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CN114438462A - Densification film forming method for secondary electron emission thin film - Google Patents

Densification film forming method for secondary electron emission thin film Download PDF

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Publication number
CN114438462A
CN114438462A CN202111602863.2A CN202111602863A CN114438462A CN 114438462 A CN114438462 A CN 114438462A CN 202111602863 A CN202111602863 A CN 202111602863A CN 114438462 A CN114438462 A CN 114438462A
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film
electron emission
secondary electron
plasma generator
magnetron sputtering
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Inventor
郭磊
崔敬忠
王多书
刘志栋
陈江
杨炜
涂建辉
侍椿科
王骥
马寅光
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Lanzhou Institute of Physics of CAST
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Lanzhou Institute of Physics of CAST
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    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
    • C23C14/34—Sputtering
    • C23C14/35—Sputtering by application of a magnetic field, e.g. magnetron sputtering
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/06—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the coating material
    • C23C14/08—Oxides
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/06—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the coating material
    • C23C14/08—Oxides
    • C23C14/081—Oxides of aluminium, magnesium or beryllium
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/06—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the coating material
    • C23C14/10—Glass or silica

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physical Vapour Deposition (AREA)

Abstract

The invention discloses a secondary electron emission thin film densification film forming method. The invention adopts a new method of magnetron sputtering technology plating under the assistance of plasma, enhances the energy of film forming ions through the plasma generated by an ion source, degrades the film forming large particles, and improves the density of the film layer, thereby improving the bombardment capability of the secondary electron emission film for tolerating cesium ions and electrons. The invention can reduce the attenuation rate index of the electron multiplier to be below 0.2V/day and can increase the service life index of the electron multiplier to be more than 12 years.

Description

Densification film forming method for secondary electron emission thin film
Technical Field
The invention relates to the technical field of electron multipliers, in particular to a secondary electron emission thin film densification film forming method.
Background
An electron multiplier is an electric vacuum device for amplifying weak signals, and can be applied to the fields of cesium atomic clocks, mass spectrometers, surface analysis instruments and the like, and generally adopts a multi-dynode structure, as shown in fig. 2, d1-d9 are first to ninth dynodes, a first dynode d1 is also called a cathode K, a ninth dynode is an end dynode E, A is an anode, namely a collector, and R1-R9 are divider resistors. When a negative high voltage is loaded between a cathode K and an end dynode E, an electric field is generated between adjacent dynodes through a divider resistor R, a first dynode emits secondary electrons under the bombardment of cesium ions, the generated secondary electrons are incident to a second dynode under the action of the electric field, the second dynode is excited to generate secondary electrons, and by analogy, the secondary electrons amplified by multi-stage multiplication are finally received by a collector A and output for detection.
The preparation of a secondary electron emission film (as shown in fig. 2) on the inner surface of the handling stage is the key to the signal amplification of the electron multiplier. In the using process, the secondary electron emission film on the electron multiplier beating stage continuously emits electrons due to the incidence of ions and electrons, and finally, ion signals are converted into electronic signals which are amplified in multiple stages for signal verification. Due to the high energy, the continuous incidence of cesium ions and electrons actually causes structural damage of the secondary electron emission film. Under the continuous bombardment of high-energy ions and large beam gain electron beams, the emission coefficient of the secondary electron emission film is gradually reduced, and the gain current value of the electron multiplier is gradually reduced, which is the main reason for the failure of the electron multiplier.
The capability of the secondary electron emission film to resist ion and electron bombardment is the key to ensure the long service life of the electron multiplier. The density of the secondary electron emission film is improved, and the method is an important way for improving the ion resistance and electron emission bombardment capability of the secondary electron emission film. The existing preparation method of the electron multiplier secondary electron emission film comprises an Ag-Mg alloy sensitization method and a magnetron sputtering method, and due to different film forming modes, the magnetron sputtering method has higher density and longer service life than the secondary electron emission film prepared by the Ag-Mg alloy sensitization method. However, due to the limitation of film-forming ion energy, the magnetron sputtering method cannot continuously improve the density of the secondary electron emission film, and the service life of the electron multiplier still has problems.
Disclosure of Invention
In view of the above, the present invention provides a method for densifying and forming a film of a secondary electron emission thin film, which adopts a plasma-assisted magnetron sputtering technology, i.e., introduces plasma in the magnetron sputtering coating process, degrades large particles with poor adhesion, improves the compactness of the secondary electron emission thin film, and improves the ion and electron bombardment resistance of the thin film, thereby improving the service life of the electron multiplier.
The invention relates to a secondary electron emission film densification film-forming method, wherein a plasma generator is arranged in a magnetron sputtering film-coating cavity; and the plasma generator is synchronously started in the magnetron sputtering coating process, generates plasma, and plays roles in increasing the energy of film forming particles, eroding large-size particles and enhancing the compactness and the adhesion of a film layer.
Preferably, the plasma generator is an end Hall type ion source; the discharge voltage of the end Hall ion source is 50-300V, the discharge current is 1-15A, the ion energy is distributed in 10-140 eV, and the ion beam divergence angle is 25-75 degrees.
Preferably, the plasma generator is arranged in the magnetron sputtering coating cavity, and the emission surface of the plasma generator points to the central position of the magnetron sputtering substrate frame; the connecting line of the central point of the emitting surface and the central point of the substrate frame forms an included angle alpha with the axis of the substrate frame, and the alpha is 30-60 degrees; the height H of the horizontal plane of the central point of the emitting surface from the horizontal plane of the substrate frame is 10-30 cm.
Preferably, the secondary electron emission film is MgO or Al2O3Or SiO2A film.
Preferably, platingIn the film coating process, the film coating pressure is 1-2 mTorr, the magnetron sputtering power is 120-200W, a plasma generator is synchronously started, the plasma generator power is 50-150W, and the film layer deposition rate is greater than or equal to
Figure BDA0003433500900000031
Has the advantages that:
the invention adopts a new method of magnetron sputtering technology plating under the assistance of plasma, enhances the energy of film forming ions through the plasma generated by an ion source, degrades the film forming large particles, and improves the density of the film layer, thereby improving the bombardment capability of the secondary electron emission film for tolerating cesium ions and electrons. The invention can reduce the attenuation rate index of the electron multiplier to be below 0.2V/day and can increase the service life index of the electron multiplier to be more than 12 years.
Drawings
FIG. 1 is a schematic diagram of the operation of an electron multiplier;
FIG. 2 is a schematic diagram of an electron multiplier dozen stages;
FIG. 3 is a schematic view of an installation structure of a vacuum chamber ion source of the magnetron sputtering device;
FIG. 4 is a comparison of X-ray diffraction analysis of MgO thin film prepared by plasma-assisted magnetron sputtering and magnetron sputtering;
FIG. 5 is a graph of electron multiplier operating voltage.
Detailed Description
The invention is described in detail below by way of example with reference to the accompanying drawings.
The invention provides a secondary electron emission film densification film-forming method, wherein a plasma generator is arranged in magnetron sputtering film-coating equipment, and the plasma generator is synchronously started in the film-coating process to generate plasma and bombard a deposition surface, thereby achieving the purposes of increasing the energy of film-forming particles, denudating large-size particles and enhancing the compactness and adhesive force of a film layer.
In the embodiment, an end Hall type ion source is used as a plasma generator, the discharge voltage is 50V-300V, the discharge current is 1A-15A, the ion energy is distributed in 10eV-140eV, the ion beam divergence angle is 25-75 degrees, and the device can be completely suitable for introducing oxygen, nitrogen and other reaction gases in the magnetron sputtering deposition process.
The plasma generator is arranged in the magnetron sputtering coating cavity, and the emission surface of the plasma generator points to the central position of the magnetron sputtering substrate frame; the included angle alpha between the connecting line of the central point of the emitting surface and the central point of the substrate frame and the axis of the substrate frame is distributed between 30 and 60 degrees, and the height H between the horizontal plane of the central point of the emitting surface and the horizontal plane of the substrate frame is distributed between 10 and 30 cm.
The invention is suitable for MgO and Al2O3、SiO2And performing densification plating on the secondary electron emission thin film layer. In the coating process, the setting range of deposition air pressure is 0.5-2mTorr, the setting range of coating power of the secondary electron emission film is 120-200W, the plasma generator is synchronously started, the power of the plasma generator is 50-150W, and the parameters can ensure that the deposition rate of the film is greater than that of the film
Figure BDA0003433500900000041
Realizing the densification preparation of the secondary electron emission film.
The density of the secondary electron emission thin film layer prepared by the method can be obviously improved, the ion and electron bombardment resistance can be obviously improved, and the attenuation rate index of the electron multiplier can be reduced to be below 0.2V/day.
Example 1
Taking the MgO-densified plating of the secondary electron emission thin film layer as an example, the following will be explained:
the plasma generator is arranged in the magnetron sputtering coating cavity, and the emission surface of the plasma generator points to the central position of the magnetron sputtering substrate frame; the included angle alpha between the connecting line of the central point of the emitting surface and the central point of the substrate frame and the axis of the substrate frame is 50 degrees, and the height H of the horizontal plane of the central point of the emitting surface from the horizontal plane of the substrate frame is distributed at 20 cm. Preparing MgO by adopting a plasma-assisted magnetron sputtering mode, wherein the deposition pressure is 1mTorr, and the deposition power is 200W; and synchronously starting the Hall type ion source at the end part, wherein the power of the ion source is 60W, the discharge voltage is 60V, the discharge current is 1A, the ion energy is distributed at 60eV, and the divergence angle of the ion beam is 30-70 degrees. FIG. 4 is the comparative data of X-ray energy spectrum analysis of MgO film prepared by plasma-assisted magnetron sputtering technique and conventional magnetron sputtering technique, and it is apparent from the figure that the characteristic peak of the MgO film [111] prepared by plasma-assisted magnetron sputtering technique is significantly enhanced. FIG. 5 is a graph showing the attenuation curve of an electron multiplier assembled from MgO thin films prepared by plasma-assisted magnetron sputtering, from which it can be seen that the attenuation rate is 0.2V/day.
In summary, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (5)

1.一种二次电子发射薄膜致密化成膜方法，其特征在于，在磁控溅射镀膜腔室中安装等离子体发生器；在磁控溅射镀膜过程中同步开启等离子体发生器，等离子体发生器产生等离子体，起到增加成膜粒子能量、剥蚀大尺寸颗粒、增强膜层的致密性与附着力的作用。1. a secondary electron emission film densification film-forming method is characterized in that, plasma generator is installed in magnetron sputtering coating chamber; The plasma generator generates plasma, which increases the energy of film-forming particles, erodes large-sized particles, and enhances the compactness and adhesion of the film. 2.如权利要求1所述的二次电子发射薄膜致密化成膜方法，其特征在于，所述等离子体发生器为端部霍尔型离子源；端部霍尔型离子源的放电电压50～300V，放电电流1～15A，离子能量分布于10～140eV，离子束流发散角25°～75°。2. The method for densifying and forming a secondary electron emission film according to claim 1, wherein the plasma generator is an end Hall type ion source; the discharge voltage of the end Hall type ion source is 50 ～300V, discharge current 1～15A, ion energy distribution in 10～140eV, ion beam divergence angle 25°～75°. 3.如权利要求1或2所述的二次电子发射薄膜致密化成膜方法，其特征在于，等离子体发生器安装于磁控溅射镀膜腔室中，等离子体发生器的发射面指向磁控溅射基片架中心位置；所述发射面中心点与基片架中心点的连线，与基片架轴线呈夹角α，所述α为30°～60°；所述发射面中心点水平面距离基片架水平面高度H，所述H为10-30cm。3. The method for densification and film formation of secondary electron emission thin films as claimed in claim 1 or 2, wherein the plasma generator is installed in a magnetron sputtering coating chamber, and the emission surface of the plasma generator points to the magnetic field. The center position of the sputtering substrate holder is controlled; the connection line between the center point of the emitting surface and the center point of the substrate holder forms an angle α with the axis of the substrate holder, and the α is 30° to 60°; the center of the emitting surface The height H between the horizontal plane of the point and the horizontal plane of the substrate holder is 10-30 cm. 4.如权利要求1所述的二次电子发射薄膜致密化成膜方法，其特征在于，所述二次电子发射薄膜为MgO、Al2O3或SiO2薄膜。4 . The method for densifying and forming a secondary electron emission film according to claim 1 , wherein the secondary electron emission film is a MgO, Al 2 O 3 or SiO 2 film. 5 . 5.如权利要求1所述的二次电子发射薄膜致密化成膜方法，其特征在于，镀膜过程中，镀膜气压为1～2mTorr，磁控溅射的功率为120～200W，同步开启等离子体发生器，等离子体发生器功率为50～150W，膜层沉积速率大于
Figure FDA0003433500890000011
5. The method for densification and film formation of a secondary electron emission film according to claim 1, characterized in that, during the coating process, the coating pressure is 1-2 mTorr, the power of the magnetron sputtering is 120-200 W, and the plasma is turned on synchronously. generator, the power of the plasma generator is 50-150W, and the film deposition rate is greater than
Figure FDA0003433500890000011
CN202111602863.2A 2021-12-24 2021-12-24 Densification film forming method for secondary electron emission thin film Pending CN114438462A (en)

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Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6386864A (en) * 1986-09-29 1988-04-18 Nippon Telegr & Teleph Corp <Ntt> Ion source
US6214183B1 (en) * 1999-01-30 2001-04-10 Advanced Ion Technology, Inc. Combined ion-source and target-sputtering magnetron and a method for sputtering conductive and nonconductive materials
CN1870229A (en) * 2005-05-25 2006-11-29 宗祥福 Cu/Ta/Si base substrat structure for integrated circuit and its manufacturing method
CN101285167A (en) * 2008-06-03 2008-10-15 西安工业大学 Ion beam emission source capable of outputting single ion energy
CN102308358A (en) * 2008-12-08 2012-01-04 通用等离子公司 Closed drift magnetic field ion source device with self-cleaning anode and substrate modification modification method
CN103243305A (en) * 2013-04-22 2013-08-14 兰州空间技术物理研究所 Secondary electron emission film preparation method
CN104561900A (en) * 2014-12-16 2015-04-29 兰州空间技术物理研究所 Method for preparing low-absorption rate silicon oxide film
CN112329247A (en) * 2020-11-11 2021-02-05 成都理工大学工程技术学院 Simulation method for discharge plasma and self-sputtering of Hall electric thruster
CN112899630A (en) * 2021-01-19 2021-06-04 佛山市博顿光电科技有限公司 Coating equipment and coating control method thereof

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6386864A (en) * 1986-09-29 1988-04-18 Nippon Telegr & Teleph Corp <Ntt> Ion source
US6214183B1 (en) * 1999-01-30 2001-04-10 Advanced Ion Technology, Inc. Combined ion-source and target-sputtering magnetron and a method for sputtering conductive and nonconductive materials
CN1870229A (en) * 2005-05-25 2006-11-29 宗祥福 Cu/Ta/Si base substrat structure for integrated circuit and its manufacturing method
CN101285167A (en) * 2008-06-03 2008-10-15 西安工业大学 Ion beam emission source capable of outputting single ion energy
CN102308358A (en) * 2008-12-08 2012-01-04 通用等离子公司 Closed drift magnetic field ion source device with self-cleaning anode and substrate modification modification method
CN103243305A (en) * 2013-04-22 2013-08-14 兰州空间技术物理研究所 Secondary electron emission film preparation method
CN104561900A (en) * 2014-12-16 2015-04-29 兰州空间技术物理研究所 Method for preparing low-absorption rate silicon oxide film
CN112329247A (en) * 2020-11-11 2021-02-05 成都理工大学工程技术学院 Simulation method for discharge plasma and self-sputtering of Hall electric thruster
CN112899630A (en) * 2021-01-19 2021-06-04 佛山市博顿光电科技有限公司 Coating equipment and coating control method thereof

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Application publication date: 20220506