US4277679A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus and method for contact-free potential measurements of an electronic composition
Assignee: Advantest Corp
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Filing: 1979-12-21
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Granted: 1981-07-07
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Expires: 1999-12-21
Abstract
Abstract A method and apparatus for the contact-free potential measurement at an electronic component using an electron beam wherein a predetermined potential is applied to the measuring point and the output voltage of a controlled gain amplifier is set to a predetermined reference value U S by means of controlling a photomultiplier voltage U PM and the photomultiplier voltage U PM is maintained constant. The measuring voltage U M is then determined from the difference of the voltages U R -U S between the control unit output voltage U R and the index value voltage U S . The method and apparatus allow the quantitative potential measurement to be made on the conducting paths of an integrated circuit without utilizing manual adjustments.
Inventors
- 👤 Hans P. Feuerbaum
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:46
CPC Classifications
H; H01; H01J; H01J49/00; H01J49/44; H01J49/46; H01J49/48; H01J49/488; G; G01; G01R; G01R31/00; G01R31/28; G01R31/302; G01R31/305; H01J37/00; H01J37/26; H01J37/266
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
140 words
A method for contact-free potential measurement of an electronic component with an electron microscope by means of measuring the energy of the secondary electrons with a spectrometer having a compensating circuit with a controlled-gain amplifier and to which a photomultiplier is connected, comprising the steps of connecting the measuring point of the component (12) to a pre-determined potential; and setting the output voltage (U R1 ) of the controlled-gain amplifier (38) to a pre-determined index value (U S ) with the control of the photomultiplier voltage (U PM ); and holding the photomultiplier voltage (U PM ) constant and, subsequently applying an operating voltage to the component (12) and determining the measured voltage (U m ) from the difference (U R -U S ) between the control unit output voltage (U R ) and the index value (U S ).
Claim 2
Independent Claim
140 words
A method for contact-free potential measurement of an electronic component with an electron microscope by means of measuring the energy of the secondary electrons with a spectrometer having a compensating circuit with a controlled-gain amplifier and to which a photomultiplier is connected, comprising the steps of connecting the measuring point of the component (12) to a pre-determined potential; and setting the output voltage (U R1 ) of the controlled-gain amplifier (38) to a pre-determined index value (U S ) with the control of the photomultiplier voltage (U PM ); and holding the photomultiplier voltage (U PM ) constant and, subsequently applying an operating voltage to the component (12) and determining the measured voltage (U m ) from the difference (U R -U S ) between the control unit output voltage (U R ) and the index value (U S ).
Claim 3
Dependent Claim
25 words
A method according to claim 1, characterized in that the measuring point of the component (12) is connected to zero potential during the first step.
Claim 4
Dependent Claim
119 words
Apparatus for contact-free measurement of an electronic component with an electron microscope and measuring the energy of secondary electrons with a scintillator comprising, means for connecting a pre-determined potential to said component (12); a controlled gain amplifier (38) connected to the photomultiplier (32) of said scintillator (26), a differential amplifier (46) connected to said amplifier (38) and its output supplies the measuring voltage (U m ), a comparator (50) which can be switched to receive an input from said amplifier (38) and has a second input comprising an index value voltage (U S ) and the output of said comparator (50) connected to control the photomultiplier voltage (U PM ) of the photomultiplier (32) through a control device (56).
Claim 5
Dependent Claim
119 words
Apparatus for contact-free measurement of an electronic component with an electron microscope and measuring the energy of secondary electrons with a scintillator comprising, means for connecting a pre-determined potential to said component (12); a controlled gain amplifier (38) connected to the photomultiplier (32) of said scintillator (26), a differential amplifier (46) connected to said amplifier (38) and its output supplies the measuring voltage (U m ), a comparator (50) which can be switched to receive an input from said amplifier (38) and has a second input comprising an index value voltage (U S ) and the output of said comparator (50) connected to control the photomultiplier voltage (U PM ) of the photomultiplier (32) through a control device (56).
Claim 6
Dependent Claim
150 words
Apparatus for contact-free potential measurements of a test sample comprising, an electron microscope mounted to irridate said test sample with an electron beam to produce secondary electron emission, a voltage control unit, a first switch connected to said test sample to connect it to said control voltage unit or a first reference fixed potential, a scintillator mounted to receive said secondary electron emission, a retarding field electrode mounted between said test sample and said scintillator, a photomultiplier tube connected to said scintillator, a controlled-gain amplifier connected to said photomultiplier tube and supplying an input to said retarding field electrode, a differential amplifier receiving the output of said controlled-gain amplifier, a second switch connected to said controlled gain amplifier, a comparator connected to said second switch, a second reference potential connected to said differential amplifier and to said comparator, and the output of said comparator connected to control said photomultiplier tube.
Claim 7
Dependent Claim
150 words
Apparatus for contact-free potential measurements of a test sample comprising, an electron microscope mounted to irridate said test sample with an electron beam to produce secondary electron emission, a voltage control unit, a first switch connected to said test sample to connect it to said control voltage unit or a first reference fixed potential, a scintillator mounted to receive said secondary electron emission, a retarding field electrode mounted between said test sample and said scintillator, a photomultiplier tube connected to said scintillator, a controlled-gain amplifier connected to said photomultiplier tube and supplying an input to said retarding field electrode, a differential amplifier receiving the output of said controlled-gain amplifier, a second switch connected to said controlled gain amplifier, a comparator connected to said second switch, a second reference potential connected to said differential amplifier and to said comparator, and the output of said comparator connected to control said photomultiplier tube.
Claim 8
Dependent Claim
13 words
Apparatus according to claim 4 wherein said first reference fixed potential is ground.
Claim 9
Dependent Claim
17 words
Apparatus according to claim 4 including an oscilloscope connected to the output of said controlled gain amplifier.
Claim 10
Dependent Claim
19 words
Apparatus according to claim 4 wherein a photomultiplier control unit is connected between said comparator and said photomultiplier tube.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-07-06 | 1985-01-05 | 1985-07-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-07-06 | 1989-01-05 | 1989-07-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-07-06 | 1993-01-05 | 1993-07-07 | $7700.00 | Window Closed / Lapsed |