Patent Number: 
Section: claims

1. A charged particle beam apparatus having an opening formation member formed with an opening for passage of a charged particle beam emitted from a charged particle source, and either a detector adapted to detect charged particles emitted from a sample and having passed through said passage opening or a detector adapted to detect charged particles resulting from bombardment on another member of the charged particles having passed through said passage opening, comprising:an aligner for aligning charged particles emitted from said sample and a control unit for controlling said aligner, wherein said control unit controls the aligner to cause it to shift trajectories of the charged particles emitted from said sample so that length measurement may be executed on the basis of detection signals before and after the alignment by said aligner. 2. A charged particle beam apparatus according to claim 1, wherein said aligner is a Wien filter. 3. A charged particle beam apparatus according to claim 1, wherein said control unit changes the alignment status of said aligner into at least two statuses and the length measurement is executed by using signal waveforms obtained in said two alignment statuses. 4. A charged particle beam apparatus according to claim 1, wherein said control unit executes the length measurement by using one of signal waveforms obtained when the alignment condition of said aligner is changed in plural manners, said one signal waveform having a peak height which satisfies a predetermined condition. 5. A charged particle beam apparatus according to claim 1, wherein said another member is a conversion electrode adapted to generate electrons under bombardment of charged particles emitted from said sample. 6. A charged particle beam apparatus according to claim 1, wherein said control unit selects an alignment direction by said aligner in accordance with a direction of said length measurement. 7. A charged particle beam apparatus having an opening formation member formed with an opening for passage of a charged particle beam emitted from a charged particle source, and either a detector adapted to detect charged particles emitted from a sample and having passed through said passage opening or a detector adapted to detect charged particles resulting from bombardment on another member of the charged particles having passed through said passage opening, comprising:an aligner for aligning charged particles emmited from said sample and a control unit for controlling said aligner, wherein said control unit forms a signal waveform on the basis of an output of said detector, aligns charged particles emmited from said sample such that a brightness a peak of said signal waveform shows satisfies a predetermined condition, and executes length measurement of a pattern dimension on said sample by using a signal waveform obtained on the basis of said alignment. 8. A charged particle beam apparatus according to claim 7, wherein said aligner is a Wien filter. 9. A charged particle beam apparatus according to claim 7, wherein said control unit executes said length measurement by using a peak top of a signal waveform obtained when the alignment status of said aligner is changed by plural times or a peak having a brightness of a predetermined value or more. 10. A charged particle beam apparatus according to claim 7, wherein said another member is a conversion electrode adapted to generate electrons under bombardment of charged particles emitted from said sample. 11. A charged particle beam apparatus according to claim 7, wherein said control unit selects an alignment direction by said aligner in accordance with a direction of said length measurement. 12. A charged particle beam apparatus having an opening formation member formed with an opening for passage of a charged particle beam emitted from a charged particle source, and either a detector adapted to detect charged particles emitted from a sample and having passed through said passage opening or a detector adapted to detect charged particles resulting from bombardment on another member of the charged particles having passed through said passage opening, comprising:an aligner for aligning charged particles emitted from said sample and a control unit for controlling said aligner, wherein said control unit judges a line and/or space formed on sample on the basis of a signal waveform detected after alignment by means of said aligner.