Claims
- 1. An imaging device comprising:
a plurality of pixel elements, each pixel element including complementary first-type and second-type modulation doped quantum well interfaces that are formed in a resonant cavity on a substrate and that are spaced apart from one another, wherein electromagnetic radiation within a predetermined wavelength range is received at said pixel element and injected into said resonant cavity thereby generating charge that is accumulated in said second-type modulation doped quantum well interface for said pixel element.
- 2. An imaging device according to claim 1, wherein:
the amount of charge accumulated in said second-type modulation doped quantum well interface for said pixel element is proportional to power of the electromagnetic radiation within the predetermined wavelength range that is received at said pixel element.
- 3. An imaging device according to claim 1, wherein:
the electromagnetic radiation within the predetermined wavelength range increases electron temperature of a two-dimensional electron gas at said first-type modulation doped quantum well interface thereby producing a current resulting from thermionic emission over a potential barrier provided by said first-type modulation doped quantum well interface, wherein said current results in accumulation of charge in said second-type modulation doped quantum well interface.
- 4. An imaging device according to claim 3, wherein:
said current is proportional to power of the electromagnetic radiation within the predetermined wavelength range that is received at the pixel element.
- 5. An imaging device according to claim 1, wherein:
said first-type modulation doped quantum well interface and said second-type modulation doped quantum well interface are spaced apart from one another in a vertical dimension.
- 6. An imaging device according to claim 1, wherein:
each pixel element is adapted to operate in at least one of the following modes:
i) a pixel setup mode whereby charge is emptied from said second-type modulation doped quantum well interface for said pixel element; ii) a signal integration mode whereby charge is accumulated in said second-type modulation doped quantum well interface over an integration time period; and iii) a signal transfer mode whereby charge is read out from said second-type modulation doped quantum well interface.
- 7. An imaging device according to claim 6, wherein:
each pixel element is adapted to perform a sequence of imaging cycles, each cycle including said pixel setup mode, said signal integration mode, and said signal transfer mode.
- 8. An imaging device according to claim 6, wherein:
free charge is emptied from said first-type modulation doped quantum well interface during said signal transfer mode.
- 9. An imaging device according to claim 6, wherein:
charge is transferred between pixel elements in said signal transfer mode to thereby realize a CCD-type imaging array.
- 10. An imaging device according to claim 9, wherein:
charge is transferred between pixel elements over a pathway defined by a second-type modulation doped interface between pixel elements.
- 11. An imaging device according to claim 10, wherein:
said second-type modulation doped interface between pixel elements is doped with donor ions to increase carrier density.
- 12. An imaging device according to claim 10, wherein:
length of said second-type modulation doped interface between pixel elements is selected for desired charge velocity between pixel elements.
- 13. An imaging device according to claim 1, wherein:
each pixel element includes an undoped spacer layer disposed between said first-type modulation doped quantum well interface and said second-type modulation doped quantum well interface.
- 14. An imaging device according to claim 13, wherein:
each pixel element includes
at least one first-type ion implant in electrical contact with said first-type modulation doped quantum well interface, and second-type ions implants in electrical contact with said second-type modulation doped quantum well interface.
- 15. An imaging device according to claim 14, wherein:
each pixel element includes
at least one first channel injector terminal formed from a metal layer deposited on said at least one first-type ion implant, and second channel injector terminals formed from a metal layer deposited on said second-type ion implants.
- 16. An imaging device according to claim 15, wherein:
each pixel element includes
an anode and cathode formed such that said first-type modulation doped quantum well interface and said second-type modulation doped quantum well interface are disposed between said anode and said cathode, an anode terminal electrically coupled to said anode, and a cathode terminal electrically coupled to said cathode to thereby integrally forming a thyristor-based pixel element on said substrate.
- 17. An imaging device according to claim 16, further comprising:
circuitry, electrically coupled to a second channel injector for a given pixel element in a pixel setup mode, that empties free charge from said second-type modulation doped quantum well interface for said given pixel element in said pixel setup mode.
- 18. An imaging device according to claim 16, wherein:
said second-type modulation doped quantum well interface for each pixel element includes a potential barrier portion and a charge storage portion, said charge storage portion formed via a threshold-adjusting ion implant therein, said potential barrier portion disposed under said anode terminal and providing a voltage-controlled potential barrier.
- 19. An imaging device according to claim 18, wherein:
circuitry, electrically coupled to the anode terminals for said pixel elements, that applies clock pulses to said anode terminals to transfer charge between adjacent pixel elements utilizing voltage-controlled adjustment of said potential barrier provided by said potential barrier portion of said pixel elements.
- 20. An imaging device according to claim 16, further comprising:
circuitry, electrically coupled to a first channel injector terminal for a given pixel element in a signal transfer mode, that empties free charge from said first-type modulation doped quantum well interface for said given pixel element in said signal transfer mode.
- 21. An imaging device according to claim 16, further comprising:
electronic shutter circuitry, electrically coupled to said cathode terminal for a given pixel element, that selectively operates to couple said cathode terminal to a load element or place said cathode terminal in a high-impedance state.
- 22. An imaging device according to claim 21, wherein:
said electronic shutter circuitry couples said cathode terminal for the given pixel element to a load element during a signal integration mode whereby charge is accumulated in said second-type modulation doped quantum well interface for the given pixel element.
- 23. An imaging device according to claim 21, wherein:
said electronic shutter circuitry places said cathode terminal for the given pixel element in a high-impedance state during at least one of
a pixel setup mode whereby charge is emptied from said second-type modulation doped quantum well interface for the given pixel element, and a signal transfer mode whereby charge is read out from said second-type modulation doped quantum well interface for the given pixel element.
- 24. An imaging device according to claim 1, wherein:
said plurality of pixel elements are part of a full-frame-type imaging array.
- 25. An imaging device according to claim 1, wherein:
said plurality of pixel elements are part of an interline-type imaging array.
- 26. An imaging device according to claim 1, wherein:
said plurality of pixel elements are part of an active-pixel-type imaging array.
- 27. A method of generating an image of received electromagnetic radiation within a predetermined wavelength range comprising:
providing a plurality of pixel elements, each pixel element including complementary first-type and second-type modulation doped quantum well interfaces that are formed in a resonant cavity on a substrate and that are spaced apart from one another, wherein electromagnetic radiation within the predetermined wavelength range is received at said pixel element and injected into said resonant cavity; adapting said pixel elements to operate in a signal integration mode whereby charge is accumulated in said second-type modulation doped quantum well interface of said pixel elements over an integration time period.
- 28. A method according to claim 27, wherein:
the amount of charge accumulated in said second-type modulation doped quantum well interface for said pixel element is proportional to power of the electromagnetic radiation within the predetermined wavelength range that is received at said pixel element.
- 29. A method according to claim 27, wherein:
the electromagnetic radiation within the predetermined wavelength range increases electron temperature of a two-dimensional electron gas at said first-type modulation doped quantum well interface thereby producing a current resulting from thermionic emission over a potential barrier provided by said first-type modulation doped quantum well interface, wherein said current results in accumulation of charge in said second-type modulation doped quantum well interface.
- 30. A method according to claim 29, wherein:
said current is proportional to power of the electromagnetic radiation within the predetermined wavelength range that is received at the pixel element.
- 31. A method according to claim 27, wherein:
said first-type modulation doped quantum well interface and said second-type modulation doped quantum well interface are spaced apart from one another in a vertical dimension.
- 32. A method according to claim 27, wherein:
each pixel element is adapted to operate in at least one of the following modes:
i) a pixel setup mode whereby charge is emptied from said second-type modulation doped quantum well interface for said pixel element; and ii) a signal transfer mode whereby charge is read out from said second-type modulation doped quantum well interface.
- 33. A method according to claim 32, wherein:
each pixel element is adapted to perform a sequence of imaging cycles, each cycle including said pixel setup mode, said signal integration mode, and said signal transfer mode.
- 34. A method according to claim 32, wherein:
free charge is emptied from said first-type modulation doped quantum well interface during said signal transfer mode.
- 35. A method according to claim 32, wherein:
charge is transferred between pixel elements in said signal transfer mode to thereby perform CCD-type imaging operations.
- 36. A method according to claim 35, wherein:
charge is transferred between pixel elements over a pathway defined by a second-type modulation doped interface between pixel elements.
- 37. A method according to claim 36, wherein:
said second-type modulation doped interface between pixel elements is doped with donor ions to increase carrier density.
- 38. A method according to claim 36, wherein:
length of said second-type modulation doped interface between pixel elements is selected for desired charge velocity between pixel elements.
- 39. A method according to claim 27, wherein:
each pixel element includes an undoped spacer layer disposed between said first-type modulation doped quantum well interface and said second-type modulation doped quantum well interface.
- 40. A method according to claim 39, wherein:
each pixel element includes
at least one first-type ion implant in electrical contact with said first-type modulation doped quantum well interface, and second-type ions implants in electrical contact with said second-type modulation doped quantum well interface.
- 41. A method according to claim 40, wherein:
each pixel element includes
at least one first channel injector terminal formed from a metal layer deposited on said at least one first-type ion implant, and second channel injector terminals formed from a metal layer deposited on said second-type ion implants.
- 42. A method according to claim 41, wherein:
each pixel element includes
an anode and cathode formed such that said first-type modulation doped quantum well interface and said second-type modulation doped quantum well interface are disposed between said anode and said cathode, an anode terminal electrically coupled to said anode, and a cathode terminal electrically coupled to said cathode to thereby integrally forming a thyristor-based pixel element on said substrate.
- 43. A method according to claim 42, further comprising:
emptying free charge from said second-type modulation doped quantum well interface for said given pixel element in a pixel setup mode.
- 44. A method according to claim 42, wherein:
said second-type modulation doped quantum well interface for each pixel element includes a potential barrier portion and a charge storage portion, said charge storage portion formed via a threshold-adjusting ion implant therein, said potential barrier portion disposed under said anode terminal and providing a voltage-controlled potential barrier.
- 45. A method according to claim 44, further comprising:
applying clock pulses to said anode terminals to transfer charge between adjacent pixel elements utilizing voltage-controlled adjustment of said potential barrier provided by said potential barrier portion of said pixel elements.
- 46. A method according to claim 42, further comprising:
emptying free charge from said first-type modulation doped quantum well interface for said given pixel element in a signal transfer mode.
- 47. A method according to claim 42, further comprising:
selectively coupling said cathode terminal to a load element during a signal integration mode whereby charge is accumulated in said second-type modulation doped quantum well interface for the given pixel element.
- 48. A method according to claim 42, further comprising:
placing said cathode terminal for the given pixel element in a high-impedance state during at least one of a pixel setup mode whereby charge is emptied from said second-type modulation doped quantum well interface for the given pixel element, and a signal transfer mode whereby charge is read out from said second-type modulation doped quantum well interface for the given pixel element.
- 49. A method according to claim 27, wherein:
said plurality of pixel elements are part of a full-frame-type imaging array.
- 50. A method according to claim 27, wherein:
said plurality of pixel elements are part of an interline-type imaging array.
- 51. A method according to claim 27, wherein:
said plurality of pixel elements are part of an active-pixel-type imaging array.
Parent Case Info
[0001] This is a continuation-in-part of U.S. Ser. No. 09/556,285 to Taylor, filed Apr. 24, 2000 and entitled “A III-V Charge Coupled Device Suitable for Visible Near and Far Infrared Detection”, and a continuation-in-part of International Application No. PCT/US02/06802 to Taylor filed Mar. 4, 2002, and a continuation-in-part of International Application No. PCT/US03/13183 to Taylor filed Apr. 28, 2003, all of which are hereby incorporated by reference herein in their entireties.
Continuation in Parts (3)
|
Number |
Date |
Country |
Parent |
09556285 |
Apr 2000 |
US |
Child |
10689019 |
Oct 2003 |
US |
Parent |
PCT/US02/06802 |
Mar 2002 |
US |
Child |
10689019 |
Oct 2003 |
US |
Parent |
PCT/US03/13183 |
Apr 2003 |
US |
Child |
10689019 |
Oct 2003 |
US |