysis.Because PbTiO
3The about 0.1 μ m of the thickness of halo layer, and energy is that the incident electron of 30keV is at PbTiO
3In penetration depth be about 5～6 μ m, incident electron has passed the Ni particle that non-conductive layer enters into conduction, thereby has reduced electric charging effect, has obtained charged contrast picture clearly.The composite particles that the surface is coated with the Pt film does not then demonstrate charged contrast, sees Fig. 2 (c).
Embodiment 2: the charged contrast imaging method of the micro-impression of feldspar porcelain, and step is as follows:
(1) adopts ESEM, select accelerating potential 30kV, incident current 10
-10A, enlargement ratio * 1600, the image-forming condition of sweep speed 30s/ frame.Sample chamber pressure is respectively 1 * 10
-3Pa, 90Pa and 800Pa.
(2) the feldspar porcelain sample is put into ESEM, make sample and sample stage good earth, vacuumize.When the sample vacuum chamber degree reaches (a) 1 * 10
-3During Pa, apply accelerating potential, produce incident electron and scan, adopt the ETD probe to receive secondary electron, and preserve secondary electron image at sample surfaces to electron gun.When the sample vacuum chamber degree reaches (b) 90Pa and (c) during 800Pa, applies accelerating potential to electron gun, produce incident electron and scan at sample surfaces, adopt the GSED probe to receive secondary electron, and preserve secondary electron image.
Fig. 3 (a) is 1 * 10
-3Imaging under the Pa, serious electric charging effect appears in feldspar porcelain impression sample surfaces, makes pattern distortion, is difficult to observe the real topography of impression.Fig. 3 (b) imaging under 90Pa, electronics is hunted down in the defective locations of sample and plastic strain district and has formed charged contrast.Fig. 3 (c) imaging under 800Pa, the complete obiteration of charged phenomenon, but can not form charged contrast.
Embodiment 3: the charged contrast imaging method of environmental sensitive hydrogels sample, and step is as follows:
(1) adopts ESEM, select accelerating potential 10kV (Fig. 4 (a)) and 12.5kV (Fig. 4 (b)), incident current 10
-10A, enlargement ratio * 3000, the image-forming condition of sweep speed 30s/ frame.Sample chamber pressure is respectively (a) 600Pa and (b) 400Pa.
(2) the environmental sensitive hydrogels sample is put into ESEM, make sample and sample stage good earth, vacuumize.When the sample vacuum chamber degree reaches 600Pa and 400Pa, apply accelerating potential to electron gun, produce incident electron and scan at sample surfaces, adopt the GSED probe to receive secondary electron, and preserve secondary electron image.
600Pa near water saturation vapour pressure condition under imaging, electric charging effect is eliminated fully, but the secondary electron image contrast is low, also fails to form charged contrast, sees Fig. 4 (a).In the 400Pa imaging, electric charging effect is eliminated as yet fully, but clearly demonstrates several microns to tens microns porous structure and chain feature of hydrogel in the secondary electron image, sees Fig. 4 (b).
Embodiment 4: the charged contrast imaging method of sapphire samples
When adopting FE-SEM, the step of charged contrast imaging is as follows:
(1) selects imaging operation condition: accelerating potential, incident current, sweep limit and sweep time.
(2) the sapphire samples sample is put into FE-SEM, make sample and sample stage good earth, vacuumize.When the sample vacuum chamber degree reaches 9 * 10
-5During Pa, apply accelerating potential, produce incident electron and scan at sample surfaces to electron gun.Adopt the ETD probe to receive secondary electron, and preserve secondary electron image.
The operating conditions that is chosen to picture below is described respectively with reference to the accompanying drawings:
Fig. 5 is among the FE-SEM, and imaging parameters is accelerating potential 30kV, incident current 10
-11A, sweep speed 25s/ frame, enlargement ratio 50 * (Fig. 5 (a)) and 3000 * (Fig. 5 (b)).Observe the charged contrast that forms in the cross-sectional sample of sapphire etching step.Demonstrate in secondary electron image at high 200nm, the lower surface of the etching step of long 200 μ m presents periodic evenly bright band, and bright band length is similar to length of bench.Owing to have step and no stepped area on the pattern in cross section and composition, all not have difference, this cycle bright band demonstrates stepped region and non-stepped region exists difference on the trapped electrons ability, reflect the ion implantation technology that the etching step is adopted, may make the lattice on sapphire surface and nearly surface produce distortion and local stress, show that charged contrast demonstrates the state of crystal local strain.
Fig. 6 is among the FE-SEM, the secondary electron image that different accelerating potentials obtain down, and other imaging parameters is identical with Fig. 5.When accelerating potential is 5kV, even bright band does not appear below sapphire etching step, promptly do not form charged contrast.When accelerating potential is increased to 10kV and 30kV, formed charged contrast, and charged bright band width increases along with the increase of accelerating potential.This is because under low accelerating potential, the electron trap of catching electric charge is many to be formed at sample surfaces, is difficult to form the state of charged accumulation; Along with the incident electron energy increases, the electronic action degree of depth increases, and the electron trap degree of depth also increases thereupon, charged being not easy that accumulates in the sample is dissipated, thereby present tangible charged contrast in secondary electron image.
Fig. 7 is among the FE-SEM, and different scanning rates is to the influence of charged contrast, and other imaging parameters is identical with Fig. 5.With the sweep speed of 6s/ frame and 25s/ frame, charged contrast is fairly obvious; When sweep speed is decreased to the 85s/ frame, resides in the charge decay in the sample and charged contrast is obviously weakened.
When adopting ESEM, the step of charged contrast imaging is as follows:
(1) select accelerating potential 30kV, enlargement ratio 300 *, incident current 10
-10A, sweep speed 30s/ frame, sample chamber pressure are respectively imaging under the condition of 10Pa, 40Pa and 80Pa.
(2) sample is put into ESEM, make sample and sample stage good earth, vacuumize.When the sample vacuum chamber degree reaches above-mentioned value, apply accelerating potential for the ESEM electron gun, produce incident electron and scan at sample surfaces.Adopt the GSED probe to receive secondary electron, and preserve secondary electron image.
Fig. 8 is in ESEM, the charged contrast that forms under different pressures.During imaging, charged contrast is very weak under pressure 13Pa.When pressure was increased to 40Pa and 80Pa, charged contrast was enhanced.
Claims (2)
1, the method for charged contrast imaging is characterized in that: realize as follows:
Under the situation that adopts the imaging of high vacuum scanning electron microscope:
1) selects imaging operation condition: comprise accelerating potential, incident current, sweep speed; It is 10kV～30kV that insulated sample is selected the scope of accelerating potential for use, and the scope of selecting accelerating potential for use by synthetic composite particles of conductor and non-conductive material and multilayer film sample is 25kV～30kV, and incident current selects 10 for use
-10～10
-11A, sweep speed is selected 6s/ frame～80s/ frame;
2) sample is put into the scanning electron microscope example chamber, made sample and sample stage good earth, vacuumize then; When the sample vacuum chamber degree reaches 1 * 10
-4Pa or 1 * 10
-4When Pa is above, apply accelerating potential, produce incident electron and scan, adopt scintillator-photomultiplier secondary electron probe to receive secondary electron, and preserve secondary electron image at sample surfaces to electron gun;
Under the situation that adopts the environmental scanning electronic microscope imaging:
1) selects imaging operation condition, with the high vacuum scanning electron microscope;
2) ambient pressure conditions of selection sample chamber; Pressure will be lower than the pressure that common complement of chargeability adopts, and insulating material adopts the low vacuum pattern, in the scope imaging of 13Pa～90Pa; Moisture and biomaterial adopts the environment vacuum mode, in the scope imaging of 400Pa～500Pa;
3) sample is put into environmental scanning electronic microscope, make sample and sample stage good earth, vacuumize then; After the sample vacuum chamber degree reaches above-mentioned setting value, apply accelerating potential for the ESEM electron gun, produce incident electron and scan at sample surfaces, adopt gas secondary electron probe to receive secondary electron, and preserve secondary electron image.
2, the method for charged contrast imaging according to claim 1 is characterized in that: under the situation that adopts high vacuum scanning electron microscope and environmental scanning electronic microscope imaging, adopt the sweep speed of 6s/ frame～30s/ frame in the step 1).
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103344789A (en) * | 2013-07-05 | 2013-10-09 | 北京工业大学 | Thin sample transmission filtration-reflection receiving type contrast separation imaging method in scanning electron microscope |
| CN103454296A (en) * | 2013-08-27 | 2013-12-18 | 同济大学 | Method for improving quality of energy spectrum face distribution image of inorganic non-metal material sample |
| CN112379129A (en) * | 2020-11-16 | 2021-02-19 | 付学文 | High-space-time resolution multi-mode carrier dynamics measurement system and measurement method |
| CN112461880A (en) * | 2020-11-05 | 2021-03-09 | 中国空间技术研究院 | Method for positioning and detecting surface conductive type passage of glass sealing structure |
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2006
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| CN103344789A (en) * | 2013-07-05 | 2013-10-09 | 北京工业大学 | Thin sample transmission filtration-reflection receiving type contrast separation imaging method in scanning electron microscope |
| CN103344789B (en) * | 2013-07-05 | 2015-09-09 | 北京工业大学 | Scanning electron microscope thin sample transmission filtration-reflection receivable formula contrast method for separate imaging |
| CN103454296A (en) * | 2013-08-27 | 2013-12-18 | 同济大学 | Method for improving quality of energy spectrum face distribution image of inorganic non-metal material sample |
| CN112461880A (en) * | 2020-11-05 | 2021-03-09 | 中国空间技术研究院 | Method for positioning and detecting surface conductive type passage of glass sealing structure |
| CN112379129A (en) * | 2020-11-16 | 2021-02-19 | 付学文 | High-space-time resolution multi-mode carrier dynamics measurement system and measurement method |
| CN112379129B (en) * | 2020-11-16 | 2022-08-23 | 付学文 | High-space-time-resolution multi-mode carrier dynamics measurement system and measurement method |
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