Patent Number: 
Section: claims

1. An electron beam apparatus for collecting side-view and plane-view SEM images, the apparatus comprising:an electron source, the electron source providing an electron beam;an objective lens, the objective lens for providing a magnetic immersion function and a retarding function, the objective lens for focusing the electron beam onto a sample surface; andin-lens detectors, the in-lens detectors comprising two or more segments for receiving secondary electrons emanating from the sample surface, each detector segment collecting the secondary electrons emanating from the specimen with related azimuth and polar angle so that a side-view SEM image can be revealed after a signal processing, wherein one of the two or more segments includes an aperture to let the primary electron pass through. 2. The electron beam apparatus of claim 1 in which each of the in-lens detectors comprises at least two or more segments to collect the secondary electrons emanating from the sample with different azimuth angle, the diameter of the aperture being less than 3 millimeters. 3. The electron beam apparatus of claim 1 in which each of the in-lens detectors comprises at least two or more segments to collect the secondary electrons emanating from the sample with a different azimuth angle, one of the detector segments having a small hole on the optical axis to let primary electron pass through, the diameter of the hole being less than 3 millimeters. 4. The electron beam apparatus of claim 1, in which each of the in-lens detectors comprises at least two or more segments to collect the secondary electrons emanating from the sample with different azimuth angle, some of the detector segments forming a small hole on the optical axis to let primary electron pass through, the diameter of the hole being less than 3 millimeters. 5. The electron beam apparatus of claim 1, in which each of the in-lens detectors comprise at least two or more segments being set near by the optical axis of primary beam to collect the secondary electrons emanating from the sample with different azimuth and polar angle, the secondary electrons emanating from the sample with different azimuth and polar angle being guided to the detector by an ExB filter to form a side-view SEM image without affecting the primary beam. 6. A method for collecting side-view and plane-view SEM images, the apparatus comprising:providing an electron beam;providing a magnetic immersion function and a retarding function, the objective lens for focusing the electron beam onto a sample surface; andproviding in-lens detectors, the in-lens detectors comprising two or more segments for receiving secondary electrons emanating from the sample surface, each detector segment collecting the secondary electrons emanating from the specimen with related azimuth and polar angle so that a side-view SEM image can be revealed after a signal processing, wherein one of the two or more segments includes an aperture to let the primary electron pass through. 7. The method of claim 6 in which each of the in-lens detectors comprises at least two or more segments to collect the secondary electrons emanating from the sample with different azimuth angle, the diameter of the aperture being less than 3 millimeters. 8. The method of claim 6 in which each of the in-lens detectors comprises at least two or more segments to collect the secondary electrons emanating from the sample with a different azimuth angle, one of the detector segments having a small hole on the optical axis to let primary electron pass through, the diameter of the hole being less than 3 millimeters. 9. The method of claim 6, in which each of the in-lens detectors comprises at least two or more segments to collect the secondary electrons emanating from the sample with different azimuth angle, some of the detector segments forming a small hole on the optical axis to let primary electron pass through, the diameter of the hole being less than 3 millimeters. 10. The method of claim 6, in which each of the in-lens detectors comprise at least two or more segments being set near by the optical axis of primary beam to collect the secondary electrons emanating from the sample with different azimuth and polar angle, the secondary electrons emanating from the sample with different azimuth and polar angle being guided to the detector by an ExB filter to form a side-view SEM image without affecting the primary beam. 11. An electron beam apparatus for collecting side-view and plane-view SEM images, the apparatus comprising:an electron source, the electron source providing an electron beam;an objective lens, the objective lens for providing a magnetic immersion function and a retarding function, the objective lens for focusing the electron beam onto a sample surface; andin-lens detectors, the in-lens detectors comprising two or more segments for receiving secondary electrons emanating from the sample surface, the segments circling a center wherein the center has no detector, each detector segment collecting the secondary electrons emanating from the specimen with related azimuth and polar angle so that a side-view SEM image can be revealed after a signal processing. 12. The electron beam apparatus of claim 11 in which each of the in-lens detectors comprises at least two or more segments to collect the secondary electrons emanating from the sample with different azimuth angle, the plurality of detector segments forming a small hole on the optical axis to let the primary electron pass through, the diameter of the hole being less than 3 millimeters. 13. The electron beam apparatus of claim 11 in which each of the in-lens detectors comprises at least two or more segments to collect the secondary electrons emanating from the sample with a different azimuth angle, one of the detector segments having a small hole on the optical axis to let primary electron pass through, the diameter of the hole being less than 3 millimeters. 14. The electron beam apparatus of claim 11, in which each of the in-lens detectors comprises at least two or more segments to collect the secondary electrons emanating from the sample with different azimuth angle, some of the detector segments forming a small hole on the optical axis to let primary electron pass through, the diameter of the hole being less than 3 millimeters. 15. The electron beam apparatus of claim 11, in which each of the in-lens detectors comprise at least two or more segments being set near by the optical axis of primary beam to collect the secondary electrons emanating from the sample with different azimuth and polar angle, the secondary electrons emanating from the sample with different azimuth and polar angle being guided to the detector by an ExB filter to form a side-view SEM image without affecting the primary beam.