1. A method of measuring angular intensity distribution of an illumination beam produced by an illumination system of a lithographic apparatus having an illumination system which is configured to condition a radiation beam and to focus the radiation beam in an object plane, a support constructed to support a patterning device for imparting the radiation beam with a pattern in its cross-section to form a patterned radiation beam, a substrate table constructed to hold a substrate and a projection system configured to project the patterned radiation beam onto a target portion of the substrate, comprising:
placing a detector downstream of said projection system, and measuring an intensity distribution of radiation from said illumination system at said detector to produce a first measurement;
placing a first optical element above said object plane which causes radiation from said illumination system to be deflected in a first direction, and measuring an intensity distribution of said radiation deflected by the first optical element at said detector to produce a second measurement;
placing a second optical element above said object plane which causes radiation from said illumination system to be deflected in a second direction, and measuring an intensity distribution of said radiation deflected by the second optical element at said detector to produce a third measurement; and
using said first, second and third measurements to determine the change in intensity in said first and second directions, and the angular intensity distribution of said illumination beam.
2. A method as in claim 1, wherein said first and second optical elements are the same optical element, and wherein the optical element is used with different rotations when serving as said first and second optical elements.
3. A method as in claim 1, wherein said first and second optical elements are wedges.
4. A method as in claim 1, wherein said first optical element is replaced by the second optical element during said step of placing the second optical element above said object plane.
5. A method as in claim 1, wherein said optical elements are made from synthetic quartz or fused silica.
6. A method as in claim 1, wherein the illumination system and the projection system each have a pupil, and wherein each of said optical elements causes radiation from the same part of the illumination system pupil to pass through a different part of the projection system pupil, and wherein the method includes using this fact to separate the transmission characteristics of the projection system from the illumination distribution of the illumination beam.
7. A method as in claim 1, which further comprises introducing one or more optical elements between the projection system and the detector, and calculating the transmission characteristics of the projection system separately from the response of the detector.
8. A method as in claim 1, which further comprises rotating the detector, and calculating the transmission characteristics of the projection system separately from the response of the detector.
9. A method of measuring the response of a detector to light falling on the detector, the method comprising:
passing light through the projection system of a lithographic apparatus;
positioning the detector downstream of the projection system;
measuring the intensity distribution at said detector to produce a first intensity distribution measurement;
rotating the detector and then measuring the intensity distribution at said detector to produce a second intensity distribution measurement; and
comparing said first and second intensity distribution measurements to calculate the detector response separately from the transmission characteristics of the projection system.
10. A method as in claim 9, further comprising measuring an angular intensity distribution of an illumination beam produced by an illumination system of the lithographic apparatus by:
measuring an intensity distribution of radiation from said illumination system at said detector to produce a first measurement;
placing a first optical element above an object plane of the illumination system of the lithographic apparatus which causes radiation from said illumination system to be deflected in a first direction, and measuring an intensity distribution of said radiation deflected by the first optical element at said detector to produce a second measurement;
placing a second optical element above said object plane which causes radiation from said illumination system to be deflected in a second direction, and measuring an intensity distribution of said radiation deflected by the second optical element at said detector to produce a third measurement; and
using said first, second and third measurements to determine the change in intensity in said first and second directions, and the angular intensity distribution of said illumination beam.
11. A method as in claim 10, wherein said first and second optical elements are the same optical element, and wherein the optical element is used with different rotations when serving as said first and second optical elements.
12. A method as in claim 10, wherein said first and second optical elements are wedges.
13. A method as in claim 10, wherein said first optical element is replaced by the second optical element during said step of placing the second optical element above said object plane.
14. A method as in claim 10, wherein said optical elements are made from synthetic quartz or fused silica.
15. A method as in claim 10, wherein the illumination system and the projection system each have a pupil, and wherein each of said optical elements causes radiation from the same part of the illumination system pupil to pass through a different part of the projection system pupil, and wherein the method includes using this fact to separate the transmission characteristics of the projection system from the illumination distribution of the illumination beam.
16. A method as in claim 10, which further comprises introducing one or more optical elements between the projection system and the detector, and calculating the transmission characteristics of the projection system separately from the response of the detector.
17. A lithographic apparatus, comprising:
an illumination system configured to condition a radiation beam and to focus the radiation beam in an object plane;
a support constructed to support a patterning device, the patterning device arranged to impart the radiation beam with a pattern in its cross-section to form a patterned radiation beam;
a substrate table constructed to hold a substrate;
a projection system configured to project the patterned radiation beam onto a target portion of the substrate;
a detector, positionable downstream of said projection system, configured to measure an intensity distribution of a radiation from the illumination system at said detector to produce a first measurement;
a first optical element, positionable above said object plane, to cause radiation from said illumination system to be deflected in a first direction, the detector is configured to measure an intensity distribution of radiation deflected by the first optical element at said detector to produce a second measurement;
a second optical element, positionable above said object plane, to cause radiation from said illumination system to be deflected in a second direction, the detector configured to measure an intensity distribution of radiation deflected by the second optical element at said detector to produce a third measurement,
wherein the first, second and third measurements are used to determine the change in intensity in said first and second directions, and the angular intensity distribution of said illumination beam.
18. A lithographic apparatus, comprising:
a projection system configured to project a patterned radiation beam onto a target portion of the substrate;
a detector positionable downstream of the projection system and being rotateable,
wherein a response of the detector to radiation falling on the detector is determined by measuring an intensity distribution of light at said detector to produce a first intensity distribution measurement, rotating the detector and then measuring the intensity distribution of light at said detector to produce a second intensity distribution measurement, and comparing said first and second intensity distribution measurements to calculate the detector response separately from the transmission characteristics of the projection system.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A spin valve transistor, comprising:
a collector comprising a III\u2013IV semiconductor;
a first spin valve comprising (100)-oriented metals deposited over the collector;
a spacer disposed over the first spin valve;
a second spin valve comprising (100)-oriented metals deposited over the spacer;
a tunnel barrier layer disposed over the second spin valve; and
an emitter disposed over the tunnel barrier layer.
2. The spin valve transistor of claim 1, wherein the first and second spin valves each comprise a pinned layer, the pinned layers being pinned 180\xb0 out of phase to provide differential detection.
3. The spin valve transistor of claim 1, wherein the first and second spin valves comprises a first magnetic layer, a non-magnetic layer disposed over the first magnetic layer and a second magnetic layer disposed over the non-magnetic layer.
4. The spin valve transistor of claim 3, wherein the first and second magnetic layers comprise an iron film.
5. The spin valve transistor of claim 4, wherein the non-magnetic layer comprises a gold film.
6. The spin valve transistor of claim 3, wherein the non-magnetic layer comprises a gold film.
7. The spin valve transistor of claim 1, wherein the collector comprises an n-GaAs substrate.
8. The spin valve transistor of claim 1, wherein the spacer comprises a (100)-oriented layer of gold.
9. The spin valve transistor of claim 1, wherein the tunnel barrier layer comprises a layer of Al2O3.
10. The spin valve transistor of claim 1, wherein the emitter comprises a layer of aluminum disposed over the tunnel barrier layer and a layer of gold disposed over the aluminum.
11. A magnetic storage device, comprising:
at least one magnetic storage medium;
a motor for moving the at least one magnetic storage medium;
a magnetoresistive sensor for reading data on the at least one magnetic storage medium, and
an actuator assembly, coupled to the ballistic magnetoresistive sensor, for moving the ballistic magnetoresistive sensor relative to the at least one magnetic storage medium;
wherein the magnetoresistive sensor further comprising a spin valve transistor, the spin valve transistor including:
a collector comprising a III\u2013IV semiconductor;
a first spin valve comprising (100)-oriented metals deposited over the collector;
a spacer disposed over the first spin valve;
a second spin valve comprising (100)-oriented metals deposited over the spacer;
a tunnel barrier layer disposed over the second spin valve; and
an emitter disposed over the tunnel barrier layer.
12. The magnetic storage device of claim 11, wherein the first and second spin valves each comprise a pinned layer, the pinned layers being pinned 180\xb0 out of phase to provide differential detection.
13. The magnetic storage device of claim 11, wherein the first and second spin valves comprises a first magnetic layer, a non-magnetic layer disposed over the first magnetic layer and a second magnetic layer disposed over the non-magnetic layer.
14. The magnetic storage device of claim 13, wherein the first and second magnetic layers comprise an iron film.
15. The magnetic storage device of claim 14, wherein the non-magnetic layer comprises a gold film.
16. The magnetic storage device of claim 13, wherein the non-magnetic layer comprises a gold film.
17. The magnetic storage device of claim 11, wherein the collector comprises an n-GaAs substrate.
18. The magnetic storage device of claim 11, wherein the spacer comprises a (100)-oriented layer of gold.
19. The magnetic storage device of claim 11, wherein the tunnel barrier layer comprises a layer of Al2O3.
20. The magnetic storage device of claim 11, wherein the emitter comprises a layer of aluminum disposed over the tunnel barrier layer and a layer of gold disposed over the aluminum.
21. A method for forming a spin valve transistor, comprising:
forming a collector comprising a III\u2013IV semiconductor;
forming a first spin valve comprising (100)-oriented metals deposited over the collector;
forming a spacer over the first spin valve;
forming a second spin valve comprising (100)-oriented metals over the spacer;
forming a tunnel barrier layer over the second spin valve; and
forming an emitter over the tunnel barrier layer.
22. The spin valve transistor of claim 21, wherein the forming the first and second spin valves further comprises forming a pinned layer pinned 180\xb0 out of phase in each of the first and second spin valves to provide differential detection.
23. The spin valve transistor of claim 21, wherein the forming the first and second spin valves further comprises forming a first magnetic layer, forming a non-magnetic layer over the first magnetic layer and forming a second magnetic layer disposed over the non-magnetic layer.
24. The spin valve transistor of claim 23, wherein the forming the first and second magnetic layers further comprises forming a first and second iron film.
25. The spin valve transistor of claim 24, wherein the forming the non-magnetic layer further comprises forming a gold film.
26. The spin valve transistor of claim 23, wherein the forming the non-magnetic layer further comprises forming a gold film.
27. The spin valve transistor of claim 21, wherein the forming the collector further comprises forming an n-GaAs substrate.
28. The spin valve transistor of claim 21, wherein the forming the spacer further comprises forming a (100)-oriented layer of gold.
29. The spin valve transistor of claim 21, wherein the forming the tunnel barrier layer further comprises forming a layer of Al2O3.
30. The spin valve transistor of claim 21, wherein the forming the emitter further comprises forming a layer of aluminum over the tunnel barrier layer and forming a layer of gold over the aluminum.
31. A spin valve transistor, comprising:
means for providing a collector comprising a III\u2013IV semiconductor;
means for providing a first spin valve comprising (100)-oriented metals deposited over the means for providing a collector;
means for providing a spacer disposed over the means for providing a first spin valve;
means for providing a second spin valve comprising (100)-oriented metals deposited over the means for providing a spacer;
means for providing a tunnel barrier layer disposed over the means for providing a second spin valve; and
means for providing an emitter disposed over the means for providing a tunnel barrier layer.
32. A magnetic storage device, comprising:
means for recording magnetic data thereon;
means for moving the means for recording magnetic data;
means for reading data on the means for recording magnetic data; and
means, coupled to the means for reading, for moving the means for reading relative to the means for storing data, wherein the means for reading further comprising:
means for providing a collector comprising a III\u2013IV semiconductor;
means for providing a first spin valve comprising (100)-oriented metals deposited over the means for providing a collector;
means for providing a spacer disposed over the means for providing a first spin valve;
means for providing a second spin valve comprising (100)-oriented metals deposited over the means for providing a spacer;
means for providing a tunnel barrier layer disposed over the means for providing a second spin valve; and
means for providing an emitter disposed over the means for providing a tunnel barrier layer.