Claims
- 1. A method of forming an electronic device comprising the steps of:forming a first conductive material capable of conducting an electrical current along a first path; forming a second ferromagnetic material with a magnetization state that is magnetically coupled to a substantial portion of said current in said first material; and forming an isolation element coupled to the first material for isolating such first material.
- 2. The method of claim 1, wherein an electrical signal can be generated as an output from the first material based on the magnetic coupling, and the isolation element is coupled to and isolates such output.
- 3. The method of claim 2, further including a step of forming a sensing circuit for receiving the electrical signal from the isolation element.
- 4. The method of claim 3, wherein the magnetization state corresponds to a data value, and the data value can be determined from the electrical signal received by the sensing circuit.
- 5. The method of claim 4, further including a step of forming a bias source coupled to the first material for generating the electrical current.
- 6. The method of claim 5, wherein as formed the isolation element includes a transistor, and the sensing circuit receives the electrical signal in response to a select signal applied to the transistor.
- 7. The method of claim 5, wherein as formed the isolation element is a diode or resistor, and the sensing circuit receives the electrical signal in response to a select signal applied to the first material.
- 8. The method of claim 1, further including a step of forming a write circuit for setting the magnetization state of the ferromagnetic layer.
- 9. The method of claim 1, wherein the magnetization state of the ferromagnetic material is configurable and non-volatile.
- 10. The method of claim 1, wherein said ferromagnetic layer is formed to overly approximately ½ an area of such hall effect device.
- 11. The method of claim of claim 8, wherein said write circuit is formed to include a row write wire carrying a row signal, and a column write wire carrying a column signal, and said magnetization state is adjustable only when both said row and column signals combine to generate a sufficiently large write magnetic field to alter said magnetization state.
- 12. A method of forming a memory circuit for storing a data value comprising the steps of:forming a magnetoelectronic element having a ferromagnetic layer with a magnetization state representing the data value, said magnetoelectronic element being configured so that an output signal based on said magnetization state can be generated and provided at a data output; forming an isolation element for isolating said magnetoelectronic element from electrical disturbances that may affect said data value; and wherein the output signal can be selectively read from said memory circuit with a select signal to determine the data value.
- 13. The method of claim 12, further including a step of forming a hall effect device, and wherein said magnetization state is coupled to an electrical current carried in said hall effect device.
- 14. The method of claim 12, further including a step of forming a bias source coupled to the hall effect device for generating an electrical current in such device.
- 15. The method of claim 12, wherein said isolation element is a FET that isolates said data output.
- 16. The method of claim 12, wherein said isolation element is a diode or resistor that isolates said data output unless said select signal is applied to the memory circuit.
- 17. The method of claim 12, wherein the data value is configurable and non-volatile.
- 18. The method of claim 13, wherein said ferromagnetic layer overlies approximately ½ an area of such hall effect device.
- 19. The method of claim 13, further including a step of forming a bias source, said bias source maintaining a bias signal to said hall effect device so that said electrical current is generated at all times said memory circuit is operated.
- 20. The method of claim 12, further including a step of forming a write circuit for writing the data value, said write circuit including a row write wire carrying a row signal, and a column write wire carrying a column signal, and said magnetization state is adjustable only when both said row and column signals combine to generate a sufficiently large write magnetic field to alter said magnetization state.
- 21. A method of forming a memory circuit for storing a data value comprising the steps of:forming a magnetoelectronic element having a ferromagnetic layer with a magnetization state corresponding to the data value; and forming a first write line that is inductively coupled to said ferromagnetic layer; and forming a second write line that is inductively coupled to said ferromagnetic layer; and said first and second write lines being arranged with respect to the ferromagnetic layer such that the presence of a single write signal on only one of said first and/or second write lines generates a magnetic field that is insufficient to alter said magnetization state.
- 22. The method of claim 21, wherein said first and second write lines are formed such that when said single write signal is present on said first or second write lines it generates a magnetic field having a coercivity that is greater than ½ of that of the ferromagnetic layer.
- 23. The method of claim 21, wherein a first write signal on said first write line and a second write signal on said second write line are required at the same time to alter said magnetization state.
- 24. The method of claim 21, wherein said first or second write line also form a read line.
- 25. A method of making a memory circuit for storing a data value comprising the steps of:forming a magnetoelectronic element having a ferromagnetic layer with a magnetization state representing the data value; and forming a first write line inductively coupled to said ferromagnetic layer; forming a second write line inductively coupled to said ferromagnetic layer; wherein said data value is alterable only in response a first write signal and a second write signal being present on said first and second write lines respectively at the same time.
- 26. The method of claim 25, wherein said first and second write lines are formed such that said first write signal and said second write signal each generate a magnetic field having a coercivity that is greater than ½ of that of the ferromagnetic layer.
- 27. The method of claim 25, wherein said first or second write line also form a read line.
RELATED APPLICATIONS
The present invention is a continuation-in-part of the following prior applications by the present applicant:
(1) an application titled “Magnetic Spin Transistor, Logic Gate & Method of Operation,” (Ser. No. 08/425,884, filed Apr. 21, 1995, issued May 13, 1997 as U.S. Pat. No. 5,629,549);
(2) an application titled “Magnetic Spin Transistor Hybrid Circuit Element,” (Ser. No. 08/493,815, filed Jun. 22, 1995 issued Oct. 15, 1996 as U.S. Pat. No. 5,565,695);
(3) an application titled “Magnetic Spin Injected Field Effect Transistor and Method of Operation,” (Ser. No. 08/643,804 filed May 6, 1996, issued Aug. 5, 1997 as U.S. Pat. No. 5,654,566);
(4) an application titled “Hybrid Hall Effect Device and Method of Operation,” (Ser. No. 08/643,805, filed May 6, 1996, issued Jul. 27, 1997 as U.S. Pat. No. 5,652,445)
The present application is also a continuation of application of Ser. No. 08/806,028 filed Feb. 24,1997, now U.S. Pat. No. 6,064,083.
The above materials are expressly incorporated by reference herein.
Government Interests
The government of the United States may have certain limited rights in the present invention.
US Referenced Citations (28)
Non-Patent Literature Citations (13)
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Continuations (1)
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Continuation in Parts (4)
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08/425884 |
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08/493815 |
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