Method for improving microchannel roughness of microchannel plate

Abstract

The invention provides a method for improving micro-channel roughness of a micro-channel plate, which comprises the following steps of: (1) placing the micro-channel plate in an etching chamber of an ion beam etching system, and fixing the micro-channel plate by using an objective table; (2) the angle of an objective table is adjusted, so that the included angle between the surface normal of the micro-channel plate and the ion beam is 85-89 degrees; and (3) bombarding the micro-channel plate on the objective table through the ion beam current to obtain the micro-channel plate with improved micro-channel roughness. According to the method, the roughness of the surface of the micro-channel plate can be reduced, the roughness of the micro-channel wall of the micro-channel plate can be improved, and a very good effect can be achieved on the roughness of the front type and the roughness of the hill type.

Description

Technical Field

[0001] The present invention belongs to the field of optoelectronics and micro-electromechanical systems. Specifically, the present invention relates to a method for improving the roughness of a microchannel of a microchannel plate. Background Art

[0002] A microchannel plate (MCP) is a micro-hollow channel glass fiber plate with good secondary electron emission performance on the inner wall of the channel. It is a thin plate composed of millions of closely arranged hollow channel tubes and is widely used in low-light image intensifiers, photon detectors, photomultiplier tubes, and space particle detection. Its working principle is that when particles bombard the inner wall of the microchannel plate, secondary electrons will be generated. The secondary electrons are accelerated by the voltage applied at both ends of the microchannel plate and bombard the inner wall of the microchannel plate again, thereby forming more secondary electrons. This process is repeated many times in the microchannel plate, forming a large number of multiplied electrons at its outlet. In this way, each channel is a photomultiplier tube, which can obtain a current gain of tens of thousands of times, and the entire microchannel plate can turn the low-light image into a high-brightness, high-definition image.

[0003] The roughness of the microchannel plate will affect the performance and effect. The sidewalls of the microchannel plate channel are coated with secondary electron emission materials. The rough surface will increase the scattering of electrons during transmission, thereby reducing the efficiency of electron multiplication. The rough surface increases the loss of electrons during transmission, resulting in a degradation of the signal amplification effect. The rough surface causes the device to generate more heat and particles during operation, affecting the stability and reliability of the device.

[0004] At present, the improvement of the roughness of the microchannel wall of the microchannel plate adopts wet technology. It is difficult to accurately control the wet technology. Although it is excellent in reducing the roughness of the "sharp type", it is not effective in reducing the roughness of the "hilly type". The improvement effect is related to the principle of the method. The wet method is a chemical reaction. The chemical reaction time of the "sharp" top of the "sharp" roughness is short. At the same time, the chemical reaction time of the microchannel surface of the microchannel plate is long. The larger reaction time can achieve roughness reduction. The difference between the chemical reaction time of the top of the "hilly" roughness and the chemical reaction time of the microchannel surface is small, and the roughness improvement effect is not good.

[0005] Therefore, there is an urgent need for a method that can achieve good improvement effects on both "sharp-type" and "hilly-type" roughness. Summary of the invention

[0006] The purpose of the present invention is to overcome the defects of the prior art and provide a method for improving the roughness of the microchannel of a microchannel plate. The method can reduce the roughness of the surface of the microchannel plate and improve the roughness of the microchannel wall of the microchannel plate, and can show good effects on both "sharp-edge" and "hilly" roughness.

[0007] The above-mentioned object of the present invention is achieved through the following technical solutions.

[0008] The present invention provides a method for improving the roughness of a microchannel of a microchannel plate, comprising the following steps:

[0009] (1) placing the microchannel plate in an etching chamber of an ion beam etching system and fixing it using a stage;

[0010] (2) adjusting the angle of the stage so that the angle between the surface normal of the microchannel plate and the ion beam is 85°-89°;

[0011] (3) The microchannel plate on the stage is bombarded by an ion beam to obtain a microchannel plate with improved microchannel roughness.

[0012] Preferably, in the method described in the present invention, the method also includes the following steps: applying a voltage of 150-300V to the cathode of the ion source, applying a voltage of 80-140V to the screen grid and applying a voltage of 80-120V to the acceleration grid, and providing an ion beam current of 0.03-0.12A.

[0013] In a specific embodiment of the present invention, the present invention provides a method for improving the microchannel roughness of a microchannel plate, comprising the following steps:

[0014] (1) placing the microchannel plate in an etching chamber of an ion beam etching system and fixing it using a stage;

[0015] (2) adjusting the angle of the stage so that the angle between the surface normal of the microchannel plate and the ion beam is 85°-89°;

[0016] (3) applying a voltage of 150-300 V to the cathode of the ion source, a voltage of 80-140 V to the screen grid, and a voltage of 80-120 V to the acceleration grid, and providing an ion beam current of 0.03-0.12 A;

[0017] (4) The microchannel plate on the stage is bombarded by the ion beam to obtain a microchannel plate with improved microchannel roughness.

[0018] The inventors of the present application unexpectedly found that when the ion beam polishing technology is combined with the microchannel plate, the roughness of the microchannel of the microchannel plate can be improved very well by controlling the polishing parameters. Specifically, the method of the present invention can reduce the roughness of the microchannel surface of the microchannel plate and improve the roughness of the microchannel wall of the microchannel plate, and can show good effects on both "sharp-edge" and "hilly" roughness.

[0019] In the present invention, if the angle between the surface normal of the microchannel plate and the ion beam is less than 85°, the etching effect will be greater than the polishing effect due to the angle being too small; if the angle between the surface normal of the microchannel plate and the ion beam is greater than 89°, the microchannel polishing will fail due to the angle being too large.

[0020] In the present invention, if a voltage less than 150V is applied to the cathode of the ion source, the cathode voltage is too small, which will result in poor improvement effect on the "sharp type" roughness; if a voltage greater than 300V is applied to the cathode of the ion source, the cathode voltage is too large, which will result in poor improvement effect on the "hill type" roughness.

[0021] In the present invention, if the ion beam current is less than 0.03A, the “edge-type” roughness improvement effect will be poor due to the ion beam current being too small; if the ion beam current is greater than 0.12A, the “hill-type” roughness improvement effect will be poor due to the ion beam current being too large.

[0022] Preferably, in the method described in the present invention, the ion beam current is 0.1A.

[0023] Preferably, in the method described in the present invention, a voltage of 200 V is applied to the cathode of the ion source, a voltage of 120 V is applied to the screen grid, and a voltage of 100 V is applied to the acceleration grid.

[0024] Preferably, in the method of the present invention, the ion beam is composed of argon ions.

[0025] Preferably, in the method described in the present invention, the flow rate of the ion beam is set to 5-24 sccm.

[0026] Preferably, in the method of the present invention, the bombardment in step (3) is carried out for 20-35 minutes.

[0027] Preferably, in the method described in the present invention, the bombardment in step (3) is carried out for 30 minutes.

[0028] The method of the present invention can be implemented by means of an ion beam etching system (1). Specifically, the ion beam etching system may include:

[0029] A stage system (2) for carrying the microchannel plate;

[0030] a baffle (3) for blocking the unstable ion beam from acting on the microchannel plate;

[0031] A chamber (4) which provides a vacuum space for the ion beam and the microchannel plate to interact;

[0032] An ion source (5) for realizing an ion beam for improving the roughness of a microchannel of a microchannel plate;

[0033] a cathode (6) for realizing electrons that collide with gas molecules;

[0034] A screen grid (7) for shaping a large number of gas ions into an ion beam;

[0035] an accelerating grid (8) for accelerating ions of the ion beam;

[0036] an ion beam (9) for interacting with a microchannel plate;

[0037] a gas inlet (10) for providing a gas of ionic species;

[0038] A microchannel plate (11) is used to provide microchannels for interaction with ion beams.

[0039] The present invention has the following beneficial effects:

[0040] The method of the present invention can reduce the roughness of the microchannel surface of the microchannel plate and improve the roughness of the microchannel wall of the microchannel plate, and can show the effect of reducing the roughness from hundreds of nanometers to several nanometers for both "sharp edge" and "hill type" roughness. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The embodiments of the present invention are described in detail below with reference to the accompanying drawings, wherein:

[0042] Figure 1 A schematic diagram of improving the roughness of a microchannel of a microchannel plate by means of an ion beam etching system provided for a specific embodiment of the present invention;

[0043] Figure 2 A schematic diagram of the interaction between an ion beam and a microchannel of an ion beam polishing microchannel plate provided for a specific embodiment of the present invention;

[0044] Figure 3 The electron microscope image of the microchannel plate A with sharp roughness before the roughness is improved by using Example 1 of the present invention;

[0045] Figure 4 The electron microscope image of the microchannel plate A after the roughness is improved by using Example 1 of the present invention;

[0046] Figure 5 The electron microscope image of the microchannel plate B with hilly roughness before the roughness is improved by using Example 2 of the present invention;

[0047] Figure 6 The electron microscope image of the microchannel plate B after the roughness is improved by using Example 2 of the present invention;

[0048] Description of reference numerals:

[0049] 1: Ion beam etching system;

[0050] 2: Stage system;

[0051] 3: baffle;

[0052] 4: Chamber;

[0053] 5: ion source;

[0054] 6: cathode;

[0055] 7: Screen grid;

[0056] 8: Acceleration gate;

[0057] 9: ion beam;

[0058] 10: Air inlet;

[0059] 11: microchannel plate;

[0060] 2-1: microchannel wall;

[0061] 2-2 and 2-3: Ion beam. DETAILED DESCRIPTION

[0062] The present invention is further described in detail below in conjunction with specific embodiments. The given examples are only for illustrating the present invention, but not for limiting the scope of the present invention.

[0063] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail by specific embodiments below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0064] Example 1

[0065] The present invention provides a method for improving the roughness of a microchannel of a microchannel plate. The present invention is described in detail below in conjunction with the accompanying drawings. Figure 1 and Figure 2 . Figure 1 A schematic diagram of improving the microchannel roughness of a microchannel plate by means of an ion beam etching system according to an embodiment of the present invention. To improve the microchannel roughness of the microchannel plate, argon gas needs to be introduced through the air inlet (10), and the flow rate is set to 24 sccm. In the space provided by the chamber (4), a voltage of 200V is applied to the cathode (6) of the ion source, a voltage of 120V is applied to the screen grid (7), and a voltage of 100V is applied to the acceleration grid (8) to form an ion beam current of 0.1A. The stage system (2) carries the microchannel plate (11) and realizes that the surface normal of the microchannel plate (11) and the ion beam have an angle of 85°. The baffle (3) blocks the unstable ion beam from interacting with the microchannel plate (11). After 30 minutes, the improvement of the roughness of the microchannel surface and the microchannel wall of the microchannel plate is achieved.

[0066] Figure 2 The present invention provides a schematic diagram of the interaction between the ion beam and the microchannel of the ion beam polishing microchannel plate provided by the present invention. The ion beam (2-2) interacts with the microchannel wall (2-1) of the microchannel plate, and the ion beam (2-3) interacts with the surface of the microchannel plate. After a certain period of time, the microchannel surface and sidewall of the microchannel plate are ion-polished.

[0067] Figure 3 This is an electron microscope image of a microchannel plate A with an edgy roughness before the roughness is improved by using Example 1 of the present invention. The microchannel plate A with an edgy roughness is obtained by referring to the preparation method of the microchannel disclosed in the prior art CN 202311332344.8.

[0068] Figure 4 This is an electron microscope image of a microchannel plate A after the roughness is improved by using Example 1 of the present invention; this image shows that the roughness of the microchannel plate can be significantly improved by using the method of the present invention.

[0069] Example 2

[0070] The present invention provides a method for improving the roughness of a microchannel of a microchannel plate. The present invention is described in detail below in conjunction with the accompanying drawings. Figure 1 and Figure 2 . Figure 1 A schematic diagram of improving the microchannel roughness of a microchannel plate by means of an ion beam etching system according to an embodiment of the present invention. To improve the microchannel roughness of the microchannel plate, argon gas needs to be introduced through the air inlet (10), and the flow rate is set to 24 sccm. In the space provided by the chamber (4), a voltage of 400V is applied to the cathode (6) of the ion source, a voltage of 120V is applied to the screen grid (7), and a voltage of 100V is applied to the acceleration grid (8) to form an ion beam current of 0.1A. The stage system (2) carries the microchannel plate (11) and realizes that the surface normal of the microchannel plate (11) and the ion beam have an angle of 85°. The baffle (3) blocks the unstable ion beam from interacting with the microchannel plate (11). After 30 minutes, the improvement of the roughness of the microchannel surface and the microchannel wall of the microchannel plate is achieved.

[0071] Figure 5 This is an electron microscope image of a microchannel plate B with hilly roughness before the roughness is improved by using Example 2 of the present invention. The microchannel plate B with hilly roughness is obtained by referring to the preparation method of the microchannel disclosed in the prior art CN 202311332344.8.

[0072] Figure 6 This is an electron microscope image of microchannel plate B after the roughness is improved by using Example 2 of the present invention; this image shows that the roughness of the microchannel plate can be significantly improved by using the method of the present invention.

Claims

1. A method for improving the microchannel roughness of a microchannel plate, comprising the following steps: (1) placing the microchannel plate in an etching chamber of an ion beam etching system and fixing it using a stage; (2) adjusting the angle of the stage so that the angle between the surface normal of the microchannel plate and the ion beam is 85°-89°; (3) The microchannel plate on the stage is bombarded by an ion beam to obtain a microchannel plate with improved microchannel roughness.

2. The method according to claim 1, wherein: The method further comprises the following steps: applying a voltage of 150-300V to the cathode of the ion source, applying a voltage of 80-140V to the screen grid and applying a voltage of 80-120V to the acceleration grid, and providing an ion beam current of 0.03-0.12A.

3. The method according to claim 2, wherein: The ion beam current is 0.1A.

4. The method according to claim 2, wherein: A voltage of 200 V was applied to the cathode of the ion source, a voltage of 120 V was applied to the screen grid, and a voltage of 100 V was applied to the acceleration grid.

5. The method according to claim 1, wherein: The ion beam consists of argon ions.

6. The method according to claim 1, wherein: The flow rate of the ion beam is set to 5-24 sccm.

7. The method according to claim 1, wherein: The bombardment in step (3) is carried out for 20-35 minutes.

8. The method according to claim 7, wherein: The bombardment in step (3) was carried out for 30 minutes.

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