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CN-121983490-A - Ion implanter and ion angle adjusting method thereof

CN121983490ACN 121983490 ACN121983490 ACN 121983490ACN-121983490-A

Abstract

The application discloses an ion implanter and an ion angle adjusting method thereof, wherein the ion implanter comprises a front structure, a rear structure and an elastic tube connecting the front structure and the rear structure, the front structure comprises an ion source, a leading-out electrode and a mass analysis magnet, the rear structure comprises an analysis slit, a focusing electrode, a scanning electrode and a parallel lens, the ion source, the leading-out electrode, the mass analysis magnet, the analysis slit, the focusing electrode, the scanning electrode and the parallel lens are sequentially arranged, the elastic tube can change the relative positions of the front structure and the rear structure, the ion implanter comprises an offset state of preset ions deviating from the midpoint of the analysis slit, when the ion implanter is in the offset state, the magnetic field of the mass analysis magnet is changed, and the elastic tube enables the relative positions of the front structure and the rear structure to be changed, so that the preset ions can pass through the midpoint of the analysis slit. Through the arrangement, the ion implantation accuracy of the ion implanter can be improved.

Inventors

  • SHEN WENJIE
  • SHE LEI
  • SHEN JIAFU
  • WU JIN
  • PENG JIANBO
  • LIU DAOYUAN

Assignees

  • 浙江求是创芯半导体设备有限公司

Dates

Publication Date
20260505
Application Date
20251231

Claims (10)

  1. 1. An ion implanter (100), comprising: A front structure (18), a rear structure (19) and an elastic tube (20) connecting the front structure (18) and the rear structure (19), wherein the front structure (18) comprises an ion source (11), an extraction electrode (12) and a mass analysis magnet (13), the rear structure (19) comprises an analysis slit (14), a focusing electrode (15), a scanning electrode (16) and a parallel lens (17), and the ion source (11), the extraction electrode (12), the mass analysis magnet (13), the analysis slit (14), the focusing electrode (15), the scanning electrode (16) and the parallel lens (17) are sequentially arranged; -said elastic tube (20) being able to vary the relative position of said front structure (18) and said rear structure (19); The ion implanter (100) comprises an offset state in which preset ions deviate from the midpoint of the analysis slit (14), the magnetic field of the mass analysis magnet (13) changes when the ion implanter (100) is in the offset state, and the elastic tube (20) changes the relative position of the front structure (18) and the rear structure (19) so that the preset ions can pass through the midpoint of the analysis slit (14).
  2. 2. The ion implanter (100) of claim 1, wherein, The ion implanter (100) further comprises a base (21) and a movable substrate (22), wherein the front structure (18) is connected to the movable substrate (22) and is movably connected with the base (21) through the movable substrate (22), and the rear structure (19) is fixedly connected with the base (21).
  3. 3. The ion implanter (100) of claim 1, wherein, The ion implanter (100) further comprises an angle correction magnet (23), wherein the angle correction magnet (23) is positioned on one side of the parallel lens (17) away from the scanning electrode (16), the emission direction of the preset ions passing through the parallel lens (17) is defined as a first preset direction, and the angle correction magnet (23) can enable the preset ions passing through the parallel lens (17) to translate along a second preset direction, and the second preset direction is perpendicular to the first preset direction and parallel to a horizontal plane (101).
  4. 4. The ion implanter (100) of claim 3, The angle correction magnet (23) comprises a magnetic yoke (231), an upper magnetic pole (232), a lower magnetic pole (233) and an excitation coil (234), wherein the upper magnetic pole (232) and the lower magnetic pole (233) are connected to the magnetic yoke (231) and are arranged in opposite directions, the excitation coil (234) is fixed to the magnetic yoke (231), a translation magnetic field is formed between the upper magnetic pole (232) and the lower magnetic pole (233), and the translation magnetic field can enable preset ions passing through the parallel lens (17) to translate along a second preset direction, and the direction of the translation magnetic field is perpendicular to a horizontal plane (101); and defining a plane perpendicular to the first preset direction as a projection plane, wherein the orthographic projection of the preset ions in the projection plane is positioned in the orthographic projection of the translation magnetic field in the projection plane.
  5. 5. A method of ion angle adjustment for an ion implanter (100), adapted for use in an ion implanter (100) according to any of claims 1 to 4, the method comprising: acquiring an offset angle between a preset ion passing through an analysis slit (14) and the middle point of the analysis slit (14); acquiring an initial deflection radius of preset ions passing through a mass analysis magnet (13); based on the initial deflection radius and the offset angle, acquiring a radius difference value between a preset radius and the initial deflection radius, wherein the preset radius is an actual deflection radius of preset ions after the mass analysis magnet (13) adjusts the magnetic field intensity; -obtaining the distance of relative movement of the front structure (18) and the rear structure (19) through the elastic tube (20) based on the offset angle, the radius difference, the first minimum distance of the magnetic field boundary of the mass analysis magnet (13) and the midpoint of the analysis slit (14); And acquiring the magnetic field intensity adjustment quantity of the mass analysis magnet (13) based on the preset radius, the initial deflection radius and the initial magnetic field intensity of the mass analysis magnet (13), wherein the total magnetic field intensity of the magnetic field intensity adjustment quantity and the initial magnetic field intensity is the magnetic field intensity of deflection of the preset ions along the preset radius.
  6. 6. The method of claim 5, wherein, The acquiring the offset angle of the preset ions from the midpoint of the analysis slit (14) when the preset ions pass through the analysis slit (14) comprises: Closing the voltage applied to the scan electrode (16) and the parallel lens (17) so that the preset ions passing through the focusing electrode (15) are not diverged; Placing a faraday cup (24) on a side of the parallel lens (17) away from the scan electrode (16) and moving the faraday cup (24) in a second preset direction, the second preset direction being perpendicular to a preset straight line and parallel to a horizontal plane (101), the preset straight line passing through a midpoint of the analysis slit (14) and parallel to a first preset direction; acquiring a first position of the Faraday cup (24) when passing through the preset straight line; Acquiring a second position when the Faraday cup (24) moves along a second preset direction to measure the current of the preset ion to be maximum; The offset angle is calculated based on a second minimum distance between a magnetic field boundary of the mass analyzing magnet (13) and the faraday cup (24), a distance difference between the first position and the second position along the second preset direction.
  7. 7. The method of claim 6, wherein, The obtaining a radius difference between a preset radius and the initial deflection radius based on the initial deflection radius and the deflection angle includes: The radius difference is calculated based on a ratio of the distance difference to the second minimum distance and based on a product of the ratio and the initial deflection radius.
  8. 8. The method of claim 6, wherein, -Obtaining the distance of relative movement of the front structure (18) and the rear structure (19) through the elastic tube (20) based on the offset angle, the radius difference, the first minimum distance of the magnetic field boundary of the mass analysis magnet (13) from the midpoint of the analysis slit (14), comprising: a distance of relative movement of the front structure (18) and the rear structure (19) through the elastic tube (20) is calculated based on a ratio of the distance difference to the second minimum distance, a product of the ratio and the first minimum distance, and a sum of the radius difference and the product.
  9. 9. The method of claim 5, wherein, The obtaining the magnetic field intensity adjustment amount of the mass analysis magnet (13) based on the preset radius, the initial deflection radius, and the initial magnetic field intensity of the mass analysis magnet (13) includes: The magnetic field strength adjustment amount is calculated based on a negative number of a ratio of the radius difference value to the initial deflection radius, a product of the negative number and the initial magnetic field strength.
  10. 10. The method of claim 9, wherein the ion angle adjustment is performed, Moving the front structure (18) in a direction from the extraction electrode (12) to the ion source (11) when the magnetic field of the mass analysis magnet (13) decreases; when the magnetic field of the mass analysis magnet (13) is enhanced, the front structure (18) is moved in the direction from the ion source (11) to the extraction electrode (12).

Description

Ion implanter and ion angle adjusting method thereof Technical Field The present application relates to semiconductor devices, and more particularly, to an ion implanter and an ion angle adjustment method thereof. Background An ion implanter is a semiconductor doping apparatus for accelerating ions of a specific element and precisely implanting them into a semiconductor material. As shown in fig. 1, the ion implanter includes an ion source, an extraction electrode, a mass analysis magnet, an analysis slit, a focusing electrode, a scanning electrode, and a parallel lens, which are sequentially disposed. Wherein the extraction electrode is capable of extracting ions in the ion source. The mass analysis magnet can screen preset ions (namely ions of required doping elements) in ions led out by the leading-out electrode, specifically, the ions pass through the mass analysis magnet and deflect under the action of lorentz force, so that the preset ions are screened out from all the ions. The analysis slit can be used for passing through the screened preset ions and removing stray ions. The focusing electrode is capable of focusing preset ions passing through the analysis slit. The scan electrode can diverge the preset ions focused by the focus electrode. The parallel lens can emit preset ions after being diverged by the scanning electrode in parallel. By the arrangement, the ion implanter can implant ions of doping elements into the semiconductor material so as to realize the doping process of the semiconductor. In the related art, ions deflect through a mass analysis magnet and then deviate, so that deflected ions cannot be transmitted along an expected path, the ions emitted by the ion implanter deviate, and the ion implantation precision of the ion implanter is reduced. Disclosure of Invention In order to solve the defects in the prior art, the application aims to provide an ion implanter and an ion angle adjusting method thereof, wherein the ion implantation precision is higher. In a first aspect, an embodiment of the present application provides an ion implanter including a front structure including an ion source, an extraction electrode, a scan electrode, and a parallel lens, a rear structure including an analysis slit, a focus electrode, a scan electrode, and a parallel lens, and an elastic tube connecting the front structure and the rear structure, the elastic tube being capable of changing a relative position of the front structure and the rear structure, the ion implanter including an offset state in which a preset ion is offset from a midpoint of the analysis slit, a magnetic field of the mass analysis magnet being changed when the ion implanter is in the offset state, the elastic tube being capable of changing the relative position of the front structure and the rear structure so that the preset ion can pass through the midpoint of the analysis slit. In one possible implementation, the ion implanter further comprises a base and a moving substrate, the front structure is connected to the moving substrate and movably connected to the base by the moving substrate, and the rear structure is fixedly connected to the base. In one possible implementation, the ion implanter further includes an angle correction magnet, the angle correction magnet being located on a side of the parallel lens away from the scan electrode, defining an emission direction of the preset ions passing through the parallel lens as a first preset direction, the angle correction magnet being capable of translating the preset ions passing through the parallel lens along a second preset direction, the second preset direction being perpendicular to the first preset direction and parallel to a horizontal plane. In a possible implementation manner, the angle correction magnet comprises a magnetic yoke, an upper magnetic pole, a lower magnetic pole and an excitation coil, wherein the upper magnetic pole and the lower magnetic pole are connected to the magnetic yoke and are arranged in opposite directions, the excitation coil is fixed on the magnetic yoke, a translation magnetic field is formed between the upper magnetic pole and the lower magnetic pole, the translation magnetic field can enable preset ions passing through the parallel lens to translate along a second preset direction, the direction of the translation magnetic field is perpendicular to a horizontal plane, a plane perpendicular to the first preset direction is defined as a projection plane, and the orthographic projection of the preset ions in the projection plane is in the orthographic projection of the translation magnetic field in the projection plane. In a second aspect, an embodiment of the present application provides an ion angle adjustment method suitable for the above-mentioned ion implanter, the method including: Acquiring an offset angle between a preset ion passing through an analysis slit and the midpoint of the analysis slit; acquiring an initial deflection radius o