US5424541A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Scanning electron microscope and method for controlling a scanning electron microscope
Assignee: Hitachi Ltd
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Filing: 1994-09-26
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Granted: 1995-06-13
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Expires: 2014-09-26
Abstract
Abstract A scanning electron microscope is provided with a channel cylinder between a sample and an electron source. The channel cylinder generates a deceleration electrical field to decelerate an electron beam emitted from the electron source. The channel cylinder has a portion having an electron source side and sample side. A detector is provided on the electron source side and sample channel cylinder portion. The detector detects the secondary signal emitted from the sample, so that a scan image is obtained with a high spatial resolution.
Inventors
- 👤 Hideo Todokoro
- 👤 Tadashi Ohtaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 10:12
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/26; H01J37/28; H01J2237/00; H01J2237/004; H01J2237/02; H01J2237/026; H01J2237/0268; H01J2237/04; H01J2237/047; H01J2237/0475; H01J2237/04756; H01J2237/244; H01J2237/24435; H01J2237/2448
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
98 words
A scanning electron microscope for scanning an electron beam on a grounded sample comprising: a condenser lens, an objective lens, a sample holder for holding a sample, an electron source for emitting said electron beam in a direction through the condenser lens and objective lens to a sample on the sample holder, a channel cylinder to which is applied positive voltage, said channel cylinder extending continuously from the condenser lens to the objective lens, and a detector for detecting said secondary signal, said detector being located along said channel cylinder intermediate the condenser lens and the sample holder.
Claim 2
Dependent Claim
98 words
A scanning electron microscope for scanning an electron beam on a grounded sample comprising: a condenser lens, an objective lens, a sample holder for holding a sample, an electron source for emitting said electron beam in a direction through the condenser lens and objective lens to a sample on the sample holder, a channel cylinder to which is applied positive voltage, said channel cylinder extending continuously from the condenser lens to the objective lens, and a detector for detecting said secondary signal, said detector being located along said channel cylinder intermediate the condenser lens and the sample holder.
Claim 3
Dependent Claim
29 words
A scanning electron microscope according to claim 1, wherein said sample is controlled such that the voltage of the sample is lower than the voltage of said channel cylinder.
Claim 4
Dependent Claim
17 words
A scanning electron microscope according to claim 2, wherein said electron source is a field-emission-type electron gun.
Claim 5
Dependent Claim
17 words
A scanning electron microscope according to claim 1, wherein said electron source is a field-emission-type electron gun.
Claim 6
Dependent Claim
20 words
A scanning electron microscope according to claim 1, wherein said detector has an attracting electrode for attracting said electron beam.
Claim 7
Dependent Claim
31 words
A scanning electron microscope according to claim 1, comprising a deceleration electric field former that forms a deceleration electric field for the electron beam between the objective lens and the sample.
Claim 8
Dependent Claim
47 words
A scanning electron microscope according to claim 6, wherein an opening for drawing attracted secondary signals to the outside of the channel cylinder is formed in the side of the channel cylinder and the secondary signal detector for taking secondary signals out of the opening for detection.
Claim 9
Dependent Claim
27 words
A scanning electron microscope according to claim 7, wherein an attracting electrode to which a potential for attracting secondary signals is provided is mounted in said opening.
Claim 10
Dependent Claim
33 words
A scanning electron microscope according to claim 6, wherein the secondary signal detector is a channel plate detector provided with an opening serving as an electron channel at a center of the opening.
Claim 11
Dependent Claim
20 words
A scanning electron microscope according to claim 9, further comprising means for applying a voltage to the channel plate detector.
Claim 12
Dependent Claim
17 words
A scanning electron microscope according to claim 6, wherein the secondary signal detector is a single-crystal scintillator.
Claim 13
Dependent Claim
38 words
A scanning electron microscope according to claim 6, further comprising potential barrier generating means for generating a potential barrier to sort secondary signals, the potential barrier generating means being arranged between the sample and the secondary signal detector.
Claim 14
Dependent Claim
46 words
A scanning electron microscope according to claim 6, further comprising a control electrode that generates an electric field to decrease the influence of the acceleration electric field generated by the channel cylinder on the sample, said control electrode being between the sample and the objective lens.
Claim 15
Dependent Claim
28 words
A scanning electron microscope according to claim 6, wherein the channel cylinder is an insulating cylinder with insulated conductive thin films coated on its inner and outer surfaces.
Claim 16
Dependent Claim
50 words
A scanning electron microscope according to claim 6, wherein the scanning electron microscope further comprises means for generating a magnetic field such that deflection of the primary electron beam due to the attracting electric field is canceled and the deflection of the secondary signal generated by the sample is supplemented.
Claim 17
Dependent Claim
28 words
A scanning electron microscope according to claim 6, further comprising an opening aperture in the channel cylinder which opening aperture has the same potential as the channel cylinder.
Claim 18
Dependent Claim
23 words
A scanning electron microscope according to claim 6, wherein the opening aperture has a different potential than the channel cylinder prior to mounting.
Claim 19
Independent Claim
93 words
A method of scanning an electron beam on a grounded sample, and obtaining an image on the basis of a secondary signal produced from said sample, comprising the steps of: scanning said electron beam onto said sample by passing said electron beam from an electron source through a condenser lens, an objective lens, and a channel cylinder extending continuously from the condenser lens to the objective lens; applying positive voltage to the channel cylinder; and detecting said secondary signal at a section of said channel cylinder intermediate the condenser lens and the sample.
Claim 20
Independent Claim
93 words
A method of scanning an electron beam on a grounded sample, and obtaining an image on the basis of a secondary signal produced from said sample, comprising the steps of: scanning said electron beam onto said sample by passing said electron beam from an electron source through a condenser lens, an objective lens, and a channel cylinder extending continuously from the condenser lens to the objective lens; applying positive voltage to the channel cylinder; and detecting said secondary signal at a section of said channel cylinder intermediate the condenser lens and the sample.
Claim 21
Dependent Claim
24 words
A method according to claim 18, further comprising controlling the voltage of the sample to be lower than the voltage of the channel cylinder.
Claim 22
Dependent Claim
15 words
A method according to claim 18, wherein said electron source is a field-emission-type electron gun.
Claim 23
Dependent Claim
18 words
A method according to claim 18, wherein said detector has an attracting electrode for attracting said electron beam.
Claim 24
Dependent Claim
24 words
A method according to claim 18, further comprising forming a deceleration electric field for the electron beam between the objective lens and the sample.
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