# US 2008/0185952 A1 · Apparatus for Producing Secondary Electrons, a Secondary Electrode, and an Acceleration Electrode > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2008/0185952 A1 - Document ID: US20080185952A1 - Status: Published application - Kind: A1 - Application number: 12/063,000 - Filed: 2008-04-04 - Published: 2008-08-07 - Earliest claimed: 2002-11-21 - Assignees: Infineon Technologies AG - Inventors: Andreas Kyek - Web page: https://patentgrep.com/patent/US20080185952A1 ## CPC - H01J 43/02: Tubes in which one or a few electrodes are secondary-electron emitting electrodes - H01J 37/026: {Means for avoiding or neutralising unwanted electrical charges on tube components} - H01J 37/06: Electron sources; Electron guns - H01J 2237/0045: using secondary electrons - H01J: ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS (spark-gaps H01T; electric arc lamps H05B31/00; particle accelerators H05H) ## Abstract An apparatus includes a primary electrode and an acceleration electrode. The acceleration electrode or, alternatively, an additional secondary electrode contains a slot that extends obliquely through the acceleration electrode or through the secondary electrode. This measure allows secondary electrons to be produced in a highly effective manner. ## Claims ### Claim 1 An apparatus for producing secondary electrons, comprising: at least one primary electrode for producing primary electrons; an acceleration electrode for accelerating the primary electrons; a secondary electrode for producing secondary electrons when the accelerated primary electrons arrive; and there being a potential of 0 V on the secondary electrode and on the acceleration electrode. ### Claim 2 (depends on 1) The apparatus according to claim 1, wherein: said secondary electrode is formed with at least one aperture opening; said aperture opening extends obliquely through said secondary electrode and/or said aperture opening prevents primary electrons from passing through. ### Claim 3 (depends on 2) The apparatus according to claim 2, wherein said aperture opening is formed by an elongated hole defined by side surfaces configured parallel to one another. ### Claim 4 (depends on 2) The apparatus according to claim 2, wherein: said aperture opening is defined by side surfaces that overlap in a direction at which the primary electrons arrive into said aperture opening. ### Claim 5 (depends on 2) The apparatus according to claim 2, wherein: said secondary electrode has a surface in which said aperture opening is formed; said surface has a normal; and said side surfaces of said aperture opening are configured aligned with said normal. ### Claim 6 (depends on 2) The apparatus according to claim 2, wherein said aperture opening is formed by laminates. ### Claim 7 (depends on 1) The apparatus according to claim 1, wherein: said secondary electrode is formed with at least one aperture opening having an aperture direction configured at an angle of a magnitude of between 30° and 70° with respect to a normal of said secondary electrode near said aperture opening. ### Claim 8 (depends on 7) The apparatus according to claim 7, wherein: said angle has a magnitude of 55° with respect to the normal of said secondary electrode near said aperture opening. ### Claim 9 (depends on 1) The apparatus according to claim 1, wherein: said secondary electrode is formed with at least one aperture opening having an aperture direction configured at an angle defined by: tan(90°−w)=d/b; and w is said angle, d is a thickness of said secondary electrode, and b is a width of said aperture opening. ### Claim 10 (depends on 1) The apparatus according to claim 1, wherein: said secondary electrode has side walls defining an aperture opening; said side walls are spaced a distance apart; and said distance between said side walls is between 2 mm and 6 mm. ### Claim 11 (depends on 10) The apparatus according to claim 10, wherein said distance between said side walls is 4 mm. ### Claim 12 (depends on 1) The apparatus according to claim 1, wherein: said at least one primary electrode includes only one primary electrode. ### Claim 13 (depends on 1) The apparatus according to claim 1, further comprising: a plurality of primary electrodes; said secondary electrode formed with a plurality of aperture openings; each one of said plurality of primary electrodes associated with a respective one of said plurality of aperture openings; and at least one of said plurality of aperture openings being at a different inclination angle than another one of said plurality of aperture openings. ### Claim 14 (depends on 1) The apparatus according to claim 1, wherein: said secondary electrode is formed with at least one aperture opening; said secondary electrode is made of aluminum or of an aluminum alloy. ### Claim 15 (depends on 1) The apparatus according to claim 1, wherein: said secondary electrode is made of Al 99 or of an even purer aluminum. ### Claim 16 (depends on 1) The apparatus according to claim 1, wherein: said secondary electrode is formed with at least one aperture opening; and said secondary electrode is made of graphite or contains at least 60% by mass of graphite. ### Claim 17 (depends on 1) The apparatus according to claim 1, wherein: said secondary electrode is formed with at least one aperture opening; and said secondary electrode is made of aluminum oxide. ### Claim 18 (depends on 1) The apparatus according to claim 1, wherein: said secondary electrode is formed with at least one aperture opening; and said secondary electrode has a mean surface roughness of between 5 and 8 μm. ### Claim 19 (depends on 1) The apparatus according to claim 1, wherein: said acceleration electrode is formed with at least 100 openings. ### Claim 20 (depends on 1) The apparatus according to claim 1, wherein: said acceleration electrode is formed at least 500 openings. ### Claim 21 (depends on 1) The apparatus according to claim 1, wherein: said acceleration electrode is formed with at least 1000 openings. ### Claim 22 (depends on 19) The apparatus according to claim 19, wherein: said acceleration electrode includes a wire mesh having at least 100 holes or meshes. ### Claim 23 (depends on 1) The apparatus according to claim 1, wherein: said acceleration electrode is formed with at least 100 openings; and said acceleration electrode is made of aluminum or an aluminum alloy. ### Claim 24 (depends on 1) The apparatus according to claim 1, wherein: said acceleration electrode is formed with at least 100 openings; and said acceleration electrode is made of Al 99.9 or an even purer aluminum. ### Claim 25 (depends on 1) The apparatus according to claim 1, wherein: said acceleration electrode is formed with at least 100 openings; and said secondary electrode has a mean surface roughness; and said acceleration electrode has a mean surface roughness of less than said mean surface roughness of said secondary electrode. ### Claim 26 (depends on 25) The apparatus according to claim 25, wherein: said mean surface roughness of said acceleration electrode is between 2.5 and 6 μm. ### Claim 27 (depends on 1) The apparatus according to claim 1, further comprising: a free space for an ion beam to pass through; and a workpiece; said ion beam being directed at said workpiece. ### Claim 28 (depends on 27) The apparatus according to claim 27, wherein said workpiece is a semiconductor substrate. ### Claim 29 (depends on 1) The apparatus according to claim 1, further comprising: a free space used for holding a material or workpiece to be processed. ### Claim 30 (depends on 1) The apparatus according to claim 1, further comprising: a free space for an ion beam to pass through; said primary electrode configured parallel to a propagation direction of said ion beam. ### Claim 31 (depends on 1) The apparatus according to claim 1, further comprising: a free space for an ion beam to pass through; said primary electrode configured transversely with respect to a propagation direction of said ion beam.