CN201102984Y - Synchronous measurement device for ion beam current density and energy - Google Patents

Abstract

A synchronous measuring device for ion beam current density and energy of an ion source, a cylindrical collection tube made of magnetic shielding material, an ion filter arranged in the cylindrical collection tube, a drainage hole arranged on the side wall of the collection tube and at the connection between the semicircular and triangular hypotenuses of the ion filter by using magnetic shielding material, a bowl-shaped electron receiver arranged at the semicircular position of the ion filter, a sheet-shaped cation receiver arranged at the right angle and hypotenuse positions of the isosceles right triangle of the ion filter, the ion filter is grounded and insulated from the cation receiver and the electron receiver, electromagnetic coils are arranged at the two end surfaces in the collection tube, the two electromagnetic coils are connected to an adjustable constant voltage DC power supply outside the collection tube, the cation receiver is grounded via a first resistor and a first milliammeter, and the electron receiver is grounded via a second resistor and a second milliammeter. The utility model device is simple to use, easy to operate, and highly practical.

Description

Synchronous measurement device for ion beam current density and energy

technical field

The utility model relates to an ion-assisted deposition coating technology, in particular to a synchronous measuring device for ion beam current density and energy of an ion source, and can also be used for ion implantation, modification, and ion energy and beam current emitted by an ion source in sputtering Measurement of density.

Background technique

Ion beam technology has been proven to effectively improve the quality of thin films and is widely used in thin film deposition technology. The performance of its key equipment, the ion source, has also become an important factor affecting the deposition quality.

The ion source emits an ion beam with a certain ion energy and beam current density, which makes it travel a certain distance in the vacuum chamber and then acts on the film molecules or atoms to exchange momentum and energy, thereby changing the properties of the growing film, which is The process of ion-assisted deposition.

The advantage of ion-assisted deposition is that the properties of the film can be controlled by controlling the parameters of the ions. Therefore, to investigate the ion beam-assisted effect, the parameters of the ion beam must be investigated, including the ion beam current density, energy, ion beam divergence angle, ion species, etc. , where ion energy and beam current density are the most important and most difficult parameters to determine, so ion beam assisted deposition requires a device to detect ion beam current density and energy.

The simultaneous measurement of ion beam current density and energy has the following difficulties:

Separation of cations and electrons. The ion beam emitted by the ion source is generally a plasma in which cations and electrons co-exist, and the mutual interference between them affects the accuracy of the measurement, so it needs to be separated during detection.

Synchronization of beam density and energy measurements. It is very impractical to measure the spatial distribution and energy distribution of the same ion, so the two parameters need to be measured for two kinds of particles.

Contents of the invention

The technical problem to be solved by the utility model is to overcome the above difficulties and provide a synchronous measuring device for the ion beam current density and energy of the ion source. The device should have the characteristics of simple structure and convenient operation.

The technical solution of the utility model is as follows:

A synchronous measurement device for ion beam current density and energy of an ion source, characterized in that it includes: a cylindrical collection tube made of magnetic shielding material, and a cylindrical ion filter is arranged in the cylindrical collection tube , its cross-section is enclosed by a semicircle and the right side and the hypotenuse of an isosceles right triangle, on the side wall of the collection tube and the semicircle of the ion filter and the hypotenuse of the triangle are connected Use magnetic shielding material to set a drainage hole, set a bowl-shaped electronic receiver at the semicircular position of the ion filter, and set a sheet-like cation receiver at the right-angled side and hypotenuse of the isosceles right-angled triangle of the ion filter , the ion filter is grounded, but is insulated from the positive ion receiver and the electronic receiver. Electromagnetic coils are respectively arranged on the two end faces of the collection tube, and the two electromagnetic coils are connected to an adjustable constant voltage DC outside the collection tube. The power supply is connected to establish a constant adjustable uniform magnetic field in the ion filter in the collection tube. The positive ion receiver is grounded through the first resistor and the first milliampere meter, and the electronic receiver is grounded through the second resistor. and the second mA meter to ground.

The size of the metal sheet of the cation receiver is equivalent to the size of the drainage hole, and they are respectively placed symmetrically on both sides of the hypotenuse of the ion filter and perpendicular to each other.

The centers of the two electromagnetic coils are coaxial, and the distance between them is equal to the diameter of the coils.

Advantages of the utility model

The utility model can simultaneously measure ion energy and beam current density. The distribution law of beam current density and ion energy can be obtained at the same time. The device can not only be used for measuring ion beam current density and energy in ion-assisted deposition, but also can be used for measuring beam current density and energy in ion implantation, ion modification and ion sputtering. The device of the utility model is simple to use, convenient to operate and strong in practicability.

Description of drawings

Fig. 1 is the structural sectional schematic diagram of the synchronous measuring device of ion energy and beam current density of ion source of the present invention

Fig. 2 is the relationship curve between relative beam current and ion energy of Ar ion measured by the utility model. The relationship curve between Ar ion relative beam current and ion energy when the anode voltage of the ion source is 120V represents the distribution of ion energy, and the abscissa at the center line represents the average energy of the ion beam.

Fig. 3 is the distribution of beam current density when the anode voltage of the ion source is measured at 120V by using the utility model

Fig. 4 is the variation curve of ion average energy measured with the anode voltage by using the utility model.

Detailed ways

Below in conjunction with embodiment and accompanying drawing, the utility model will be further described, but should not limit the protection scope of the utility model with this.

Please refer to Fig. 1, Fig. 1 is the structural sectional view schematic diagram of the ion energy of the ion source of the present invention and the synchronous measuring device of beam current density, as seen from the figure, the synchronous measuring device of ion beam current density and energy of the present utility model is characterized in that Including: a cylindrical collection tube 2 made of magnetic shielding material, a cylindrical ion filter 4 is set in the cylindrical collection tube 2, the cross section of which is a semicircle and a right angle side of an isosceles right triangle and Enclosed by the hypotenuse, on the side wall of the collection tube 2 and the semicircular and triangular hypotenuse joints of the ion filter 4, a magnetic shielding material is used to establish a drainage hole 1, and the ion filter 4 A bowl-shaped electronic receiver 7 is set in the semicircular position of the ion filter 4, and a sheet-shaped positive ion receiver 6 is set at the right angle side and the hypotenuse position of the isosceles right triangle of the ion filter 4, and the ion filter 4 is grounded, but it is connected to the ion filter 4. The positive ion receiver and the electronic receiver are insulated, two end faces of the collection tube 2 are respectively provided with electromagnetic coils 5, and the two electromagnetic coils 5 are connected with an adjustable constant voltage DC power supply outside the collection tube 2, so as to A constant adjustable uniform magnetic field 3 is set up in the ion filter 4 in the collection tube 2, said positive ion receiver 6 is grounded through the first resistance 8 and the first milliampere meter 9, and said electronic receiver 7 is grounded through the first resistor 8. The second resistor 9 and the second mA meter 11 are grounded.

The main performance parameters and the effect of the elements of each part in the present embodiment:

Drainage hole 1: a small hole with a diameter of 2mm located below the device, the hole wall is made of magnetic shielding material, and is used to introduce ion flow.

Collection tube 2: It is a cylindrical closed device, and its shell is made of magnetic shielding material, which is used to avoid the interference of the magnetic field on the ion beam and ensure normal measurement.

Magnetic field 3: Generated by the electromagnetic coils on the front and rear sides of the device, it is used to change the direction of particle movement, so that positive ions and electrons move to the left and right directions respectively, and are captured by the receiver after separation.

Ion filter 4: Surrounded by metal sheets, it completely surrounds the cation receiver, electron receiver and all incident particles. The device is connected to ground to filter out unwanted cations.

Electromagnetic coil 5: Helmholtz coils are composed of electromagnetic coils on the front and rear sides of the device, connected to an external DC power supply, and an adjustable and constant uniform magnetic field 3 is generated by adjusting the power supply voltage.

The cation receiver 6 is made of a metal sheet with a diameter of 2mm, insulated from the shell of the ion filter 4, connected with a first resistor 8 and a first milliampere meter 9 to collect cations with a certain trajectory.

The electronic receiver 7 is a bowl-shaped sheet metal, which can cover the right half of the device and is insulated from the shell of the ion filter. The electronic receiver 7 is grounded through the second resistance 10 and the second milliampere meter 11 to collect the isolated most electronics.

The first resistor 8 is used for voltage division during measurement, and plays a role of protecting the circuit.

The first milliampere meter 9 obtains the quantity of cations flowing through by measuring the current in the circuit.

The second resistor 10: used for dividing voltage during measurement, and protecting the circuit.

The second milliampere meter 11, by measuring the current in the circuit, obtains the electron quantity flowing through.

The measurement process of the utility model device is:

The drainage hole 1 of the device of the present invention is facing the ion emission direction of the ion source to be measured. After the plasma beam emitted by the ion source is incident on the drainage hole 1, under the action of the magnetic field 3, the plasma beam in the collection tube 2 Positive ions and electrons respectively obtain two opposite speeds of motion, as shown in Figure 1, electrons are captured by electron receiver 7 to the right, and electrons flow through second resistance 10 and second milliampere meter 11, by the second milliampere Table 11 records the size of the electron current. Dividing the reading shown in the second mA table 11 by the cross-sectional area of the incident drainage hole 1 is the electron current density. Since what is emitted is plasma, the electron current density is the ion current density. The beam density of the source; while the positive ions move to the left, a part of which is filtered out by the ion filter 4, and only positive ions that meet a certain radius of the orbit can be captured by the positive ion receiver 6. Through the analysis of the trajectory, this condition can be obtained energy of the ions. What the first milliampere table 9 represents is the cation current density at this energy, and we define the comparison of the two representations as the relative beam current, that is, the distribution probability of the beam current at this energy.

Suppose the mass m of the incident ion, the velocity v, the energy E, the electric quantity q, the trajectory radius r, and the magnetic induction intensity B of the variable magnetic field, according to the formula

$\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; mv</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; wxya</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; E.</span>}}{\mathrm{<span\; class="notranslate">\; wxya</span>}}$

The incident ion energy can be calculated. Adjust the magnetic field 3 so that the indication of the first milliampere meter 9 can capture the entire energy range through the process of changing from small to large and then decreasing again. Finally, we can obtain the energy of the ion source by integrating.

The ion source was measured by using the device of the utility model, and the results are shown in Fig. 2, Fig. 3 and Fig. 4 . Tests show that the utility model has the advantages of being able to simultaneously measure ion energy and beam current density. The distribution law of ion beam current density and energy can be obtained simultaneously. The utility model can not only be used for measuring ion beam current density and energy in ion-assisted deposition, but also can be used for measuring beam current density and energy in ion implantation, ion modification and ion sputtering. The device of the utility model is simple to use, convenient to operate and strong in practicability.

Claims (3)

1. A synchronous measurement device for ion beam current density and energy of an ion source, characterized in that it comprises: a cylindrical collection tube (2) is made of a magnetic shielding material, and is arranged in the cylindrical collection tube (2) The ion filter (4) of a cylindrical structure, its cross-section is semicircle and the right angle side of an isosceles right triangle and the hypotenuse enclosing form, on the side wall of this collecting tube (2) and described The semicircle of the ion filter (4) and the hypotenuse junction of the triangle adopt a magnetic shielding material to establish a drainage hole (1), and a bowl-shaped electronic receiver (7) is set at the semicircle position of the ion filter (4) ), the right-angled side and the hypotenuse position of the isosceles right-angled triangle of the ion filter (4) are provided with a sheet-like cation acceptor (6), the ion filter (4) is grounded, but with the described cation acceptor Insulated from the electronic receiver, electromagnetic coils (5) are respectively arranged on the two end faces of the collecting tube (2), and the electromagnetic coils (5) are connected with an adjustable constant-voltage DC power supply outside the collecting tube (2), so as to A constant adjustable uniform magnetic field (3) is set up in the ion filter (4) in this collection tube (2), and said positive ion receiver (6) passes through the first resistance (8) and the first milliampere meter (9) grounding, said electronic receiver (7) is grounded through the second resistor (9) and the second milliampere meter (11). 2. The device for synchronously measuring ion beam current density and energy according to claim 1, characterized in that the size of the metal sheet of the positive ion receiver (6) is equivalent to the size of the drainage hole (1), They are placed symmetrically on both sides of the hypotenuse of the ion filter (4), and are perpendicular to each other. 3. The device for synchronously measuring ion beam current density and energy according to claim 1, characterized in that the centers of the two electromagnetic coils (5) are coaxial, and the distance between them is equal to the diameter of the coils.

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