JPH04246184A - Method and device for strain-free precision numerically controlled working process by radical reaction - Google Patents

Abstract

PURPOSE:To obtain a strain-free worked surface with high precision without introducing defects or heat-affected layers by numerically controlling the working time in conformity to coordinate data based on the coordinate data on the unworked surface and worked surface. CONSTITUTION:A DC or AC high voltage is impressed on a working electrode 2 arranged in a reaction vessel 1 to generate a high electric field between the electrode 2 and a material S to be worked. A neutral radical based on a gaseous reactant is produced by this electric field, hence the generated volatile substance is vaporized and removed, and working is allowed to proceed. A control signal related to the scanning calculated from the correlational data between the working time previously inputted from a computer 5 and the working quantity is inputted to a driving mechanism 4. The angle of rotation or number of revolutions of a servomotor constituting the driving mechanism 4 is numerically controlled, and the material S is scanned along a specified scanning line and worked into a desired shape. As a result, a desired worked surface is automatically obtained with the accuracy in shape of >= about 0.01mum.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a strain-free precision numerical control processing method and apparatus using radical reactions, and more specifically, it relates to a distortion-free precision numerical control processing method using radical reactions, and more specifically, defects in semiconductors or conductors such as silicon single crystals, or insulators such as glass or ceramics. The present invention relates to a strain-free precision numerical control machining method and an apparatus thereof, which enable highly accurate machining without introducing a thermally altered layer.

0002

[Prior Art] Conventionally, neutral radicals based on a reaction gas generated by an electrode to which a high voltage is applied are supplied to the machined surface of a workpiece, and the neutral radicals undergo a radical reaction with atoms or molecules on the machined surface. By vaporizing and removing the volatile substances generated by The strain-free precision machining method is disclosed in Japanese Patent Application Laid-Open No. 1-125 by the present applicant.
It has already been disclosed as Publication No. 829.

On the other hand, in lathe machining based on conventional machining principles using fine cracks, the coordinates of the target machining surface are numerically input, and based on this, numerical control is used to control the amount of feed of the cutting tool in the direction toward the workpiece. Machine tools are already known.

However, in the strain-free precision numerical control machining method and device using radical reactions, the machining principle is fundamentally different from that of the numerically controlled machine tools, so the control mechanism used in the conventional numerically controlled machine tools is not used. It cannot be applied as is. For example, with conventional numerically controlled machine tools, even if the cutting tool is moved along the target shape after the workpiece has been machined into the desired shape, the workpiece will not be further machined, but the radical reaction In the method of the present invention using
When the machining electrode is moved in the same way, neutral radicals generated by the reaction gas are supplied to the machining surface, thereby progressing machining further than the target shape.

[0005]

[Problem to be Solved by the Invention] In view of the above-mentioned situation, the present invention aims to solve the problem by solving the above-mentioned situation. In order to remove the volatile substances and proceed with the machining, we use the fact that there is a correlation between the machining time and the machining amount by the machining electrode at a certain point on the machining surface, and the pre-machining surface input to the control circuit and the target machining are Set the machining time according to the amount of machining that corresponds to the deviation of the coordinates of the surface, and specifically control the scanning speed numerically according to the amount of machining, or set the stop time according to the amount of machining when scanning in steps. It is an object of the present invention to provide a strain-free precision numerical control processing method and an apparatus therefor by means of a radical reaction, which enables numerically controlled processing with a shape accuracy of 0.01 μm or more.

[0006]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention supplies neutral radicals based on a reaction gas generated by a processing electrode to which a high voltage is applied to a processing surface, and This process vaporizes and removes volatile substances generated by radical reactions between the surface and atoms or molecules on the surface to be machined, and processes according to the coordinate difference based on the coordinate data of the pre-machined surface and the target surface to be machined. We have established a distortion-free precision numerically controlled machining method using radical reactions that are time-controlled numerically.

In addition, in controlling the machining time, the shape of the pre-machined surface is measured before the start of machining, and the coordinate data of the pre-machined surface and the target machining surface are input to the control circuit, and the coordinate difference between the two machining surfaces is calculated. Accordingly, the relative scanning speed of the processing electrode and the workpiece was controlled by a drive mechanism numerically controlled by a control circuit.

[0008] In addition, in controlling the machining time, the shape of the pre-machined surface is measured before the start of machining, the coordinate data of the pre-machined surface and the target machining surface are input to the control circuit, and numerically controlled by the control circuit. It is also possible to scan the machining electrode and the workpiece relatively in a stepwise manner using the drive mechanism, and to control the stopping time according to the coordinate difference between the two machining surfaces.

Furthermore, the shape of the pre-machined surface is measured during machining, the coordinate data of the pre-machined surface and the target machining surface are input to the control circuit, and the control circuit performs numerical control according to the coordinate difference between the two machining surfaces. When scanning the relative scanning speed of the machining electrode and the workpiece in a stepwise manner using the drive mechanism, the stop time is controlled according to the coordinate difference between the two machining surfaces. It is also possible to do so.

[0010] In addition, in order to carry out the above method, there is provided a reaction vessel in which an atmospheric gas containing a reaction gas can be sealed or made to flow under high pressure, a processing electrode arranged in the reaction vessel, and a direct current or alternating current applied to the processing electrode. A power supply that applies a high voltage to generate neutral radicals based on a reaction gas, a drive mechanism that includes a servo motor that can relatively displace one of the processing electrode or the workpiece relative to the other, and before starting processing. Alternatively, a measuring means for measuring the shape of a pre-processed surface of a workpiece during processing, a processing time using the processing electrode, and a volatile substance generated by a radical reaction between neutral radicals and atoms or molecules on the processing surface. Correlation data with the amount of machining that can be removed by vaporization is input, and coordinate data of the pre-machined surface and target machining surface of the workpiece can be input, and the relationship between the workpiece and the machining electrode is determined according to the coordinate difference between them. We constructed a distortion-free precision numerical control processing device using radical reaction, which consists of a control circuit that outputs control signals related to relative scanning to the drive mechanism.

[0011]

[Function] The distortion-free precision numerical control machining method and its device using radical reactions of the present invention, which have the above-mentioned contents, are characterized by the machining time using the machining electrode and the radical reaction between neutral radicals and atoms or molecules constituting the machining surface. Taking advantage of the fact that there is a correlation between the amount of machining that progresses after removing volatile substances, the coordinates of the pre-machined surface and the target machining surface of the workpiece are input into a control circuit that has previously input this correlation data. Then, the optimum machining time at a certain point on the machining surface is calculated from the correlation data according to the machining amount corresponding to the coordinate difference, and based on that, the optimum machining time is calculated by a drive mechanism having a servo motor to which a control signal is input. , the processing is performed by moving the processing electrode and the workpiece relative to each other to obtain the desired processed surface without introducing defects or thermally altered layers.

[0012] In addition, in order to process a certain point on the machining surface in an optimal machining time, the relative scanning speed of the machining electrode and the workpiece is adjusted according to the machining amount corresponding to the coordinate difference between the pre-machining surface and the target machining surface. When scanning is performed numerically or in steps, the stopping time is numerically controlled.

Furthermore, when measuring the shape of the pre-processed surface before starting processing and inputting the coordinate data to the control circuit,
Since the relative scanning speed or stop time of the machining electrode and the workpiece is calculated in advance, coordinate calculations during machining can be reduced.

[0014] When the shape of the pre-processed surface is measured during processing and the coordinate data is input into the control circuit, the optimum scanning speed or stop time is calculated as the processing progresses. It is possible to proceed while correcting the machining errors inside.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be further explained in detail based on embodiments shown in the accompanying drawings.

FIG. 1 shows a conceptual diagram of a strain-free precision numerical control processing device using radical reaction according to the present invention, in which 1 is a reaction vessel, 2 is a processing electrode, 3 is a power source, 4 is a drive mechanism, and 5 is a control device. Each shows a computer as a circuit, and S indicates a workpiece.

In the present invention, a DC or AC high voltage is applied from a power source 3 to a machining electrode 2 disposed in a reaction vessel 1 in which an atmospheric gas containing a reaction gas can be sealed or made to flow, thereby connecting the machining electrode 2 and the workpiece. A high electric field is generated in the machining gap between the objects S, and this electric field generates neutral radicals based on the reaction gas, and a radical reaction between these neutral radicals and the atoms or molecules that constitute the machining surface of the workpiece S causes Processing proceeds by vaporizing and removing the volatile substances generated. The machining electrode 2 attached to the drive mechanism 4 receives a scanning control signal calculated based on correlation data between machining time and machining amount inputted in advance from the computer 5 to the drive mechanism 4. The rotation angle or rotation speed of the servo motor constituting the drive mechanism 4 is numerically controlled and scanned along a predetermined scanning line to process it into the desired shape. Further, although not shown, a measuring means for measuring the shape of the pre-processed surface is provided, and the shape of the workpiece S is measured using the measuring means before the start of processing, or is measured during processing and coordinate data is sent to the computer 5. It is possible to input.

Here, the machining time can be controlled by controlling the scanning speed or, in the case of stepwise scanning, by controlling the stopping time. Moreover, when scanning the processing electrode 2 and the workpiece S relatively, there are cases in which either one is fixed and the other is moved, or both are moved. In this embodiment, an embodiment will be described in which the shape of the pre-machined surface is measured before the start of machining, and the machining electrode 2 is moved based on the coordinate data of the pre-machined surface and the target machining surface, and the scanning speed is controlled.

The shape and structure of the machining electrode 2 should be appropriately adopted depending on the shape of the target surface to be machined, and are roughly divided into electric field concentration type and electric field dispersion type. A typical example of this is shown in which the tip is made thinner and the plasma generated between the tip and the machined surface of the workpiece S is localized, thereby limiting the region where the generated neutral radicals exist. , which allows point machining of complex machining surfaces. Examples of the electric field dispersion type electrode include planar electrodes, which can be used to perform smoothing processing in place of lapping.

Further, the high voltage applied from the power supply 3 to the processing electrode 2 is selected as direct current or alternating current depending on whether the workpiece S is a conductor, a semiconductor, or an insulator, and this alternating current is R
F region is used, and the voltage is set to the minimum necessary to generate neutral radicals based on the reactive gas from the ambient gas containing the reactive gas and inert gas, and excessively high-energy charged particles are generated. This prevents damage to the workpiece S. Here, when the workpiece S is a conductor or a semiconductor, a high DC voltage is applied to the processing electrode 2 and the workpiece S is grounded, and when the workpiece S is a semiconductor or an insulator, the workpiece S is grounded. In this step, a high frequency voltage is applied to the processing electrode 2, and the reaction vessel 1 is grounded.

[0021] The machining speed depends on the type of reaction gas and the workpiece S.
It is necessary to select the optimum reaction gas depending on the material of the workpiece S. For example, the workpiece S
When silicon single crystal or quartz glass is used, SF6 is suitable as the reaction gas. Other reactive gases include CF4 for fluorine-based gases, and Cl2 for chlorine-based gases.
, CCl4, PCl4, etc. Note that this reactive gas is not directly excited by a high electric field, but the high electric field first generates an inert gas plasma that is easy to ionize or excite, and then collisions with the reactive gas generate neutral radicals. be. Here, even if neutral radicals are generated in the same area by inert gas plasma and reactive gas,
It is also possible to first generate a plasma of an inert gas and then transport it to collide with a reactant gas in different regions to generate neutral radicals.

Next, the drive mechanism 4 moves the processing electrode 2
on a stage that can be moved in three dimensions (X, Y
, Z), and each stage is driven by a servo motor via a ball screw. The minimum travel distance (travel distance per motor control signal pulse) and maximum travel speed of each stage are determined by the X-axis (
(direction along the reference plane), 0.16μm, 8mm/s
ec, and 0.5 μm and 0.1 mm/s on the Y axis (direction along the reference plane) and Z axis (direction perpendicular to the reference plane).
ec was used. Each servo motor is driven by command pulses from the computer 5, and a system configuration diagram thereof is shown in FIG. Each stage has a similar drive system, and as shown in the figure, feedback pulses from the rotary encoder ensure a normal drive state at all times.

Furthermore, in scanning during numerical control (NC) machining, as shown in FIG. Repeat the operation of sending it in the opposite direction. At this time, the machined surface is obtained as an accumulation of spot-shaped machining marks indicated by circles in the figure.

In this type of machining method, when numerically controlled machining is performed, the stability of machining speed is very important for machining accuracy, and at the same time, what to select as control variables is an important issue. A processing amount when processing is progressed by vaporizing and removing volatile substances generated by a radical reaction between neutral radicals based on the reaction gas of the present invention and atoms or molecules constituting the processing surface of the workpiece S, Since there is a correlation with scanning speed, this scanning speed is used as a control variable. The amount of processing can be controlled by the scanning speed of each point. This correlation data between the amount of processing and the scanning speed is input into the computer 5 in advance.

The coordinates in the numerically controlled machining system according to the present invention are set as shown in FIG. 4, and the conceptual procedure of machining is shown in FIG.
Shown below. Take the reference plane assumed for the workpiece S as the XY plane,
The Z-axis is taken in the direction perpendicular to this plane. When obtaining a target shape according to the present invention, a procedure is taken in which only the deviation from the previously machined surface shape is machined. As shown in the figure, the pre-processed surface is measured with a specified accuracy in a constant temperature room, and the shape data at each coordinate point (
x, y, Z1) are input into the computer 5. In addition, the numerical data (x, y, Z2) of the shape of the target machining surface is also input into the computer at the same time, and the required machining amount Z1-Z at each point is calculated.
2 is calculated. Correlation data between the processing amount and scanning speed for the workpiece S at that time has already been input into the computer, and based on this value, the scanning speed at each point, which is a control variable, is calculated, and the numerical control CVM (Chemical
al Vaporization Machining
) processing is performed.

Next, software for performing NC machining using NC data calculated from the coordinate difference between the measurement result of the pre-machined surface and the shape to be machined will be briefly described.

A flow chart of this software (NC software) is shown in FIG. 6, and its subroutines are shown in FIGS. N
The C software reads the NC data and then controls each axis according to the data therein. The scanning method described above, in which the machining electrode is reciprocated in the X-axis direction and moved little by little in the Y-axis direction with each turn, is described in this NC data. The machining time required for NC machining at each point is controlled by controlling the scanning speed of the machining electrode during X-axis scanning.

[0028] On the NC data, the scanning speed corresponding to the average machining amount in each divided control section is given as NC data, and this NC software makes the change in the scanning speed between the control sections as gentle as possible. The scanning speed is controlled by the acceleration. With this control method, the machining amount between each control section can be linearly interpolated. In addition, if the scanning speed is suddenly changed without such control, a large acceleration will be applied at that moment, and the vibration generated in the stage at this time will change the distance between the processing electrode and the workpiece. The amount of machining shows an abnormal value at this point. Therefore, it is important to control the scanning speed so that it is continuous. Another point to be noted when performing NC machining is the minimum value of the scanning speed of the machining electrode. When the total amount of machining is large, the amount of machining can be increased by reducing the scanning speed of the machining electrode, but at this time, the step difference between the processed part and the non-processed part caused by one scan in the X-axis direction increases, The distribution state of neutral radicals may change. Therefore, the minimum value of the scanning speed is fixed, and when a large amount of processing is required, the processing area is repeatedly scanned.

Next, the specific operation of the NC software will be described. First, NC data stored in an external storage medium such as a floppy disk is stored in the memory of the computer. NC data consists of a header part and a command data part.The header part has information such as title, processing amount, creation date and time, version number, etc., followed by the command data part which is the data for actually executing NC machining. includes loop commands and each axis control command.

Based on the above data, the computer sequentially reads and executes the command data array from the front as shown in the flowcharts of FIGS. 6 to 8. (1) If the command data indicates a termination instruction, the NC machining is terminated at that point. (2) If the command data is Y-axis or Z-axis movement instruction data, the Y axis can be moved by reading the status of the motor control board installed in the computer's expansion I/O slot.
Confirm that the Z-axis stage is stopped, set all pulses and movement speed on the motor control board, and instruct movement. (3) For X-axis movement instruction data, first calculate the acceleration and speed change position (if there is speed control data for NC machining) and confirm that the X-axis stage is stopped. After that, parameters such as initial speed, acceleration, final speed, deceleration start point, deceleration rate, etc. are given to the control board to start the motor. When the motor starts moving, the computer monitors the position of the X-axis stage using the pulse counter on the X-axis motor control board, and when the previously calculated speed change point is reached, the computer changes the speed and acceleration to the control board. Set it to instruct the speed change. This speed change is repeated until there is no more speed control data. Note that (4) if it is loop start instruction data, the data from the next instruction data to the instruction data immediately before the loop end instruction data is executed a specified number of times.

Next, details of X-axis speed control for NC machining will be described. The function of the motor and controller is to automatically perform a series of operations such as starting acceleration, rotating at a constant speed, and decelerating and stopping. Furthermore, if a speed change instruction is given during constant speed rotation, the speed will be changed at the given acceleration. There is also a function to do this. This function is used to control speed for NC machining. Using the NC software, an acceleration period w (the number of rotational pulses of the motor) was provided between each control section as shown in FIG. 9, and acceleration control was performed so that the scanning speed changed continuously. When I started accelerating and rotated w/2, it was N.
In order to match the speed change point given to the C data, a point w/2 before the speed change point given to the NC data is set as the actual speed change point. In order to keep the acceleration as small as possible, it is necessary to make w as large as possible, but since acceleration is performed within the range of w/2 before and after the speed change point given to the NC data, the next speed In order to avoid overlapping with the acceleration section for the speed change point and to make w the largest, it must be made equal to the shorter of the lengths of the control sections before and after the speed change point. The speed change position and acceleration are determined from the length of each control section and the speed data there by
Calculated each time the axis is scanned.

As described above, an example has been described in which the electric field concentration type machining electrode 2 is scanned and spot-like machining marks are accumulated to be machined into an arbitrary target shape.However, when smoothing the workpiece S This can be carried out using a flat electric field dispersion type machining electrode 2 as shown in FIG. The scanning control of the processing electrode 2 in this case is the same as described above, but the feed step in the Y-axis direction is set large.

Furthermore, as shown in FIG. 11, when using a machining electrode 2 that is electric field concentrated but has a shape that extends in the Y-axis direction, scanning in the Y-axis direction becomes unnecessary, and scanning is performed only in the X-axis direction. By scanning, a wave-shaped processed surface as shown in the figure can be obtained.

The processing electrode 2 described above generates plasma between the processing gap between the tip of the processing electrode 2 and the processing surface of the workpiece S, thereby generating neutral radicals in that region. It is an externally generated type. However, as the machining gap changes, the plasma generation state changes, so plasma is always generated under the same conditions inside the electrode, and neutral radicals are generated and the neutral radicals are supplied to the machining surface to advance machining. Endogeneous forms may be preferred. In addition, when using high frequency to generate plasma,
Depending on the material of the workpiece S, this high frequency may be absorbed and heated, so an internal generation type is suitable. Two examples of internally occurring types are shown below.

FIG. 12 shows an internally generated and electric field concentration type machining electrode 2. This processing electrode 2 consists of an electrode 6 at the center that applies a high voltage and a counter electrode 7 that is grounded around the electrode 6.
The electrode 6 is inserted into a hollow counter electrode 7 via an insulator 8 such as insulator. The counter electrode 7 has a nozzle part 9 formed in a tapered shape at its tip and a jet nozzle 10 at its center. ing. Further, in order to supply an atmospheric gas containing a reaction gas into the interior of the counter electrode 7, a supply pipe 12 which is extendable and bendable is connected to a gas supply hole 11 opened in the side surface of the counter electrode 7 or in the insulator 8.
are connected. When atmospheric gas is supplied into the counter electrode 7 from the supply pipe 12, plasma is generated between the tip of the electrode 6 and the inner surface of the nozzle portion 9 of the counter electrode 7, and neutral radicals are generated. By continuously supplying the atmospheric gas, the atmospheric gas containing neutral radicals is supplied from the ejection port 10 to the machining surface of the workpiece S, and the machining progresses as described above. In order to quickly remove atmospheric gases and volatile substances generated by processing from the processing surface,
A gas recovery section 13 having an open end side is provided around the nozzle section 9 of the counter electrode 7, and a recovery pipe 15 similar to the supply pipe 12 is connected to a gas recovery hole 14 formed in the gas recovery section 13. There is. The processing electrode 2 is formed into a cylindrical shape when performing spot processing, and is formed into a long length with the cross-sectional shape shown in the figure when processing a large area at the same time. It is not limited.

FIG. 13 shows an internally generated electric field dispersion type machining electrode 2. This processing electrode 2 has a flat plate-shaped electrode 6 arranged inside a flat hollow counter electrode 7.
A support rod 16 extending from the electrode 6 is fixed to one side via an insulator 8, and a large number of jetting ports 10, . is forming. The plate-shaped electrode 6 is disposed close to the inner surface of the flat surface 17, and an atmospheric gas containing a reaction gas is supplied through the supply pipe 12 connected to the counter electrode 7 and the gas supply hole 11, so that the electrode 6 and Plasma is generated between the flat surface 17 and neutral radicals, which are supplied from the jet nozzle 10 to the processing surface of the workpiece S. Although not shown, a recovery section similar to the gas recovery section 13 described above is provided as appropriate.

FIG. 14 shows an example of an externally generated and electric field concentration type machining electrode 2, in which an atmospheric gas outlet 10 is formed at the center of the tip of a single tapered electrode, and the outlet 10 is communicated with. A gas supply hole 11 is formed, a supply pipe 12 is connected to the gas supply hole 11, and a gas recovery section 13 is connected in the same manner as described above.
A gas recovery hole 14 is formed therein, and a recovery pipe 15 is connected to the gas recovery hole 14.

The machining gap between the machining electrode 2 and the machining surface of the workpiece S can be rigidly adjusted by moving the Z-axis stage, but as shown in FIGS. 12 to 14, atmospheric gas is If the structure is such that the gas is supplied to the machining surface, the machining electrode 2 can be floated by the dynamic pressure of the ejected atmospheric gas. That is, by adjusting the gas pressure supplied by the supply pipe 12, the machining gap can be adjusted in a gas-bearing manner using the pressure of the atmospheric gas ejected from the ejection port 10.

Furthermore, FIGS. 15 and 16 mainly show the workpiece S.
Flat blade-shaped processing electrode 2 used for cutting
An example of this is shown. This is because the machining groove becomes deeper as the cutting progresses, and ordinary gas supply means cannot sufficiently supply the atmospheric gas containing the reaction gas. It has been established.

More specifically, the processing electrode 2 shown in FIG.
, ... are interposed to fix the flat surface plates 21, 21, and the gap between the electrode 6 and one surface plate 21 is connected to the gas supply path 18.
This structure has a structure in which the gap between the surface plate 21 and the other surface plate 21 is used as a gas recovery path 19. In this case, the tips of the electrodes 6 are made to protrude from both surface plates 21, 21.

The processing electrode 2 shown in FIG. 16 has a large number of grooves 2 on both sides of a flat intermediate plate 22 extending from the base end toward the distal end.
3,... are formed, and the surface plates 21, 21 are joined from both sides thereof, and the gas supply path 18 is partitioned by the groove 23 and the surface plate 21.
A rod-shaped electrode 6 coated with a material having corrosion resistance against reaction gases and neutral radicals is fixed along the tip of the intermediate plate 22, and a gas recovery path 19 is formed on both sides of the electrode. This is a structure in which the gas supply path 18 and the gas recovery path 19 are open. Here, the intermediate plate 22 and the surface plate 21 are made of ceramics.

The structure of the processing electrode shown above is one in which a reactive gas and an inert gas are supplied simultaneously, and plasma from the inert gas and neutral radicals based on the reactive gas are generated in the same area. As shown, first a plasma is generated using an inert gas, then it is transferred toward the processing surface of the workpiece S, and collides with a reactive gas in an area different from the plasma generation area to generate neutral radicals. It is. More specifically, in addition to having a structure substantially similar to that of the processing electrode 2 shown in FIG. The plasma is generated between the tip of the electrode 6 and the tip of the electrode 6, and the plasma is ionized and excited, and the plasma is transferred to the jet nozzle 10 by the gas pressure, and a flexible reaction gas supply pipe 25 and Gas introduction pipe 26
This structure is such that neutral radicals are generated and supplied to the processing surface of the workpiece S by colliding with the reaction gas supplied through the reactor gas. In this way, there is no fear that the generated plasma will come into contact with the processing surface, and the temperature of the processing surface will hardly rise, so processing can be performed at lower temperatures. It is also effective when using a reactive gas that captures electrons in the plasma and has a negative effect on the plasma state, such as when using a halogen gas.

[0043]

[Effects of the Invention] According to the strain-free precision numerical control processing method and its apparatus by radical reaction of the present invention, as described above,
Between the machining time with a machining electrode at a certain point on the machining surface of the workpiece and the amount of machining that progresses by removing volatile substances through radical reactions between neutral radicals and atoms or molecules that make up the machining surface. Utilizing the fact that there is a correlation between

In addition, since the scanning speed, which can be controlled accurately and with high repeatability, or the stopping time in the case of stepwise scanning is used as a control variable, the optimum machining time at a certain point on the machining surface can be determined. It is possible to set accurately and easily, and numerical control becomes easy.

Furthermore, when measuring the shape of the pre-processed surface before starting processing and inputting the coordinate data to the control circuit,
Since the relative scanning speed or stop time of the machining electrode and the workpiece is calculated in advance, the number of coordinate calculations during machining can be reduced, making high-speed machining possible.

When the shape of the pre-processed surface is measured during processing and the coordinate data is input to the control circuit, the optimum scanning speed or stop time is calculated as the processing progresses, so that the processing Since it is possible to proceed while correcting machining errors inside, accuracy can be further improved.

[Brief explanation of the drawing]

[Fig. 1] Conceptual diagram of the device of the present invention

[Figure 2] Control block diagram of drive servo motor

[Figure 3]
Conceptual diagram of wide area processing using spot scanning

[Figure 4] Conceptual diagram showing the relationship between the pre-processed surface and the target processed surface

[Figure 5] Block diagram showing the procedure of numerical control machining

[Figure 6] Flowchart of numerical control software

[Figure 7] Flowchart showing the first half of the subroutine of numerical control software

[Figure 8] Flowchart showing the second half of the subroutine of numerical control software

[Figure 9] Conceptual diagram of acceleration/deceleration control in scanning

[Fig. 10] A simplified perspective view showing an example of an electric field dispersion type machining electrode

[Fig. 11] A simplified perspective view showing another example of an electric field concentration type processing electrode.

[Figure 12] A simplified cross-sectional view showing an example of an internally generated processing electrode

[Fig. 13] A simplified cross-sectional view showing another example of an internally generated processing electrode

[Fig. 14] A simplified cross-sectional view showing another example of an externally generated processing electrode.

[Fig. 15] Partially simplified perspective view showing an example of a blade-type processing electrode

[Fig. 16] Partially simplified perspective view showing another example of a blade-type processing electrode

[Fig. 17] A simplified cross-sectional view showing an example of an internally generated processing electrode in which the plasma generation region and the neutral radical generation region are different.

[Explanation of symbols]

Claims (6)

[Claims] Claim 1: Neutral radicals based on a reaction gas generated by a machining electrode to which a high voltage is applied are supplied to the machining surface, and volatile substances are generated by a radical reaction between the neutral radicals and atoms or molecules on the machining surface. Distortion-free precision numerically controlled machining that involves vaporizing and removing substances, and numerically controlling the machining time according to the coordinate difference based on the coordinate data of the pre-machined surface and the target machining surface. Method. [Claim 2] Before starting machining, measure the shape of the pre-machined surface, input the coordinate data of the pre-machined surface and the target machining surface to a control circuit, and perform numerical control by the control circuit according to the coordinate difference between the two machining surfaces. 2. The strain-free precision numerical control machining method using radical reaction according to claim 1, wherein the relative scanning speed of the machining electrode and the workpiece is controlled by a drive mechanism that is controlled by a drive mechanism. 3. Before starting machining, the shape of the pre-machined surface is measured, the coordinate data of the pre-machined surface and the target machining surface are input to a control circuit, and a drive mechanism numerically controlled by the control circuit drives the machining electrode. 2. The strain-free precision numerical control machining method using radical reaction according to claim 1, wherein the workpiece is scanned relatively stepwise and the stopping time thereof is controlled according to the coordinate difference between the two machining surfaces. 4. Measure the shape of the pre-machined surface while machining is in progress, input the coordinate data of the pre-machined surface and the target machining surface to a control circuit, and perform numerical control by the control circuit according to the coordinate difference between the two machining surfaces. 2. The strain-free precision numerical control machining method using radical reaction according to claim 1, wherein the relative scanning speed of the machining electrode and the workpiece is controlled by a drive mechanism that is controlled by a drive mechanism. 5. While machining is in progress, the shape of the pre-machined surface is measured, the coordinate data of the pre-machined surface and the target machining surface are input to a control circuit, and a drive mechanism numerically controlled by the control circuit drives the machining electrode. 2. The strain-free precision numerical control machining method using radical reaction according to claim 1, wherein the workpiece is scanned relatively stepwise and the stopping time thereof is controlled according to the coordinate difference between the two machining surfaces. 6. A reaction vessel in which an atmospheric gas containing a reaction gas can be sealed or flowed under high pressure, a processing electrode arranged in the reaction vessel, and a DC or AC high voltage applied to the processing electrode to process the reaction gas. a drive mechanism having a servo motor capable of displacing one of the processing electrode or the workpiece relative to the other; A measuring means for measuring the shape of the pre-processed surface, the processing time using the processing electrode, and the amount of processing that can be removed by vaporizing volatile substances generated by the radical reaction between neutral radicals and atoms or molecules on the processing surface. It is possible to input the coordinate data of the pre-machined surface and the target machining surface of the workpiece, and drive the control signal related to the relative scanning of the workpiece and the machining electrode according to the coordinate difference between them. Distortion-free precision numerical control processing equipment using radical reaction, characterized by a control circuit that outputs to the mechanism, and the following.