Patent US3890631A successfully refreshed from Google Patents.
US3890631A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable capacitance semiconductor devices
Assignee: General Electric Co
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Filing: 1973-12-26
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Granted: 1975-06-17
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Expires: 1993-12-26
Abstract
Abstract A high frequency CIS capacitance device having a substrate of one conductivity type provides a capacitance for a high frequency signal applied across a pair of capacitance electrodes thereof which is dependent on the voltages applied to a pair of control electrodes, each connected to the surface adjacent region of the substrate underlying one of the pair of capacitance electrodes of the device through a respective channel region of opposite conductivity type. Means are provided for alternatively establishing one or the other channel regions of opposite conductivity type to establish values of capacitances dependent on the voltages applied to the control electrodes. Composite devices are formed of elemental devices such as described in which the capacitance of the composite device is the sum of the capacitance of the elemental devices and is variable in discrete increments to provide a large number of discrete values of capacitance in response to digital signals applied to a minimum number of control electrodes connected thereto.
Inventors
- 👤 Jerome J Tiemann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:11
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/60; H10D1/62; H10D1/66
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
313 words
Semiconductor apparatus for providing a capacitance for a high frequency signal variable in discrete increments comprising a substrate of semiconductor material of one type conductivity including a plurality of spaced surface adjacent regions, a plurality of capacitance providing electrodes, each insulatingly overlying and spaced a predetermined distance from a respective surface adjacent region of said substrate and forming with respect to a common electrode connected to said substrate a respective capacitor, said capacitance providing electrodes being connected together to provide a common capacitance providing electrode of said apparatus, means for applying a depletion producing voltage between said common capacitance providing electrode and said common electrode corresponding to a predetermined surface potential having an absolUte value less than said depletion producing voltage but greater than the inversion threshold voltage of said apparatus, means for applying a high frequency signal between said common capacitance providing electrode and said common electrode control means for establishing individually in each of said surface adjacent regions a first potential in relation to said substrate corresponding to a respective low value of capacitance between a respective capacitance providing electrode and said common electrode, and for establishing alternatively and individually in each of said surface adjacent regions a second potential in relation to said substrate corresponding to a respective high value of capacitance between a respective capacitance providing electrode and said common electrode, whereby the capacitance of said device is variable in increments dependent on the particular potentials established in the surface adjacent regions of the capacitors from a minimum value corresponding to the sum of the low value capacitances of the capacitors when said first potential is established in all of the surface adjacent regions of said capacitors to a maximum value corresponding to the sum of the high value capacitances of the capacitors when said second potential is established in all of said surface adjacent regions of said capacitors.
Claim 2
Dependent Claim
313 words
Semiconductor apparatus for providing a capacitance for a high frequency signal variable in discrete increments comprising a substrate of semiconductor material of one type conductivity including a plurality of spaced surface adjacent regions, a plurality of capacitance providing electrodes, each insulatingly overlying and spaced a predetermined distance from a respective surface adjacent region of said substrate and forming with respect to a common electrode connected to said substrate a respective capacitor, said capacitance providing electrodes being connected together to provide a common capacitance providing electrode of said apparatus, means for applying a depletion producing voltage between said common capacitance providing electrode and said common electrode corresponding to a predetermined surface potential having an absolUte value less than said depletion producing voltage but greater than the inversion threshold voltage of said apparatus, means for applying a high frequency signal between said common capacitance providing electrode and said common electrode control means for establishing individually in each of said surface adjacent regions a first potential in relation to said substrate corresponding to a respective low value of capacitance between a respective capacitance providing electrode and said common electrode, and for establishing alternatively and individually in each of said surface adjacent regions a second potential in relation to said substrate corresponding to a respective high value of capacitance between a respective capacitance providing electrode and said common electrode, whereby the capacitance of said device is variable in increments dependent on the particular potentials established in the surface adjacent regions of the capacitors from a minimum value corresponding to the sum of the low value capacitances of the capacitors when said first potential is established in all of the surface adjacent regions of said capacitors to a maximum value corresponding to the sum of the high value capacitances of the capacitors when said second potential is established in all of said surface adjacent regions of said capacitors.
Claim 3
Dependent Claim
195 words
The combination of claim 1 in which said control means comprises a first control electrode and means for producing a plurality of first channel regions of opposite conductivity in said substrate each connected between said first control electrode and a respective surface adjacent region, the time constant of the capacitance of each of said surface adjacent regions and the resistance of the first channel connected thereto from said first electrode being large in relation to a period of said high frequency signal, a second control electrode and means for producing a plurality of second channel regions of opposite conductivity in said substrate, each connected between said second control electrode and a respective surface adjacent region, the time constant of the capacitance of each of said surface adjacent regions and the resistance of the second channel region connected thereto from said second electrode being large in relation to a period of said high frequency signal, means for providing said first potential to said first control electrode and for providing said second potential to said second control electrode, channel establishing means for individually and alternatively establishing the channel regions connected to each of said surface adjacent regions.
Claim 4
Dependent Claim
68 words
The combination of claim 2 in which said channel establishing means comprises a plurality of first gate electrodes, each spaced in insulated relationship to said substrate to provide a respective first channel region when energized, and a plurality of second gate electrodes, each spaced in insulated relationship to said substrate to provide a respective second channel region when energized, means for alternatively energizing each pair of gate electrodes.
Claim 5
Dependent Claim
49 words
The combination of claim 1 in which the areas of said capacitance providing electrodes are consecutively arranged according to size into a series, each area of the series starting with the second being set in relation to the preceding area of the series to provide twice the capacitance thereof.
Claim 6
Dependent Claim
240 words
Semiconductor apparatus for providing a plurality of discrete values of capacitance for a high frequency signal comprising a pair of semiconductor devices, each including a body of semiconductor material of one type conductivity having a major surface, a conductive member insulatingly overlying a first surface adjacent region of said body and constituting a first capacitance providing electrode of said device, conductive means in electrical contact with another region of said body and forming a second electrode of said device, the first capacitance providing electrodes of said devices bEing connected together and the second electrodes of said devices being connected together, means for applying a depletion producing voltage between said common capacitance providing electrodes and said common electrode corresponding to a predetermined surface potential having an absolute value less than said depletion producing voltage but greater than the inversion threshold voltage of said apparatus, means for applying a high frequency signal between said common capacitance providing electrode and said common electrode, means for establishing alternatively, in each of the surface-adjacent regions of said devices of different potentials corresponding to different values of capacitance between said first and second electrodes of a respective device, means for preselecting the combination of predetermined potentials simultaneously established in said surface adjacent regions, whereby discrete values of capacitance are obtained between said first and second electrodes of said devices each corresponding to a respective combination of potentials established in the surface adjacent regions of said devices.
Claim 7
Dependent Claim
240 words
Semiconductor apparatus for providing a plurality of discrete values of capacitance for a high frequency signal comprising a pair of semiconductor devices, each including a body of semiconductor material of one type conductivity having a major surface, a conductive member insulatingly overlying a first surface adjacent region of said body and constituting a first capacitance providing electrode of said device, conductive means in electrical contact with another region of said body and forming a second electrode of said device, the first capacitance providing electrodes of said devices bEing connected together and the second electrodes of said devices being connected together, means for applying a depletion producing voltage between said common capacitance providing electrodes and said common electrode corresponding to a predetermined surface potential having an absolute value less than said depletion producing voltage but greater than the inversion threshold voltage of said apparatus, means for applying a high frequency signal between said common capacitance providing electrode and said common electrode, means for establishing alternatively, in each of the surface-adjacent regions of said devices of different potentials corresponding to different values of capacitance between said first and second electrodes of a respective device, means for preselecting the combination of predetermined potentials simultaneously established in said surface adjacent regions, whereby discrete values of capacitance are obtained between said first and second electrodes of said devices each corresponding to a respective combination of potentials established in the surface adjacent regions of said devices.
Claim 8
Dependent Claim
37 words
The combination of claim 5 in which said devices include a common body of semiconductor material having a major surface and in which each of said first electrodes are spaced a predetermined distance from said major surface.
Claim 9
Dependent Claim
31 words
The combination of claim 6 in which the different potentials established in a surface adjacent region of a device are two in number and are identical for each of the devices.
Claim 10
Dependent Claim
28 words
The combination of claim 5 in which the area of the first electrode of one device is twice the area of the first electrode of the other device.
Claim 11
Dependent Claim
294 words
A semiconductor device for providing a pair of discrete values of capacitance for a high frequency signal comprising a body of semiconductor material of one type conductivity, a first conductive member insulatingly overlying a surface adjacent region of said body, a second conductive member in electrical contact with another region of said device, means for applying a depletion producing voltage between said first and second conductive members corresponding to a predetermined surface potential having an absolute value less than said depletion producing voltage but greater than the inversion threshold voltage of said device, a first control electrode for controlling the capacitance between said first and second conductive members, means for applying a first control potential to said first control electrode greater than said inversion threshold voltage, a first biasing means for selectively providing a first channel region of opposite type conductivity between said first control electrode and first surface adjacent region, the time constant of the capacitance of said surface adjacent region and the resistance of said second channel region being large in relation to a period of said high frequency signal, a second control electrode for controlling the capacitance between said first and second conductive members, means for applying a second control potential to said second control electrode greater than said inversion threshold voltage, a second biasing means for selectively establishing a second channel region of opposite type conductivity connected between said third electrode and said surface adjacent region, the time constant of the capacitance of said surface adjacent region and the resistance of said second channel region being large in relation to a period of said high frequency signal, means for alternatively rendering operative said first and second biasing means to establish one or the other of said discrete values of capacitance.
Claim 12
Dependent Claim
294 words
A semiconductor device for providing a pair of discrete values of capacitance for a high frequency signal comprising a body of semiconductor material of one type conductivity, a first conductive member insulatingly overlying a surface adjacent region of said body, a second conductive member in electrical contact with another region of said device, means for applying a depletion producing voltage between said first and second conductive members corresponding to a predetermined surface potential having an absolute value less than said depletion producing voltage but greater than the inversion threshold voltage of said device, a first control electrode for controlling the capacitance between said first and second conductive members, means for applying a first control potential to said first control electrode greater than said inversion threshold voltage, a first biasing means for selectively providing a first channel region of opposite type conductivity between said first control electrode and first surface adjacent region, the time constant of the capacitance of said surface adjacent region and the resistance of said second channel region being large in relation to a period of said high frequency signal, a second control electrode for controlling the capacitance between said first and second conductive members, means for applying a second control potential to said second control electrode greater than said inversion threshold voltage, a second biasing means for selectively establishing a second channel region of opposite type conductivity connected between said third electrode and said surface adjacent region, the time constant of the capacitance of said surface adjacent region and the resistance of said second channel region being large in relation to a period of said high frequency signal, means for alternatively rendering operative said first and second biasing means to establish one or the other of said discrete values of capacitance.
Claim 13
Dependent Claim
223 words
Semiconductor apparatus for providing a capacitance for a high frequency signal variable in discrete increments comprising a substrate of semiconductor material of one type conductivity including a plurality of spaced surface adjacent regions, a plurality of capacitance providing electrodes, eAch insulatingly spaced a predetermined distance from a respective surface adjacent region of said substrate and forming with respect to a common electrode connected to said substrate a respective capacitor, said capacitance providing electrodes being coupled together to provide a common capacitance providing electrode of said apparatus, means for applying a depletion producing voltage between said common capacitance providing electrodes and said common electrode corresponding to a predetermined surface potential having an absolute value less than said depletion producing voltage but greater than the inversion threshold voltage of said apparatus, means for applying a high frequency signal between said common capacitance providing electrode and said common electrode, control means for establishing individually in each of said surface adjacent regions a first potential in relation to said substrate corresponding to a respective low value of capacitance between a respective capacitance providing electrode and said common electrode, and for establishing alternatively and individually in each of said surface adjacent regions a second potential in relation to said substrate corresponding to a respective high value of capacitance between a respective capacitance providing electrode and said common electrode.
Claim 14
Dependent Claim
223 words
Semiconductor apparatus for providing a capacitance for a high frequency signal variable in discrete increments comprising a substrate of semiconductor material of one type conductivity including a plurality of spaced surface adjacent regions, a plurality of capacitance providing electrodes, eAch insulatingly spaced a predetermined distance from a respective surface adjacent region of said substrate and forming with respect to a common electrode connected to said substrate a respective capacitor, said capacitance providing electrodes being coupled together to provide a common capacitance providing electrode of said apparatus, means for applying a depletion producing voltage between said common capacitance providing electrodes and said common electrode corresponding to a predetermined surface potential having an absolute value less than said depletion producing voltage but greater than the inversion threshold voltage of said apparatus, means for applying a high frequency signal between said common capacitance providing electrode and said common electrode, control means for establishing individually in each of said surface adjacent regions a first potential in relation to said substrate corresponding to a respective low value of capacitance between a respective capacitance providing electrode and said common electrode, and for establishing alternatively and individually in each of said surface adjacent regions a second potential in relation to said substrate corresponding to a respective high value of capacitance between a respective capacitance providing electrode and said common electrode.
Claim 15
Dependent Claim
49 words
The combination of claim 10 in which the areas of said capacitance providing electrodes are consecutively arranged according to size into a series, each area of the series starting with the second being set in relation to the preceding area of the series to provide twice the capacitance thereof.
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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) | 1978-06-16 | 1978-12-16 | 1979-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-16 | 1982-12-16 | 1983-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-16 | 1986-12-16 | 1987-06-17 | $7700.00 | Window Closed / Lapsed |