JPH07100851B2 - Electron beam heating control method and control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention controls an electron beam so that the electron beam is irradiated to a set position when using the electron beam melting apparatus, the electron beam vapor deposition apparatus, or the like. The present invention relates to an electron beam heating control method and apparatus, in which the electron beam does not deviate from a set position.

[Prior Art] Conventionally, there are electron beam type, high-frequency induction type, direct current type, and the like as heating methods for vacuum vapor deposition apparatuses. Especially, the electron beam type heating method has excellent controllability of heating and uses a water-cooled crucible. It is suitable for melting metals and is widely used.

FIG. 1 shows a typical structure of an electron beam heating type vapor deposition apparatus. An electron beam emitted from an electron beam gun exit port 11 is deflected by a deflection coil 12 in the y and z directions of the electron beam, and enters a vapor deposition material 15 in a water-cooled copper crucible 14 in the trajectory of the electron beam as shown by reference numeral 13. To do. Electromagnets 16 for generating a magnetic field for deflecting the electron beam to the crucible surface are arranged on both sides of the crucible 14.

In order to heat the vapor deposition material with this electron beam, it is necessary to control the electron beam properly to realize a predetermined heating pattern. In the conventional laboratory-scale small vapor deposition equipment, the heating range was small and there was no problem of control, but with the enlargement of the vapor deposition equipment and the widening of the vapor deposition equipment, the electron beam is not sufficiently controlled and the film thickness of the vapor deposition metal is Problems such as unevenness have occurred.

In order to solve these problems, a method of arranging spiral magnets on both sides of a crucible to scan an electron beam, as disclosed in JP-A-1-129963, and JP-A-1-129963
Japanese Patent No. 272762 discloses a method of arranging a coil that generates a uniform magnetic field around the crucible to facilitate scanning with an electron beam. However, it is inherently insufficient to reliably control the electron beam only by these means.

That is, the electron beam is generally controlled by the biaxial deflection coil 12 installed at the electron beam emission port 11. When a certain heating pattern is assumed, it is required to set an appropriate current value in this biaxial deflection coil and accurately control the electron beam.

[Technical problem to be solved by the invention] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a control method capable of correctly injecting an electron beam into a position assumed in advance, Another object of the present invention is to provide a control device capable of switching so as to flow different electron beam control currents during vapor deposition and during ionization.

[Means and Actions for Solving the Problems] That is, according to the heating control method of the present invention, the preset electron is controlled while controlling the vertical deflection angle and the horizontal deflection angle of the electron beam from the electron beam gun for heating the vapor deposition material. A heating control method for an electron beam in which an electron beam is incident on a vapor deposition material based on an incident pattern of the beam, wherein a horizontal vertical deflection angle and a left-right symmetrical swing are set in advance during vapor deposition and during ion plating. The incident position of the electron beam at the direction deflection angle is obtained in advance, and based on this position, the vertical deflection angle is corrected by adding a function system consisting of information on the horizontal deflection angle to the ionization current at the time of incidence of the electron beam. To detect whether it is vapor deposition or ion plating, and correct the vertical deflection angle and horizontal deflection angle during vapor deposition, or This is a heating control method for an electron beam, which controls the electron beam to have a desired incident pattern with the corrected vertical deflection angle and horizontal deflection angle at the time of ion plating.

Further, the first heating control device of the present invention controls the vertical deflection angle and the horizontal deflection angle of the electron beam from the electron beam gun for heating the vapor deposition material while controlling the incident pattern of the preset electron beam. A heating control device for an electron beam for injecting an electron beam into a vapor deposition material based on:
A detector that detects the vaporization or ion plating by detecting the ionization current when the electron beam is incident, and detects the heating stage of ion plating based on the ionization current value, and the upper and lower sides corrected for the vapor deposition and each heating stage. A plurality of voltage generators in which a horizontal deflection angle pattern is input to the direction deflection angle, and among the plurality of voltage generators based on the generation of the pattern, the input to the voltage generator, and the detection signal from the detector A computer that selects a voltage generator with a corresponding pattern, starts and stops the voltage generator, and controls the vertical deflection angle and the horizontal deflection angle of the electron beam based on the output voltage from the voltage generator. And control means.

Further, the second heating control device of the present invention controls the vertical deflection angle and the horizontal deflection angle of the electron beam from the electron beam gun for heating the vapor deposition material while controlling the incident pattern of the preset electron beam. A heating control device for an electron beam for injecting an electron beam into a vapor deposition material based on:
A detector that detects the vaporization or ion plating by detecting the ionization current when the electron beam is incident, and detects the heating stage of ion plating by the ionization current value, and the electron beam based on the detection signal from the detector A computer that detects the deflection current pattern of, corrects the vertical deflection angle based on the detected pattern, and outputs a voltage related to the horizontal deflection angle to the vertical deflection angle,
A heating control device for an electron beam, comprising: a control means for controlling a vertical deflection angle and a horizontal deflection angle of the electron beam based on an output voltage from a computer.

The trajectory of the electron beam from the electron beam gun greatly varies due to the magnetic field generated by the electromagnet 16. In order to accurately grasp these magnetic field distributions, the present inventor performed magnetic field analysis and measurement of the magnetic field distributions. FIG. 2 shows the magnetic flux line distribution obtained by analysis. In the figure, 21 is an electron beam emission port, 22 is an electromagnet yoke, 23 is an electromagnetic coil, 24 is a vapor deposition surface, 25 is a magnetic flux line, and 26 is a magnetic flux density vector. The results of these analyzes were in good agreement with the measured values. Electron beam is magnetic flux density vector
With respect to 26, the velocity component in the vertical direction is deflected. That is, the trajectory of the electron beam in the magnetic field is represented by the equation (1).

m · dv / dt = eV × B Equation (1) where m is the electron mass, t is time, V is the velocity vector,
e is the charge of the electron, B is the magnetic flux density vector, and x is the outer product. FIG. 3 shows the horizontal angle θ when the vertical angle θy of the beam is constant.
The result of calculation of the landing point of the electron beam on the crucible surface when z is changed according to the formula (1) and the result of the experiment are shown. Here, 31 is θy = -12.5 °, -15.0 °, -17.5
°, -20 ° ≤ θz ≤ 20 °, the analysis shows the landing line on the crucible of the beam, and the shaded area 32 is θv =
The experimental results of the landing point where θz is set to -12.5 ° are shown, and both agree well. Note that 33 is the glue in the crucible. From this figure, it can be seen that the landing point of the beam is curved even if the vertical angle is constant. These curvatures are a problem when heating the crucible surface to a rectangle. In order to solve this, it is necessary to give the current vertical angle information to the horizontal scanning and correct it. That is, θy = a + f (t) + I (θz) formula (2) θz = b + g (t) formula (3) where θy is the vertical angle of the electron beam, θz is the horizontal angle of the electron beam, and a and b are offsets. f (t) and g (t) are functions of time, and I (θz) is a correction function of θy. I (θ
The functional form of z) is, for example, the form of C (θz) ⁿ , and is determined from the trajectory of the electron beam on the crucible in FIG. Where C
Is a constant value. The relationship between θy and θz and the deflection current of the electron beam is proportional to each other, and the relational expressions of the expressions (2) and (3) can be directly converted into the deflection current value.

Then, by controlling the vertical deflection angle and the horizontal deflection angle based on the equations (2) and (3), the input position of the electron beam can be controlled with a desired input pattern.

However, during vacuum vapor deposition, when the vapor deposition shifts to ion plating, the trajectory of the electron beam changes due to the generation of a magnetic field associated with the ionization current. Therefore, the deflection coil 12
It is necessary to change the current pattern to be applied to. In this case as well, if the vertical deflection angle and the horizontal deflection angle at the time of ion plating are measured in advance and Equations (2) and (3) at the time of ion plating are obtained, the correct response can be achieved. You can

[Examples] As described above, the method of the present invention was carried out by performing correction by adding a functional form consisting of horizontal angle information to the vertical angle deflection of the electron beam. The results are shown in FIG. On the other hand,
FIG. 5 shows a comparison control method in which I (θz) = 0 in equation (2) and θy and θz are independent. By adding the additional control term of I (θz) to θy in the equation (2) as in the present invention, it becomes possible to control the electron beam linearly.
Then, it becomes possible to control an arbitrary electron beam by controlling using these relational expressions.

As an apparatus capable of properly performing this control method, there is an apparatus shown in FIG. 6, for example. This apparatus is provided with a detector 41 which detects an ionizing current to detect a heating step of vapor deposition or ion plating, and a disk 42 which contains various current patterns in advance. Then, the heating stage detection signal from the detector 41 is input to the computer 43. The voltage pattern corresponding to the current pattern of the heating stage is preset in each voltage generator 44 by the computer 43, and the computer 43 selects the voltage generator 44 corresponding to the detected heating turn. In the voltage generator 44,
The set voltage pattern (θy, θz) is transmitted at a predetermined frequency. Based on this signal, the control means 45 controls the trajectory of the electron beam from the electron beam gun. The control computer 43 has functions of creating, changing, managing voltage patterns, switching and controlling voltage generators, and the like. Reference numeral 46 is an oscilloscope for visually observing the signal from the computer 43.

According to this device, since the plurality of voltage generators 44 that set the voltage value according to the ionization current value are provided, by detecting the current pattern and switching the voltage generator 44 according to the detected value. It is possible to control with a desired heating pattern during vapor deposition or ion plating.

FIG. 7 shows another control device. This apparatus is provided with a detector 51 which detects an ionization current to detect a heating step of vapor deposition or ion plating, and a disk 53 which contains various current patterns in advance. And detector 51
The heating stage detection signal from the computer is input to the computer 52.
The computer 52 searches for a predetermined deflection pattern of the electron beam in the disk 53 based on the heating stage detection signal, and corrects the vertical deflection angle based on the retrieved current pattern. Further, a voltage pattern (θy, θz) corresponding to the detected heating stage is created. The output voltage from the control computer 52 is input to the amplifier 54, where the output voltage is amplified and the vertical angle signal (θy) and the horizontal angle signal (θz) are transmitted at a predetermined frequency. Control means based on this signal
55 controls the trajectory of the electron beam from the electron beam gun. The control computer 52 has functions of creating, changing, managing voltage patterns, switching and controlling voltage amplifiers, and the like. 56 is an oscilloscope.

[Effects of the Invention] As described above, according to the present invention, it is possible to accurately control an electron beam by adding a functional form composed of horizontal angle information to the vertical angle deflection of the electron beam.
Further, it is possible to switch so as to flow different electron beam control currents during vapor deposition and during ionization.

[Brief description of drawings]

FIG. 1 is a diagram showing a typical electron beam vapor deposition apparatus, FIG. 2 is a diagram showing a magnetic field distribution around the crucible obtained by analysis, and FIG. 3 is a trajectory of the electron beam on the crucible obtained by analysis and experiment. FIG. 4, FIG. 4 is a diagram showing an example of a trajectory of an electron beam which is accurately controlled by linear scanning in the present invention, FIG. 5 is a diagram showing a trajectory of an electron beam by a conventional method, and FIGS. 6 and 7 are It is a block diagram showing another example of each of the device of the present invention. 11 ... Electron beam gun exit port, 12 ... Electron beam y and z deflection coils, 13 ... Electron beam trajectory, 14 ... Water-cooled copper crucible, 15 ... Vapor deposition material, 16 ... Electromagnet, 21 ... Electron beam exit port , 22 ... Electromagnetic yoke, 23 ... Electromagnetic coil, 24 ... Deposit surface, 25 ... Magnetic flux line, 26 ... Magnetic flux density vector, 31 ... Beam crucible landing line (analysis value), 32 ... θy = -12.5 ° and θz The landing point (experimental value) that was swung, 33 ... Nori in the crucible,
41 ... Detector, 42 ... Disk, 43 ... Computer, 44 ... Voltage generator, 45 ... Control means, 46 ... Oscilloscope, 51 ... Detector, 52 ... Computer, 53 ... Disk, 54 ... Amplifier,
55 ... Control means, 56 ... Oscilloscope

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Kibe 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Inside Nippon Steel Tube Co., Ltd. (72) Koji Matsui 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Nihon Steel Pipe Co., Ltd. (56) References JP-A-60-8971 (JP, A)

Claims (3)

[Claims] 1. An electron beam as a vapor deposition material based on a preset incident pattern of the electron beam while controlling a vertical deflection angle and a horizontal electron beam deflection angle of an electron beam from an electron beam gun for heating a vapor deposition material. A method for controlling the heating of an incident electron beam, in which the incident position of the electron beam at a constant vertical deflection angle and a horizontal deflection angle which is symmetrically swung in advance during vapor deposition and ion plating is obtained. Then, based on this incident position, the vertical deflection angle is corrected by adding a function system consisting of information on the horizontal deflection angle, and the ionization current at the time of electron beam incidence is detected to detect vapor deposition or ion plating. , Corrected vertical and horizontal deflection angles during vapor deposition, or corrected vertical directions during ion plating In the direction angle and horizontal deflection angle, the heating control method of the electron beam to control so that the electron beam has a desired incidence pattern. 2. An electron beam as a vapor deposition material based on a preset incident pattern of the electron beam while controlling a vertical deflection angle and a horizontal deflection angle of the electron beam from an electron beam gun for heating the vapor deposition material. A heating control device for an incident electron beam, which detects ionization current during electron beam incidence to detect vapor deposition or ion plating, and a heating step of the ion plating based on the ionization current value. , A plurality of voltage generators to which patterns of vertical deflection angle and horizontal deflection angle corrected corresponding to vapor deposition and each heating stage are input, and generation of the pattern and input to the voltage generator and from a detector Select a voltage generator with a corresponding pattern from multiple voltage generators based on the detection signal, start the voltage generator,
An electron beam heating control device comprising: a computer for stopping the operation; and a control means for controlling a vertical deflection angle and a horizontal deflection angle of the electron beam based on an output voltage from a voltage generator. 3. An electron beam as a vapor deposition material based on a preset incident pattern of the electron beam while controlling a vertical deflection angle and a horizontal electron beam deflection angle of an electron beam from an electron beam gun for heating the vapor deposition material. A heating control device for an incident electron beam, which detects ionization current during electron beam incidence to detect vapor deposition or ion plating, and a heating step of the ion plating based on the ionization current value. , Detects the deflection current pattern of the electron beam based on the detection signal from the detector, corrects the vertical deflection angle based on the detected pattern, and outputs the voltage related to the vertical deflection angle and the horizontal deflection angle. The computer and the vertical deflection angle and horizontal deflection angle of the electron beam are controlled based on the output voltage from the computer. Heating control apparatus comprising and control means the electron beam.