TW201900305A - Back-drilling processing method for multilayer printed wiring board and substrate processing apparatus in which the processing depth of the back-drilling process can be controlled accurately and precisely - Google Patents

Abstract

In the back-drilling processing, it is possible to prevent elongating the reserved error margin caused by errors such as inclination or deflection respectively existing in the processing table, the lower plate and the substrate, thereby providing an accurate and precise back-drilling processing, and the reserved error margin can be designed to be set shorter. The descending distance information is detected by the drill bit itself which performs the back-drilling processing, and the actual distance to the desired conductor layer is calculated via a certain calculation formula based on the acquired descending distance information. By further modifying the distance, the processing depth of the back-drilling process can be controlled accurately and precisely.

Description

 Back-drilling processing method of multilayer printed wiring board and substrate processing apparatus  

The present invention relates to a back-drilling processing method for a multilayer printed wiring board, and a substrate processing apparatus suitable for implementing the processing method.

In the past, with the demand for ultra-high-speed control of electronic equipment, multilayer printed wiring and high density have been pursued for printed wiring boards. In such a multilayer printed wiring board, a through hole (through hole) is provided in order to be mounted between, for example, an electronic component or a multilayer printed wiring, and a conductive plating process of a predetermined thickness is applied thereto. For example, as shown in FIG. 2, the surface conductor layer 107 composed of a copper foil portion and the back surface conductor layer 108 are provided on the upper and lower sides thereof, and the substrate 101 to which the wiring pattern is finally applied to the surface conductor layer 107 and the back surface conductor layer 108 is finally provided. The first inner conductive layer 102 is disposed between the first insulating layer 103 and the second insulating layer 104, or the second inner conductive layer 106 is disposed between the second insulating layer 104 and the third insulating layer 105. When the first built-in conductor layer 102 is connected to the conductor layer to be formed to connect the back surface conductor layer 108, a through hole penetrating the substrate 101 itself is provided, and plating is applied thereto to form a hole portion 109 penetrating the substrate 101 in the vertical direction. A plating portion 110 of a predetermined thickness. The plated portion 110 is connected to the first inner conductor layer 102 to which the back conductor layer 108 is to be connected. However, in this state, the excess length perforated portion (hereinafter referred to as "excess portion") remains and extends to the surface conductor layer 107.

When the remaining length portion remains, for example, when the control frequency reaches several GHz or more at the time of high-speed transmission or the like, reflection or attenuation occurs in the excess length portion, which may cause noise such as noise in the electronic device used for the substrate 101. The reason for the condition is that the substrate 101 itself is rated as a defective product. Therefore, when the processing for removing the excess length portion is performed, it is necessary to perform a back drilling process to remove the excess plating portion 110 and to minimize the excess length portion.

In the back-drilling process as described above, since the remaining excess length portion causes a problem such as noise, it is desirable to remove the plating portion 110 to the maximum extent, that is, the remaining length portion is zero. On the other hand, since the thickness of the first inner conductor layer 102 sandwiched between the insulating layers is 12 to 25 μm, in order to maintain the back conductor layer 108 and the first inner conductor layer 102, it is necessary to reach the first The backdrilling process is stopped before the built-in conductor layer 102. Therefore, it is necessary to correctly control the depth of the back-drilling process, in reality, due to the inclination or bending of the processing table itself of the processing apparatus, the individual thickness of the lower plate used for processing, the individual substrate itself, or before cutting out the plurality of substrates. The depth of the substrate mother board, the error caused by the measuring device, and the like, make it difficult to accurately control the depth of the back drilling process. Therefore, when the substrate manufacturer employs the substrate processing industry to perform the processing of the substrate, it is necessary to consider the error that may occur during the back-drilling process, and deliberately does not reduce the length of the remaining excess length portion to zero, and designates to retain a certain number of Length, as a residual amount on the design.

Thus, even if there is a certain length of the allowable range as the length of the excess length portion during the processing of the substrate, it is necessary to process as close as possible to the numerical value within the allowable range of the plurality of holes, so that in the correct control of the depth of the back drilling process , using the method of using the probe. In other words, the tip end of the probe is used as a reference position (a point of 0 in the Z-axis coordinate position), and the position of the tip end of the drill provided at the tip end of the rotor of the rotating shaft is set in the substrate processing apparatus in which the rotating shaft is mounted. At the same height as the tip end position of the probe, the distance (M) from the reference position of the probe to the substrate is calculated by measuring the height position of the substrate placed on the processing table using a probe. The length of the plating portion from the conductor layer to the surface conductor layer 107, which is not only the thickness of the substrate itself, is the reference length (Lnd), and the length of the design tolerance range of the plating portion. (td) is a design value determined by the substrate manufacturer beforehand. Therefore, the value after subtracting the length (td) of the reserved error range from the reference residual length (Lnd) becomes the reference backdrill depth (L2d), and from the foregoing The distance (M) between the probe reference position measured by the probe to the substrate and the reference backdrill depth (L2d) is the moving distance of the drill. Therefore, the back drilling process is performed by lowering the drill bit to the calculated moving distance.

However, when the depth of the back-drilling process is controlled by this method, it is difficult to control correctly for the following reasons. That is, first, the tip end position of the probe is displaced from the position of the drill tip position provided on the rotating shaft. The probe is also an individual different from the drill bit, so it is very difficult to completely match the position of the tip. Generally, it is inevitable that there is an error of about ±20 μm. Second, in the processing table of the substrate processing apparatus used in the back-drilling process, the height of the processing table varies with each machining position. In the case of a plurality of substrate processing apparatuses, the height of the processing table at each of the processing stages is measured. It has been found that a large number of processing stages themselves have a height difference of about ±50 μm with each processing position. Third, there is a difference in the thickness of the lower plate used in processing relative to its preset thickness. For the measurement of the thickness of most of the lower plates, it has been found that there is probably a difference of about ± 20 μm. Fourth, regarding the multilayer printed wiring board itself, there is a difference with respect to its preset thickness. In general, a multilayer printed wiring board is formed by alternately heating and compressing a resin layer and a conductor wiring layer. Therefore, even if the thickness of each layer of the substrate or the entire thickness of the substrate is designed to have a design size, it is actually used as a product. Of course, in addition to the thickness of each layer, the thickness of the substrate itself may vary. Actually, the error of the substrate and the design value was measured for many substrates, and it was found that the thickness of the substrate was approximately different by about ± 30 μm. In particular, in the multilayer printed wiring board, the conductor layer as the wiring is not uniformly distributed among all the resin layers, and for example, a conductor layer of twenty layers is provided in a certain portion of a certain substrate, but it is possible to provide only eight layers in other portions. The conductor layer is such that even in a single-piece substrate, the arrangement of the conductor layers is not uniform, and in the same substrate, a portion in which twenty conductor layers are provided and a portion in which only eight conductor layers are provided are provided. Than, the tendency of own thicker plate thickness.

As described above, during back-drilling, errors of up to ±120 μm are caused by these deviations. Therefore, in order to reduce this deviation, even if it is desired to eliminate the deviation of the processing table height which accounts for a large proportion of the above-mentioned deviations, the maintenance and repair required for it requires a highly sophisticated technique, which requires not only excessive time and cost but also topping. It can only be reduced by about ±20μm. As a result, even if such a large amount of time and cost is spent, there is still an error of about ±90 μm, and it is difficult to satisfy the customer's required back drilling with an error of about ±50 μm with respect to the reference error range of the design value. The standard for depth control of machining.

Therefore, in order to more accurately control the depth of the back-drilling process, as shown in the patent JP-A-2014-33006, it is provided that a coupon to be tested is provided outside the wiring area of the substrate, according to the back there. The depth information obtained by the drilling process to control the machining depth of the back drilling process at an appropriate position.

However, since other samples are additionally provided in addition to the perforation of the back-drilling process, it is still difficult to accurately and precisely control the processing depth of the back-drilling process, and there is a disadvantage that the manufacturing cost of the substrate of the product is increased.

On the other hand, as described above, if a probe is provided in addition to the drill itself to measure the height of the substrate or the like, the position of the tip end of the probe and the position of the tip end of the drill provided on the rotating shaft may be displaced, so that the shaft is rotated. In fact, the back-drilling process of the substrate causes an error of about ±20 μm when the light is displaced. Therefore, in order to eliminate this error, as shown in the patent JP-A-2014-187153, there has been provided a method of directly detecting the depth position in the substrate by the drill bit and controlling the machining depth of the back-drilling processing based on the position.

However, in this method, it is still necessary to provide a voltage detecting layer in addition to an appropriate internal wiring layer, so that the processing depth of the back-drilling processing cannot be accurately and precisely controlled, and there is a disadvantage that the manufacturing cost of the substrate is increased.

Patent Document 1: JP 2014-33006

Patent Document 2: JP 2014-187153

The problem to be solved by the present invention is that in the back-drilling processing of the multilayer printed wiring board, the processing depth must be accurately and precisely controlled. However, if the individual probes are different from the drill shaft in the substrate processing apparatus, the processing is performed. The position of the height of the substrate in the position, and the depth of the back drilling process is determined according to the thickness of the substrate itself, the reference residual length (Lnd), and the reference remaining error range (td) determined as the design value, The position of the position itself is deviated from the position of the probe position, and the difference between the design value of the substrate and the actual thickness makes it difficult to accurately and precisely control the machining depth, and methods other than this method are difficult to accurately and precisely control the machining depth, and The problem of the manufacturing cost of the substrate as a product is increased.

In the invention of the present application, first, the measurement error caused by the inclination or deflection of the processing table itself of the substrate processing apparatus and the inclination or deflection of the lower plate itself used in the processing is suppressed. At the same time, at the same time, in the case of individual substrates in a multilayer printed wiring board, and in a single substrate, there are also slight differences in thickness between the respective portions, and differences in the height positions of the conductor layers are found. In the inner conductor layer to be processed by the machining depth during back drilling, the actual height position deviation from the reference length of the design value, and the thickness of the substrate itself including the conductor layer, relative to the actual value of the design value The deviation of the thickness is related to the two kinds of deviations, and the correlation information is used to accumulate and calculate the detected falling distance information together with the falling distance information detecting mechanism of the drill bit to achieve the back drilling process. Correct and precise machining depth control. Secondly, it is a processing apparatus that provides a control mechanism that achieves accurate and precise machining depth control in back-drilling processing, and further provides a control method of back-drilling processing using the processing apparatus.

The invention of the present application is a processing depth control mechanism which is a substrate processing apparatus capable of back-drilling a multilayer printed wiring board using a computer, and controls a falling distance of a drill of a rotating shaft during back drilling.

The machining depth control means includes a falling distance information detecting means for detecting a falling distance information by contacting a detecting object with a rotating shaft, and having a recording medium, an extracting means, and a calculating means.

In the recording medium, position information and the like described in the following 1 to 5 are recorded: 1. The length of the substrate thickness, the reference residual length, and the design reserved error range (residual amount), and the perforation. Numerical information of the predetermined thickness of the layer of the plating layer of the hole portion and the angle of the tip angle of the drill bit; 2. placed on the processing table of the substrate processing apparatus, and at least the upper surface is formed as a lower layer of the conductor layer, as follows Setting the determined measurement point and the coordinate position information of each area on the plane, and the measurement point is: a measurement point in which a plurality of areas are separated by a grid-like area, and each area is determined by the same reference. Or, in each of the regions, a sub-region that is further divided into a lattice shape on the same basis for each region, and a measurement point determined by the same reference unit in each sub-region; The measurement point is obtained by lowering the rotation axis provided by the drill bit for back-drilling, and the height position information of each measurement point measured by the falling distance information detecting means; 4. being present on the loading base The back-drilled layer on the multilayer printed wiring board on the lower plate on the processing table of the plate processing apparatus or the mother board (hereinafter simply referred to as "mother board") present in front of the plurality of multilayer printed wiring boards Coordinate position information of the processing position on the plane; 5. By lowering the rotation axis to the back drilling processing position of the substrate or the mother board, each of the respective back drilling processing positions measured by the falling distance information detecting mechanism is individual Height location information.

The extraction mechanism extracts the multilayer printed wiring substrate on the lower plate during back-drilling processing from the individual coordinate position information of each of the regions and the coordinate position information of the back-drilling processing position existing on the multilayer printed wiring board or the mother board thereof. In the state of its mother board or the mother board, there is a back-drilling processing position in each coordinate range of each region of the lower plate.

The calculation means calculates the individual back-drilling depth L2c based on the following formula, and automatically controls the machining depth of the back-drilling in the substrate processing apparatus.

L2c=Lnd×(L2m-αave)/L2d-td+corner tan1

Lnd=Design base length

L2m=Extracting the measured height of each of the back-drilling processing positions in the individual coordinate value ranges of the respective regions existing in the respective regions of the lower plate in the multilayer printed wiring board or the mother board placed on the lower plate on the processing table

Aveave = average of the measured heights of the measured points of individual areas in the lower plate on the processing table

L2d=Design multilayer printed wiring substrate thickness

Td=the length of the design's reserved error range

Angle tan1 = predetermined thickness of the layer of the perforated plated portion × tan {(180 degrees - angle of the tip angle of the drill bit) ÷ 2}

By processing the depth control mechanism, the following advantages can be achieved.

First, the lower plate is divided into individual regions, the measurement points are extracted for the individual regions, the average value of the height of the region is calculated from the height position information of the measurement points, and the position existing in the corresponding region is simultaneously extracted. The back drilling processing position of the substrate can accurately detect the substrate itself in the back drilling processing by subtracting the average value of the height of the lower plate in the region from the height of the measurement (that is, L2m-αave in the calculation formula) The thickness of the location. And because of the difference between the thickness of the substrate itself in the back-drilling processing position and the thickness of the substrate itself, the actual thickness position of the substrate of the ideal conductor layer and the thickness position of the design. Since the difference relationship has a correlation relationship, it is possible to recognize the actual thickness position of the substrate of the ideal conductor layer which cannot be measured without destroying the substrate itself by performing correction according to the correlation relationship, and perform more precise back drilling processing. . Further, the height information of the back-drilling processing position of the substrate can be determined by the front end angle of the drill bit for performing the back-drilling process, and the inclined portion of the drill bit contacts the plating portion provided in the hole portion of the through hole with respect to the inner side of the hole portion. Detected. At the same time, the upper end portion of the reserved error range is such that the oblique cutting is longer with respect to the outer side of the hole portion and the inner side is shorter, and the length of the design reference error tolerance range is determined to be the longer portion on the outer side. Therefore, it is possible to calculate the length of the plating portion, that is, the length of the excess length portion before reaching the desired conductor layer, and the position after deducting the length of the design reference error range from the length is determined outside the plating portion. However, since the tip end of the drill bit has an inclined portion, and as described above, the measurement of the height position of the substrate requires that the inclined portion of the drill bit contacts the plating portion of the hole portion provided in the through hole with respect to the inner side of the hole portion, so that the back is to be performed. The drill is machined to that position and must be machined to a position deeper inside the plated portion than on the outside. That is, a deviation of the height position occurs between the inner side and the outer side with respect to the thickness of the plated portion, and the deviation of the height can be corrected by calculating the angle tan1. As a result of this, even if the predetermined error range of the design value remaining in the perforation after the back-drilling processing is set to be short, the length of the reserved error range can be correctly realized. Therefore, it is not necessary to set the reserved error range on the premise of a large error, and the reserved error range itself is set to be short so as to correctly realize the size thereof, and it is possible to suppress a problem such as noise caused by the remaining excess length portion. occur. Further, the machining depth control means can be configured by adding a recording medium, an extracting means, and a calculating means to the falling distance information detecting means of the drill which uses the rotating shaft, so that the substrate processing apparatus having the falling distance information detecting means can be modified at low cost.

Secondly, since the descending distance information is not detected by an individual different from the drill such as a probe, the falling distance information is detected by the drill itself used in the back drilling process, thereby preventing the origin of the height direction at the time of detection. The error caused by the deviation of the zero position occurs.

Third, since the processing apparatus is controlled by a computer, it is not necessary to perform special samples or wiring on the multilayer printed wiring board, and the manufacturing cost of the substrate itself can be reduced.

In addition, the falling distance information detecting mechanism is more specifically a high-frequency AC power source, a bypass circuit with a reactor, and a high-frequency converter, and one side of the output of the high-frequency AC power source is connected to the connection housing. The other side is connected to the rotating shaft insulated from the casing via the aforementioned converter, and between the connection with the rotating shaft, a bypass circuit connecting casing with a reactor is provided, and the drill bit contact of the rotor of the rotating shaft belongs to The object to be detected by the conductor causes a high-frequency current from the high-frequency AC power source to flow into the rotating shaft via the current transformer, and flows into the high-frequency AC power source via the capacitance between the conductor and the conductor layer to generate a current on the output side of the converter. And by detecting the change of the current by the detector, the falling distance information of the drill bit can be recognized.

Therefore, when it is determined whether or not there is a contact object to be detected at the tip end of the rotating shaft, the external defect is unlikely to occur, or even if it occurs, the external defect has little influence on the determination accuracy, or In the case where a filter or the like is excluded from the configuration of the external defect factor, a falling distance information detecting means having sufficient determination accuracy can be constructed, and a connection is provided between the input winding of the connected converter and the connecting line of the rotating shaft. The bypass circuit between the housings makes the shaft no longer a so-called floating metal, and it is not necessary to provide a protection function against electric shock. Further, it is possible to further cause a current such as a harmonic current to flow through the drill to the casing, thereby preventing damage to the metal surface of the drill or the surface of the drill due to the current, and the drill can be used for a long period of time.

In addition, another configuration of the falling distance information detecting mechanism may be a high-frequency AC power supply, a bypass circuit with a reactor, a cancel circuit, and an input winding, a winding elimination, and one or more output windings. In the high-frequency current transformer, the input winding wire and the eliminating winding wire are the same number of coils but the winding direction is opposite, and the eliminating circuit has an inverse bypass circuit and a plurality of sets of analog circuits, and the reverse bypass circuit has The bypass circuit has the same electrostatic capacity reactor, and each set of analog circuits is formed by a capacitor and a switch arranged in series, and the capacitor of the complex array is arranged in parallel with the switch as an analog circuit, and when the housing is When the insulated rotating shaft is energized, the analog circuits of the sets respectively correspond to the respective electrostatic capacitances between the winding line and the rotating shaft body of each phase of the motor that generates the rotating shaft, and between the rotating shaft body and the housing, and the reverse bypass circuit and the plurality of sets The analog circuit is arranged in parallel, by fixing the object to be detected on a processing table in the casing of the substrate processing apparatus, and the aforementioned high-frequency alternating current One side of the output is connected to the housing, and the other side is connected to the middle of the input winding and the unwinding line of the current converter, so that the other end of the input winding is connected to the rotating shaft body, and the housing is connected via the bypass circuit to eliminate the winding. The other end is connected in parallel with one end of the reverse bypass circuit and one end of each analog circuit, and the other end of the reverse bypass circuit is connected to the housing, and the analog circuit corresponding to the electrostatic capacitance generated between the housing and the rotating shaft insulated from the rotating shaft body is another The other end of the analog circuit corresponding to the electrostatic capacitance generated between the one end of the housing and the motor shaft winding is connected to the winding of each phase of the motor of the rotating shaft, and the switch of the analog circuit is adjusted so that the corresponding electrostatic capacitances are substantially equal. The direction of the magnetic flux generated in the current transformer due to the current flowing through the input winding and the eliminating winding is canceled, and the change in the current generated by the contact between the tip of the rotating shaft and the object to be detected can be detected from the detector. The change of the current output from the converter is configured to recognize the falling distance information of the drill bit.

In addition, the falling distance information detecting mechanism has another configuration, and may be a high-frequency inverter having a high-frequency AC power supply, two input windings having the same number of coils, and one or more output windings, and an analog substrate circuit. The substrate circuit is a capacitor and a switch arranged in series, and the capacitor of the multiple array is arranged in parallel with the switch, and one side of the output of the high-frequency AC power source is connected to the housing and connected to one side terminal of the analog substrate circuit. The other side is connected to the other end of the analog substrate circuit via the two input winding wires of the current transformer, and is fixed to the housing of the substrate processing apparatus by adjusting the switch of the analog substrate circuit. The electrostatic capacitance generated between the object to be detected on the processing table in the casing and the casing is slightly equal, so that the input winding current causes the magnetic fluxes generated by the current transformer to cancel each other, and the front end of the drill shaft of the rotating shaft can be detected from the detector. A change in current generated by contact with the object to be detected is formed as a discernible drill as a change in current output from the converter Head drop distance information.

By using the falling distance information detecting mechanism having these configurations, it is possible to more accurately and accurately measure the height position of the drill bit itself, and thus the machining depth control of the back drilling process can be performed more precisely. It is also possible to limit the length of the margin of error remaining in the perforations after back-drilling to a minimum.

Moreover, the present invention also provides a substrate processing apparatus including any of the above-described processing depth control mechanisms.

In another aspect, the present invention also provides a back-drilling processing method using any of the foregoing substrate processing apparatuses, wherein: 1. regarding a substrate thickness, a reference margin, and a design margin (residual amount) in design The length, and the numerical information of the predetermined thickness of the layer of the plating layer provided on the hole portion of the perforation and the angle of the tip angle of the drill bit; 2. Loading on the processing table of the substrate processing apparatus, and at least the upper surface is configured as a conductor layer In the lower plate, the measurement point determined by the following setting and the coordinate position information of each area on the plane, and the measurement point is: the area in which the grid area is separated by a plurality of areas, in units of each area, and the same One measurement point determined by the reference, or a sub-region in which each region is further divided into a lattice-like sub-region on the same basis, and each sub-region is determined by the same reference. 3. For each of the above-mentioned measurement points, the height of each measurement point measured by the falling distance information detecting means is lowered by the rotation axis provided by the drill bit for performing the back drilling process. 4. The information is present on the multilayer printed wiring board on the lower plate placed on the processing table of the substrate processing apparatus, or on the mother board in front of the plurality of printed wiring boards (hereinafter referred to as Information on the coordinate position of each back-drilling processing position on the plane on the "mother board"; 5. By measuring the rotating shaft to the back-drilling processing position of the substrate or the mother board, the falling distance information detecting mechanism determines The individual height position information of each of the back drilling processing positions.

The position information and the like described in each of the above 1 to 5 are recorded on the recording medium, and the coordinate position information of each of the respective regions and the coordinate position of the back drilling processing position existing on the multilayer printed wiring board or the mother board thereof are recorded. In the state in which the multilayer printed wiring board or its mother board is placed on the lower board during the back-drilling process, the back-drilling processing position exists in each coordinate range of each area of the lower board.

Further, the machining depth of the back drilling processing in the substrate processing apparatus is automatically controlled based on the individual back drilling processing depth L2c which is automatically calculated by the following formula.

L2c=Lnd×(L2m-αave)/L2d-td+corner tan1

Lnd=Design base length

L2m=Extracting the measured height of each of the back-drilling processing positions in the individual coordinate value ranges of the respective regions existing in the respective regions of the lower plate in the multilayer printed wiring board or the mother board placed on the lower plate on the processing table

Aveave = average of the measured heights of the measured points of individual areas in the lower plate on the processing table

L2d=Design multilayer printed wiring substrate thickness

Td=the length of the design's reserved error range

Angle tan1 = predetermined thickness of the layer of the perforated plated portion × tan {(180 degrees - angle of the tip angle of the drill bit) ÷ 2}

By using the substrate processing apparatus as described above, it is possible to perform more accurate and precise processing in accordance with the back-drilling processing position of each substrate without increasing the unnecessary manufacturing cost, even if it is a design value remaining in the perforation after the back-drilling process. The error margin is set to be shorter, and the reserved error range can also be correctly implemented. Therefore, it is not necessary to determine the reserved error range on the premise of a large error, and the size of the reserved error range itself is set to be short to correctly realize the size, and the noise caused by the residual portion can be suppressed. occur.

Further, although the plating portion is cut by the end portion of the drill to the perforated hole portion, the cutting portion of the drill is the inclined portion instead of the tip end corner portion. Therefore, not only the position of the top end of the front end corner of the drill bit but also the position of the inclined portion of the drill bit in which the margin of error is drawn, the upper end portion of the reserved error range is obliquely cut to be relative to the hole portion. The outer side is longer and the inner side is shorter. Therefore, although the length of the reference reservation error range is determined at the front end position on the outer side with respect to the hole portion, the deviation between the inner side and the outer side of the plating portion which is the predetermined error range is calculated by referring to the plating portion. The angle tan1 of the predetermined thickness is calculated and corrected. That is, the back-drilling can be performed more precisely by calculating the value calculated by the predetermined thickness of the layer of the perforated plated portion × tan {(180 degrees - the angle of the tip angle of the drill bit) ÷ 2} Machining depth control.

In addition, the back-drilling processing method using any of the above-described substrate processing apparatuses may be: 1. the length of the substrate thickness, the reference residual length, and the design reserved error range (residual amount) of the design, and not set. Numerical information of the radius of the perforated hole portion of the plating portion to be back-drilled and the angle of the tip angle of the drill bit; 2. placed on the processing table of the substrate processing apparatus, and at least the upper surface is configured as a lower layer of the conductor layer The measurement point determined by the following setting and the coordinate position information of each area on the plane, and the measurement point is: a region in which a plurality of grid-shaped regions are separated, determined by each region, and determined on the same basis One measurement point or one measurement point determined by dividing the sub-region into a grid on the same basis for each region in the respective regions and determining the same sub-region 3. For each of the above-mentioned measurement points, the height of each measurement point measured by the lowering distance information detecting means is lowered by lowering the rotating shaft provided by the drill bit for back drilling processing. 4. The motherboard is placed on the multilayer printed wiring board on the lower board placed on the processing table of the substrate processing apparatus, or is present on the mother board in front of the plurality of multilayer printed wiring boards (hereinafter referred to as " Information on the coordinate position of each back-drilling processing position on the mother board"; 5. In the state where the substrate or the mother board is placed with the aluminum upper plate of a known thickness, the rotating shaft is lowered to Each of the back-drilling processing positions is an individual height position information of each of the back-drilling processing positions measured by the falling distance information detecting means.

The position information and the like described in each of the above 1 to 5 are recorded on the recording medium, and the coordinate position information of each of the respective regions and the coordinate position of the back drilling processing position existing on the multilayer printed wiring board or the mother board thereof are recorded. In the state in which the multilayer printed wiring board or its mother board is placed on the lower board during the back-drilling process, the back-drilling processing position exists in each coordinate range of each area of the lower board.

Further, the machining depth of the back drilling process in the substrate processing apparatus is automatically controlled based on the individual back drilling depth L2c automatically calculated by the following formula.

L2c=Lnd×(L2m1-αave-tAL)/L2d-td+tAL+corner tan2

Lnd=Design base length

L2m1=Multilayer printed wiring board or its mother board placed on the lower plate on the processing table, and further mounted on the upper surface of the aluminum plate with a known thickness, and extracted as each region existing in the lower plate Measured height of each back-drilling machining position in an individual coordinate range

Aveave = average of the measured heights of the measured points of individual areas in the lower plate on the processing table

L2d=Design multilayer printed wiring substrate thickness

Td=the length of the design's reserved error range

tAL=Specified thickness of the upper plate of aluminum

Angle tan2=predetermined thickness of perforation without plating portion × tan{(180 degrees - angle of front end angle of drill bit) ÷ 2}

Thereby, the following error can be prevented, and precise back drilling processing can be performed. That is, first, there is an opening due to the presence of the perforated hole portion in the back drilling processing position, that is, the hole portion of the substrate surface has no conductor layer, and the front end of the drill bit is the front end corner top having the front end angle, At the start of the back-drilling process, the center of the hole portion where the perforation may occur is deviated from the center of the center of the drill bit subjected to the back-drilling process. When this core deviation occurs, the value of the substrate itself and the actual height position may be incorrectly determined due to the inability to correctly measure the height of the substrate in the back-drilling processing position, and the processing depth of the individual back bit calculated on the premise of the value is also An error has occurred. Therefore, in order to cause the core deviation to occur, these errors do not occur, and the height position of the upper plate of the aluminum material placed on the substrate is measured, and finally the thickness of the upper plate of the aluminum material is calculated. Corrected. Secondly, as described above, there is an opening in which the perforated hole portion exists in the back drilling processing position, so that the core deviation caused by the skew of the drill bit may occur in the back drilling process. In the case where the core deviation occurs, when the machining depth control of the back drilling process is performed, the length of the reserved error range of the plating portion fails to be a result of the control, and an error occurs. Therefore, the back drilling process is performed in a state in which the aluminum upper plate is placed on the substrate, in order to prevent the drill from being skewed during the back drilling process. Thirdly, the height position of the upper plate of the aluminum material loaded on the substrate is measured by contacting the top plate of the aluminum material with the top end of the drill bit, and the tip end of the drill bit is moved in the hole of the perforation. In the plating section, the drill portion is an inclined portion cutting plating portion instead of the front end corner portion. Therefore, the position of the top end of the drill bit and the reserved error range defining the remaining length portion (the upper end portion of the reserved error range is inclined to be longer than the outer side of the hole portion and the inner side is shorter, and the margin of error is reserved) The length is determined to vary between the positions of the inclined portions at the front end position with respect to the hole portion. This deviation is the angle tan2, which is equivalent to the radius to be perforated without the plating portion × tan {(180 degrees - the angle of the front end angle of the drill bit) ÷ 2}, in the foregoing method, the deviation is calculated from the calculation, The machining depth of the back drilling process can be controlled accurately and precisely.

In addition, the foregoing back-drilling processing method can further mount an aluminum-on-board having a known thickness on a multilayer printed wiring board or a mother board on a lower plate placed on a processing table during back-drilling processing, and further An insulating upper plate that can be cut by a rotating shaft is placed thereon.

Thereby, the following error can be prevented, and more accurate and precise back-drilling processing can be continuously performed. That is, since the inner surface of the hole through which the back drilling is performed is subjected to plating processing to form the plating portion, if the back drilling process is performed, linear chips are generated from the conductive plating portion and adhere to the drill. Therefore, when the drill to which the chip is attached is used, the height of the lower plate or the substrate is measured during the preparation of the back-drilling process, and the measurement error caused by the conductive chips adhering thereto is caused. By placing the aluminum upper plate on the insulating upper plate, it is possible to generate chips from the insulating upper plate in the subsequent back-drilling process, and the chips attached to the drill can be pushed away to automatically It leaves the drill bit. Thereby, even if the height of the lower plate or the substrate is measured using the drill, it is possible to prevent an error caused by the chips of the plating portion.

According to the processing depth control mechanism of the back-drilling process of the invention of claim 1, since the depth of the back-drilling process for the substrate can be controlled at a low cost, accurately and precisely, the noise caused by the processed substrate can be eliminated. Such an unfavorable situation has an excellent effect of being able to manufacture the substrate itself at low cost. Further, since the machining depth control mechanism can be manufactured by adding a substrate processing apparatus having a falling distance information detecting mechanism, it is possible to provide a substrate processing apparatus which can provide a low-cost and accurate and precise back drilling process. effect.

The machining depth control mechanism of the back-drilling process of the invention described in claim 2 can achieve more precise machining depth control by the simple falling distance information detecting mechanism, and can ensure the safety against electric shock without damaging the drill bit. Life expectancy.

The processing depth control mechanism for the back-drilling processing of the invention described in claims 3 to 4 can eliminate the external disadvantage of the falling distance information detecting mechanism, and has an excellent effect that the machining depth control can be more easily performed.

According to the substrate processing apparatus of the invention of claim 5 and the back-drilling processing method of the invention of claim 6, the processing depth of the back-drilling process for the substrate can be controlled at a low cost, accurately and precisely, and the processed substrate can be eliminated. The resulting noise and other undesirable conditions have an excellent effect of being able to manufacture the substrate itself at low cost.

According to the back-drilling method of the invention described in claim 7, the measurement error caused by the core deviation can be eliminated at low cost, and the excellent effect of the precise processing depth control can be performed more easily.

The back-drilling method of the invention described in claim 8 has an excellent effect of being able to continuously perform precise machining depth control.

A‧‧‧Substrate processing equipment

B‧‧‧Substrate processing equipment

C‧‧‧Substrate processing equipment

K‧‧‧Drop distance information testing agency

K1‧‧‧Drop distance information testing agency

K2‧‧‧Drop distance information testing agency

A‧‧‧ shaft

1‧‧‧Rotary body

2‧‧‧Rotor

3‧‧‧ drill bit

3-1‧‧‧ front end corner top

3-2‧‧‧ inclined section

4‧‧‧Detection device

5‧‧‧Bypass circuit

6‧‧‧High frequency oscillator

7‧‧‧Converter

7a‧‧‧Transformer

7b‧‧‧converter

8‧‧‧Detection circuit

9‧‧‧Detector

10‧‧‧Remove circuit

11‧‧‧ GND line

12‧‧‧ Output line

13‧‧‧Input winding

13a‧‧‧Input winding

14‧‧‧Removing the coil

15‧‧‧ iron core

16‧‧‧ Output winding

17-1‧‧‧ Analog Circuit

17-2‧‧‧ Analog Circuit

17-3‧‧‧ Analog Circuit

17-4‧‧‧ Analog Circuit

18‧‧‧Reverse bypass circuit

20‧‧‧ capacitor

21‧‧‧Double row component switch

22‧‧‧Three-phase motor

23‧‧‧U-phase winding

24‧‧‧V phase winding

25‧‧‧W phase winding

26‧‧‧Processing table

27‧‧‧Shell

28‧‧‧Inverter

29‧‧‧Cylinder

30‧‧‧Insulators

31‧‧‧Z-axis drive

32‧‧‧ Grounding

50‧‧‧ capacitor

51‧‧‧Double row component switch

52‧‧‧Simulated substrate circuit

101‧‧‧Substrate

102‧‧‧First built-in conductor layer

103‧‧‧First insulation

104‧‧‧Second insulation

105‧‧‧third insulation

106‧‧‧Second built-in conductor layer

107‧‧‧Surface conductor layer

108‧‧‧Surface conductor layer

109‧‧‧ Hole Department

109-1‧‧‧ Hole Department

109-2‧‧‧ Hole Department

110‧‧‧Electroplating Department

110-1‧‧‧Reserved error range

111‧‧‧ Lower board

112‧‧‧ Copper foil layer on the lower plate

201‧‧‧Area

202‧‧‧Sub-area

203‧‧‧Measurement point

301‧‧‧Aluminum board

302‧‧‧Bakelite board

V‧‧‧Commercial power supply

L‧‧‧Reactor

L ' ‧‧‧Reactor

R‧‧‧ impedance

R ' ‧‧‧ impedance

S‧‧‧CNC control circuit

S1‧‧‧record media

S2‧‧‧ extraction agency

S3‧‧‧ Calculation agency

q‧‧‧Booking thickness of the layer of the plating department

Θ‧‧‧ Angle of the front end angle of the drill bit

1 is a schematic view showing a configuration of a substrate processing apparatus including a processing depth control mechanism according to a first embodiment of the present invention; and FIG. 2 is a schematic view showing a configuration of a substrate as a detection target; 3 is a schematic view showing a division state of a region in which the lower plate is distinguished by an imaginary line; and FIG. 4 is a partially enlarged view showing a front end portion of the drill bit in the back drilling process of the first embodiment, and is a schematic display of the dimensional condition. Figure 5 is a further enlarged view of Figure 4; Figure 6 is a schematic view showing the dimensional condition of the back-drilling process of the second embodiment; Figure 7 is a partial enlarged view of Figure 6; In the substrate processing apparatus of the processing depth control mechanism shown in the third embodiment, in addition to the CNC control circuit, a schematic diagram of the circuit of the rotating shaft and the falling distance information detecting mechanism; and FIG. 9 shows the processing depth control mechanism shown in this embodiment. In the substrate processing apparatus, in addition to the CNC control circuit, a schematic diagram of the circuit of the rotation axis and the falling distance information detecting mechanism is shown.

SUMMARY OF THE INVENTION An object of the present invention is to improve the control accuracy of a machining depth at a low cost for back-drilling processing, and to minimize the amount of residuals in a perforation that may cause a problem such as noise. The present invention eliminates the error caused by the tilting or deflection of the processing table itself or the lower plate, and the error between the individual substrate itself and the design value by using the falling distance information detecting mechanism that detects the falling distance information by the drill bit itself. The influence is determined on the basis of the determination of the location and the measured value is substituted into a specific calculation formula to more accurately grasp the position of the ideal conductor layer, so as to achieve more accurate and precise control of the back-drilling process to the calculated machining. The purpose of the distance to the depth. The calculation formula is based on the relationship between the thickness position of the ideal conductor layer in the design of the substrate and the actual thickness position, and the relationship between the design thickness and the actual thickness of the substrate itself. There is a cognitive relationship between the relationships. In this way, in order to further improve the accuracy in the machining depth control, the position of the back-drilling process of the substrate is measured, and the back-drill is calculated at an individual height position of the lower plate position directly below the position where the back-drilling is performed. The thickness of the substrate at the processing position is sufficient, but this requires unnecessary time and cost. Therefore, the lower plate is divided into a certain individual regions, and the average value thereof is determined to calculate the thickness of the substrate. This is to balance time and cost with correctness.

Further, in order to prevent the occurrence of an error caused by the core deviation, the present invention is achieved by back-drilling the aluminum material on the substrate, and further, the aluminum substrate is continuously placed on the substrate. The problem of the back-drilling process can be eliminated by further loading the insulating upper plate on the aluminum upper plate.

Example 1

Fig. 1 is a schematic view showing a substrate processing apparatus A equipped with a falling distance information detecting mechanism K of an embodiment of the invention of the present application. a is a rotating shaft, and is provided on the upper side of the substrate 101 of the object to be detected, and is composed of a rotating shaft main body 1, a rotor 2, and a drill 3. The rotor 2 is relatively supported by a shaft bearing 1 by a ceramic bearing supported by the rotor 2 and used for back drilling. In addition, an air bearing can be used in the shaft instead of the ceramic bearing. A is a substrate processing apparatus that performs back drilling processing on the rotating shaft a. The falling distance information detecting means K (hereinafter referred to as detecting means K) of the rotating shaft a is a detecting means 4 for detecting the height position information of the substrate 101 as the detecting object with respect to the rotating shaft a, and is embodied by the circuit connecting the rotating shaft a. Further, in the present embodiment, only one rotating shaft a is shown, but the substrate processing apparatus is usually equipped with a plurality of rotating shafts for performing multiple simultaneous processing on the same substrate. Therefore, the number of the detecting devices 4 is configured to correspond to the number of the plurality of rotating shafts, and has the same number. However, the rotating shaft a is fixed to the cylinder 29 via the insulator 30, and the cylindrical body 29 is movable relative to the housing 27 by a driving device (not shown), so that the rotating shaft a itself is opposite to the substrate processing device A. The casing 27 is fixed so as to be movable in the X-axis direction (the horizontal direction on the paper surface). Further, in the Z-axis direction (up and down direction on the paper surface), the Z-axis driving device 31 is individually driven. On the other hand, in the Y-axis direction (depth direction on the paper surface), the processing table 26 is movable by a driving device (not shown), and is configured to move in conjunction with the substrate 101 fixed thereto. Further, the cylinder 29 is electrically connected to the casing 27, and the processing table 26 is also electrically connected to the casing 27 (the conduction relationship is shown by a broken line connection in Fig. 1).

Further, the rotating shaft a houses a three-phase motor 22 which is connected to each phase via a three-phase 200V commercial power source V and an inverter 28.

The rotating shaft a is connected to the casing via the bypass circuit 5 in the falling distance information detecting mechanism K, and has a relatively low resistance to the casing 27 with respect to the commercial frequency or the harmonic of the output voltage of the inverter 28, and is derived from the high frequency. The frequency of the current of the vibrator 6 is relatively high resistance. Since the rotor 2 of the rotating shaft a is relatively supported by the rotating shaft body 1 by the ceramic bearing, the respective rotating shaft body 1 and the rotor 2 are insulated. However, since the electrostatic capacitance CR exists between each of the rotating shaft main body 1 and the rotor 2, it can be said that it is electrically connected at a high frequency (again, in FIG. 1, the electrostatic capacitance CR is present, and it is shown that the capacitor between the rotating shaft main body 1 and the rotor 2 passes through the capacitor. Connected by a broken line, this description simply shows that the electrostatic capacitance CR exists between the rotating shaft main body 1 and the rotor 2, and in fact, there is not necessarily any connection or part). At the same time, there is a capacitance CS between the shaft main body 1 and the column body 29 (again, since the column body 29 is electrically connected to the casing 27, it has the same potential as the casing 27, and the capacitance CS is described in order to facilitate drawing. The shaft main body 1 and the casing 27 are respectively provided with electrostatic capacitances CU, CV, and CW between the shaft main body 1 and each of the motor winding wires 23, 24, and 25, and copper on the lower plate of the lower plate 111 to be described later. A capacitance S is also present between the foil layer 112 and the processing table 26.

On the other hand, the rotor 2 in the rotary shaft a is electrically connected to the drill 3. In addition, the housing 27 itself has a ground 32.

However, since the lower plate 111 itself is an insulator, it is electrically insulated from the surface of the processing table 26, but the upper surface of the lower plate 111 is coated with a copper foil to form a lower plate upper copper foil layer 112, which is generally the lower plate. Since the area of the upper copper foil layer 112 is large and the lower plate 111 is thin, the electrostatic capacitance CP between the copper foil layer 112 on the lower plate of the lower plate 111 and the processing table 26 is very large, and is turned on at a high frequency. .

Therefore, in the present embodiment, the lower plate 111 itself is an insulator made of a glass epoxy resin as described later, but the lower plate 111 itself may be made of an aluminum plate. In the case of the drop distance information detection of the drill bit, when the tip end of the drill bit 3 of the rotary shaft a contacts the object to be detected, for example, the surface conductor layer 107 of the substrate 101, it is generated only on the output winding 16 side of the converter 7. When the current is increased, the detector 9 detects a change in current and the case where the lower plate 111 itself is an insulator does not change.

The internal structure of the substrate 101 is as shown in detail in FIG. 2 and is a multilayer structure. However, in the present embodiment, for the sake of simplicity, the built-in conductor layer and the insulating layer are shown as two layers and three layers, and in fact, the substrate to be back-drilled has ten or more layers. The substrate 101 is composed of a layer of three insulating layers 103, 104, 105, surface and back conductor layers 107, 108, and a portion sandwiched between the first insulating layer 103 and the second insulating layer 104. An inner conductor layer 102 and a second inner conductor layer sandwiched between the second insulating layer 104 and the third insulating layer 105. The conductor layers 102, 106, 107, and 108 are all copper foils having a thickness of 12 to 25 μm. Further, each of the insulating layers 103, 104, and 105 is made of a thermoplastic resin, and each has a thickness of 50 to 100 μm. Further, a hole portion 109 through which the surface conductor layer 107 penetrates to the back surface conductor layer 108 is provided, and the inner peripheral surface thereof is a plated portion 110 which is plated with copper. The first inner conductor layer 102 is an ideal inner conductor layer, and the hole portion 109 is back-drilled to reach the very close vicinity of the first inner conductor layer 102. The back drilling process is a drill having a diameter larger than that of the hole portion 109 which is perforated, and is cut in the hole portion 109 of the hole to be in the vicinity of the surface of the surface conductor layer 107 to the first inner conductor layer 102. The copper plating portion of the plating portion 110 is intended to accurately and precisely control the processing depth.

Further, in the back drilling process, after the lower plate 111 is placed and fixed on the processing table 26, the substrate 101 is placed and fixed thereon. The lower plate 111 is a glass epoxy resin plate having a thickness of 1500 μm, and a lower plate upper copper foil layer 112 is provided on the upper plate. Further, a copper foil layer may be provided on the upper surface and the lower surface of the lower plate 111, or the lower plate 111 itself may be formed of an aluminum plate, but at least the upper surface of the lower plate 111 must be a conductor layer.

On the other hand, 4 is a detecting device composed of a high frequency oscillator 6, a converter 7, a detecting circuit 8 and a detector 9, and a bypass circuit 5 and a cancel circuit 10. The high frequency oscillator 6 is slightly 0.3W. The high frequency AC excitation of 0.5~2MHz is more suitable, but here it is excited at a high frequency of 1MHz. The high-frequency alternating current that is output is connected to the casing 27 via the GND line 11, and the output line 12 on the other hand is connected between the input winding 13 of the converter 7 and the eliminating winding 14. The current transformer 7 is the same number of times the two winding wires 13 and 14 are wound rightward from the side indicated by m, and the winding of the input winding wire 13 is completed at the start winding of the connection eliminating winding 14.

Further, both ends of the output winding 16 provided with the core 15 are connected to a detector circuit 8 composed of four diodes, and the detector circuit 8 is connected to the detector 9.

On the other hand, the bypass circuit 5 is configured to be in parallel with the reactor L and the impedance R, and one end of the circuit 5 The connection is at the beginning of the input winding 13 and the middle of the spindle body 1, and the other end is connected to the housing 27. The bypass circuit 5 is set to have a high impedance with respect to a high-frequency current from the high-frequency oscillator 6 for detecting the falling distance information, and is applied with respect to the inverter 28 that drives the commercial power source V to drive the rotating shaft a. The wave current has a low impedance, so the inductance of the reactor L is set in the range of 50 to 100 μH. If the inductance of the reactor L is less than 50 μH, the high-frequency current will flow to the bypass circuit 5 for detection, so that the contact of the drill bit 3 with the ideal conductor layer is difficult to detect correctly, and conversely, if it exceeds 100 μH, it comes from the inverter. The harmonic current of 28 or the like is also difficult to pass, and the grounding effect with respect to the rotating shaft a is lowered, so that it is difficult to maintain safety. In the present embodiment, the inductance of the reactor L is set such that the impedance component is slightly 0 Ω at 75 μH, and the impedance value of the impedance R is set to 200 Ω, and the inductance component is slightly 0 μH.

Further, the cancel circuit 10 is composed of four analog circuits 17-1, 17-2, 17-3, and 17-4 and an inverse bypass circuit 18. Each of the analog circuits 17-1, 17-2, 17-3, and 17-4 has eight capacitors 20 and eight double-row component switches 21 respectively arranged in series, and the capacitor 20 and the two-row component switch are arranged in series. 21 constitutes one group, and eight groups are arranged in parallel. These capacitors 20 have different capacities, and here are capacitors having capacities of 10 pF, 20 pF, 40 pF, 80 pF, 160 pF, 320 pF, 640 pF, and 1280 pF, respectively (again, the capacitor 20 and the double row of each analog circuit are omitted in FIG. The component switches 21 only display two groups each). One end of the analog circuit of 17-1 is connected to the end winding of the eliminating winding 14 of the current transformer 7, and the other end is connected to the casing 27. Further, one end of each of the analog circuits of 17-2 to 17-4 is connected to the U-phase, the V-phase, and the W-phase of the three-phase motor 22 housed in the spindle body 1, and the other end is connected to the elimination winding 14 of the converter 7. The end of the winding. Moreover, it is provided that the electrostatic capacitance of the analog circuit of 17-1 can be set to be slightly the same as the electrostatic capacitance CS between the rotating shaft main body 1 and the casing 27 by using the two-row component switch 21, and each of 17-2 to 17-4 The electrostatic capacitances of the analog circuits are set to be slightly the same as the electrostatic capacities CU, CW, and CV between the respective winding wires 23, 25, 24 of the three-phase motor 22 housed in the spindle body 1 and the spindle body 1. On the other hand, the object to be inspected is fixed to the processing table 26 of the substrate processing apparatus A, and the electrostatic capacitance CS between the rotating shaft main body 1 and the casing 27 and the phases of the three-phase motor 22 housed in the rotating shaft main body 1 are measured. After the capacitances CU, CV, and CW between the winding wires 23, 24, and 25 and the spindle body 1, eight eight-row component switches 21 of each of the analog circuits 17-1, 17-2, 17-3, and 17-4 are caused. Become in an appropriate energized state so that each has a slightly the same electrostatic capacitance. Further, each of the electrostatic capacitances CS, CU, CV, and CW is approximately 200 to 500 pF. However, since the ceramic bearing is used between the rotating shaft main body 1 and the rotor 2 in this embodiment, the electrostatic capacitance CR therebetween is slightly 200 pF, and the electrostatic capacitance CP between the copper foil layer 112 on the lower plate of the lower plate 111 and the processing table is It is about 500 to 1000 pF depending on the size of the substrate 101. Therefore, in the present embodiment, it is used to have a size of 1000 pF.

On the other hand, the reverse bypass circuit 18 is formed by connecting the reactor L ' identical to the bypass circuit 5 in the same manner as the impedance R ' , and the end of the circuit 18 is connected to the end winding of the canceling winding 14 of the current transformer 7. At the other end, the housing 27 is connected.

In the present configuration, since the non-detecting drill 3 is not in contact with the surface conductor layer 107 of the substrate 101 or the lower copper foil layer 112 of the lower plate 111, even if the motor winding wires 23, 24, 25 of the rotating shaft are applied from the opposite phase. The harmonic voltage of the device 28 also flows into the casing 27 via the bypass circuit 5. Therefore, the spindle main body 1 corresponds to the ground, and it is not necessary to provide safety measures corresponding to electric shock. Therefore, when the detection of the falling distance information is performed, even if the drill 3 contacts the surface conductor layer 107 of the substrate 101 or the lower copper foil layer 112 of the lower plate 111, no harmonic current flows to the drill bit 3 to damage the drill bit 3. The surface of the film or the like does not impair the life of the drill 3.

Further, the detection accuracy of the falling distance information has the following high accuracy. That is, in the non-detection, the current of the high-frequency voltage from the high-frequency oscillator 6 of the detecting device 4 flows into the input winding 13 of the converter 7, while the current flows through the respective electrostatic capacities CS, CU, CV, CW and the bypass circuit 5. The reactor L flows into the input winding wire 13, and the electrostatic capacitance generated by each of the analog substrates 17-1, 17-2, 17-3, and 17-4 of the eliminating circuit 10 is slightly equal to each electrostatic capacitance CS, respectively, by operating the switches 21 in advance. CU, CV, CW, therefore, each of the analog substrates 17-1, 17-2, 17-3, and 17-4 has an electrostatic capacitance slightly equal to each electrostatic capacitance, and is provided with a reverse bypass circuit 18 and the reverse bypass circuit 18 is provided with the same reactor L ' as the reactor L of the bypass circuit 5, so that a current slightly the same as the current flowing into the input winding 13 passes through the respective analog substrates 17-1, 17-2, 17- 3, 17-4 and the reactor L ' of the reverse bypass circuit 18 flow into the elimination winding 14. Therefore, the magnetic fluxes respectively occurring in the input winding 13 and the eliminating winding 14 cancel each other, so that the core 15 of the converter is not excited, and the output winding 16 has no output current flowing, so that the detector 9 does not erroneously detect the current change.

On the other hand, when the detection of the falling distance information is started, the Z-axis driving device 31 pushes down the rotating shaft a, for example, when the drill bit 3 contacts the surface conductor layer 107 of the substrate 101, it occurs via the rotating shaft body 1 and the rotor. Between the two, the electrostatic capacitance CR of the high-frequency oscillator 6 of the detecting device 4, and the upper surface of the lower plate 111 of the lower plate 111 which is formed by the plating portion 110 of the hole portion 109 of the substrate 101 from the surface conductor layer 107. The electrostatic capacitance CP between the foil layer 112 and the processing table 26 causes a high frequency current of slightly 1 MHz to flow into the drill bit 3, but since the current only flows through the input winding 13 without flowing through the elimination winding 14, the converter 7 The core 15 is excited by the new current to cause an output current to be generated on the output winding 16 side. Therefore, the change of the current is detected by the detector 9 via the detector circuit 8 composed of four diodes, and the rotation axis a is judged. The desired conductor layer of the drill bit 3 that contacts the substrate 101 is the surface conductor layer 107. Further, of course, when detecting the falling distance information, even if the drill 3 contacts the surface conductor layer 107 of the substrate 101, harmonic current does not flow to the drill 3 and damages the coating on the surface of the drill 3, so that the drill 3 is not damaged. Life expectancy.

In the case where the height position of the fixed substrate 101 placed on the lower plate 111 fixed to the processing table 26 is detected, the upper surface of the lower plate 111 is contacted with the lower surface of the lower plate 111 by the detecting bit 3 to detect the height thereof. In the case of position, since the object to be detected is different, the mechanism for correct detection is the same as described above.

Thus, by providing the eliminating circuit 10, the electrostatic capacitances CU, CV, CW between the winding wires 23, 24, 25 and the rotating shaft body 1 generated through the respective phases of the three-phase motor 22 are generated in the rotating shaft body 1 and the casing. The current flowing into the input winding 1 of the converter 7 with the electrostatic capacitance CS between the bodies 27 is slightly the same amount of current, and is eliminated by the setting of each of the analog circuits 17-1, 17-2, 17-3, and 17-4. The winding wire 14 and the current flowing into the input winding wire 13 via the reactor L of the bypass circuit 5 provided to prevent the harmonic current from flowing into the rotating shaft a drill 3 are also passed through the reverse bypass circuit by a similar amount of current. 18 flows into the elimination winding 14 so that the directions of the magnetic fluxes occurring in the input winding 13 and the current transformer 7 of the eliminating winding 14 cancel each other, so that the core 15 of the converter 7 is not excited, so that no output current flows. Output winding 16 . Thus, by canceling the magnetic flux generated by the current flowing into the input winding 13 of the current transformer 7, the external disadvantage of the output winding 16 side of the current transformer 7 before the detection of the falling distance information can be eliminated. Thereby, the drill bit 3 of the rotating shaft a has no contact with the ideal conductor, not the current change, but the electrostatic capacitance CR between the rotor 2 and the rotating shaft body 1 and the copper foil layer 112 on the lower plate of the lower plate 111 and the processing. It is easier to determine whether or not the series circuit of the electrostatic capacitance CP between the stages 26 has a signal of "1" or "0" through which the current passes.

Further, the detected falling distance information and the like are recorded or extracted in the CNC control circuit S of the substrate processing apparatus A in the following manner, and the back drilling processing can be accurately and precisely controlled via the respective calculation steps. depth.

That is, first, since the substrate 101 is manufactured with a certain design thickness, there is a substrate thickness L2d of its design. Further, in the perforation of the through-plane conductor layer 107 and the back conductor layer 108, the first inner conductor layer 102 is preferably a conductor layer, and the plating of the back surface conductor layer 108 and the first inner conductor layer 102 is left. When the back drilling process is performed to remove the unnecessary plating portion 110, the length from the surface conductor layer 107 to the first built-in conductor layer 102 which is an ideal conductor layer is referred to as a reference residual length L2d. When the substrate 101 is manufactured, the formation of the insulating layer and the conductor layer is predetermined. Therefore, the reference residual length Lnd can be obtained from the design value in the substrate 101 as long as the ideal conductor layer is first calibrated (see FIG. 4). ).

Although the plating portion 110 is cut by the back drilling process, when the length of the reserved error range 110-1 of the plating portion 110 is zero, it is the theoretical optimum.

On the other hand, as described above, the back surface conductor layer 108 and the ideal conductor layer, that is, the plating portion 110 of the first inner conductor layer 102 are left, and when the back plating process is performed to remove the unnecessary plating portion 110, anyway The machining error must occur, so the predetermined size td is determined as the predetermined error range in the design (see Fig. 4).

The values of the reference remaining length L2d and the length td of the design residual amount are recorded in the recording medium S1 of the CNC control circuit S.

Further, the predetermined thickness q of the layer of the plated portion 110 of the perforated hole portion 109 and the value of the angle θ of the tip end angle of the drill 3 are also recorded on the recording medium S1 of the CNC control circuit S.

Second, since the lower plate 111 is formed in a square shape when the backing processing is performed on the substrate 101, the imaginary line is divided into four equal parts in a state of being placed and fixed on the processing table 26, and the total is divided into a total of After the sixteen areas 201, the imaginary lines are divided into two equal divisions in the vertical and horizontal divisions to divide the total of four sub-areas 202 (see Fig. 3). The intersection of the individual diagonal lines of the sub-regions 202, that is, the center of each sub-region 202 is the measurement point 203 of the lower plate 111. That is, sixty-four measurement points 203 are set on the lower plate 111. Further, the measurement point 203 is a position which is the actual thickness of the measurement substrate 101 or a basic value when the actual position of the ideal conductor layer is calculated, and the measured value with respect to the lower plate 111 in the calculation described above is the average value. The value is therefore determined by a certain regularity and cannot be deviated on the lower plate 111. Generally, the lower plate 111 is a square shape of 33.5 cm × 50 cm in length and width. Therefore, the area 201 is its sixteenth division, and the sub-area 202 is also its four divisions. If the average value is used, it has been determined that there should be almost no error. However, depending on the size of the lower plate 111, it is considered to increase the number of divisions by appropriately adjusting the size of the area 201 and the sub-area 202.

Further, for example, when one hundred perforations are provided on one substrate 101 and back drilling is performed on the one hundred perforations, the individual measurement points 203 of the respective regions 201 are used here (four in one region 201 in the present embodiment) The average value of the measurement points 203) is determined. If the accuracy is prioritized over the economical efficiency, as described in the above-mentioned installation example, when the substrate 101 is placed and fixed on the lower plate 111 on the processing table 26, it should be calibrated. One hundred hole portions 109 of the back drilling processing position are respectively at positions corresponding to the lower plate 111, and the respective positions are used as the measurement points 203. However, in this method, it is necessary to calibrate the corresponding positions of one of the hundred hole portions 109 of the substrate 101 on the lower plate 111, which requires a cumbersome procedure, which causes an increase in time and cost. Here, the average value of the height position of the individual region 201 at the lower plate 111 is obtained, in order to achieve both rapidity, economy, and correctness. Therefore, it is necessary to consider the relationship between the size of the substrate 101, the size of the mother board from which the substrate is cut out, the number of the holes 110 to be back-drilled, and the correctness thereof, etc., so as to be appropriately determined. The number of regions 201 and sub-regions 202 of the board 111.

Next, it is determined that the specific position in the lower plate 111 is the origin (that is, the position in the vertical and horizontal XY coordinates is (0, 0)), and each of the regions 201 is given a number for identification, and the respective regions 201 are determined by coordinates. The range, and also the coordinate position of each measurement point 203 is also calibrated. As described above, in the present embodiment, four sub-regions 202 are provided in one region 201, and the measurement points 203 at the center of the sub-regions 202 are to be measured, so that there are four measurement points 203 in one region 201. For example, in the area 201 in which the identification number is set to No. 1, there are measurement points 203 of No. 1 to No. 4, and the measurement points 203 of No. 5 to No. 8 exist in the area 201 in which the identification number is set to No. 2. Therefore, the measurement points 203 existing in the area 201 are classified and recorded on the recording medium S1 of the CNC control circuit S for each of the above-described areas 201.

Third, in a state where the lower plate 111 is placed and fixed to the processing table 26, the height position of each of the measurement points 203 is measured using the falling distance information detecting means K of the substrate processing apparatus A. The upper surface of the lower plate 111 is formed as a lower plate copper foil layer 112. Therefore, if the front end of the drill 3 of the rotor 2 of the rotating shaft a contacts the copper foil layer 112 on the lower plate, the change in current is detected in the detector 9. Have contact. Moreover, the height position at the time point when the current change is detected is measured. This measurement operation is performed at all the measurement points 203, and the measurement result of each measurement point 203, that is, the height position information is automatically recorded in the recording medium S1 of the CNC control circuit S. On the other hand, in the calculation means S3 in the CNC control circuit S, the average value αave of the height position information of the measurement points 203 individually classified in the respective regions 201 is calculated, and the average value αave is also recorded in the recording medium S1 as the area. 201 height position information. For example, in the area 201 in which the identification number is set to be No. 1, there are measurement points 203 of No. 1 to No. 4, and thus the average value αave of the height position information of the measurement points 203 of the No. 1 to No. 4 is calculated, and recorded in the recording medium S1 as Height position information of area 201 in area 1. As a result, since there are sixteen regions 201 divided in this embodiment, there are regions 201 having identification numbers No. 1 to No. 16, and their respective average values αave are calculated. Further, the calculation of the average value αave of the height position information of the measurement point 203 by the individual region 201 may be calculated when the back-drilling processing depth L2c is calculated as will be described later.

Fourth, the XY coordinate position of each hole portion 109 of the substrate 101 is recorded on the recording medium S1 of the CNC control circuit S. For example, in one of the sheet substrates 101 in which one hundred perforated holes 109 are provided, the specific position of the substrate 101 is taken as the origin for the one hundred holes 109 (that is, the vertical and horizontal XY coordinates become (0, 0). Position)), the respective coordinate positions of the one hundred hole portions 109 are calibrated. For example, the coordinate position of the first hole portion 109-1 is (1, 1), and the coordinate position of the second hole portion 109-2 is (1, 2). Next, a number for identification is given to each of the one hundred hole portions 109, and the coordinate position is recorded on the recording medium S1 of the CNC control circuit S.

Fifthly, on the lower plate 111 placed on the processing table 26, it is further loaded and fixed for back drilling ( The processed substrate 101 is in the extraction mechanism S2 in the CNC control circuit S, and is located on the XY coordinate of each hole portion 109 subjected to back-drilling in this state, and the XY coordinates of each region 201 provided on the lower plate. At the position, the hole portions 109 corresponding to the respective regions 201 are extracted. At this time, if the position of the lower plate 111 as the origin is the position which is the origin of the substrate 101 and overlaps in the vertical direction when the lower substrate 111 is placed on the fixed substrate 101, the coordinate position of the hole 109 is compared. The coordinate position of the region 201 can be compared and extracted. If the positions of the origins of the two are different, the amount of deviation needs to be calculated, and the coordinate value of one of the coordinates is corrected, and the correspondence is compared and extracted. For example, if the position of the origin (0, 0) of the lower plate 111 overlaps with the position of the origin (0, 0) of the substrate 101 in the vertical direction, and the first region 201 is at (0, 0), ( When the coordinates of the squares of 4,0), (4,4), (0,4) are different, if the coordinate position of the first hole portion 109-1 of the substrate 101 is (2, 2), it is obvious that The hole portion 109-1 is present in the first region 201. However, if the position of the origin (0, 0) of the lower plate 111 is shifted by 10 in the X-axis direction with respect to the substrate 101, that is, the position of the origin (0, 0) of the lower plate 111 and the position of the substrate 101 (10, When the position of 0) overlaps in the vertical direction, the position of the origin of the plate 111 below the first region 201 is the (0, 0), (4, 0), (4, 4), (0, 4), the coordinates are converted to (10, 0), (14, 0), (14, 4), (10, 4) based on the position of the origin of the substrate 101. . As described above, since the coordinate position of the first hole portion 109-1 is based on the position of the origin of the substrate 101, and the coordinate position is (2, 2), the first hole portion 109-1 is not present on the lower plate. Within the first region 201 of 111. As described above, when there is a difference in the positions of the origins of the lower plate 111 and the substrate 101, it is of course necessary to have a measurement deviation and correct the coordinate value in accordance with the amount of deviation.

Sixth, the height position of each hole portion 109 of the substrate 101 to be mounted and fixed on the lower plate 111 fixed to the processing table 26 is measured using the falling distance information detecting means K of the substrate processing apparatus A.

Each of the hole portions 109 is formed from the front surface side to the back surface side of the substrate 101, and the inner peripheral surface thereof is the plating portion 110, and the surface conductor layer 107 is present around the plating portion 110 on the front surface side. Therefore, if the rotor of the rotating shaft a is present, The tip end of the drill bit 3 of 2 contacts the plating portion 110 and the surface conductor layer 107, and the detector 9 detects a change in current and determines that there is contact. When the current change is detected, the height position is measured. This measurement operation is performed in all the hole portions 109, and the measurement results of the individual hole portions 109, that is, the height position information, are automatically recorded in the recording medium S1 of the CNC control circuit S with the respective hole portions 109.

Seventh, according to the correspondence between the respective regions 201 of the lower plate 111 and the hole portion 109 of the substrate 101, the calculation mechanism S3 of the CNC control circuit S is measured from the sixth The height of each hole portion 109 is subtracted from the average height αave of the region 201 of the lower plate 111 corresponding to the hole portion 109 calculated in the third embodiment, and the subtracted value is used as the hole portion 109 on the substrate. The actual thickness of 101 is automatically recorded on the recording medium S1 of the CNC control circuit S. For example, generally, the position of the origin (0, 0) of the lower plate 111 overlaps with the position of the origin (0, 0) of the substrate 101 in the vertical direction, and the first region 201 is at (0, 0), When the coordinates of the squares (4, 0), (4, 4), (0, 4) are different, if the coordinate position of the first hole portion 109-1 of the substrate 101 is (2, 2), the hole Since the portion 109-1 is present in the first region 201, the height position value measured from the first hole portion 109-1 is subtracted from the average value αave of the height of the first region 201, and the deducted value is taken as the first The thickness of the substrate 101 at the position of the hole portion 109-1 is recorded on the recording medium S1 of the CNC control circuit S. This calculation is also performed for all of the hole portions 109. Further, this calculation is the same as the calculation of the average value αave of the height position information of the region 201 described in the third embodiment, and may be calculated when the back-drilling processing depth L2c is calculated as will be described later.

According to the calculation formula of the average value of the height positions of the respective regions 201 of the lower plate 111 from the values of the height positions of the positions of the respective hole portions 109, the inclination or deflection existing in the processing table 26 itself can be eliminated, and There are various factors that cause the height position of the lower plate to be deviated due to the inclination or deflection of the lower plate 111 itself, so that maintenance or fine fine adjustment for solving the level or deflection of the processing table 26 can be omitted. The procedure does not require the precision of the thickness of the lower plate 111 itself. In particular, the inclination or deflection of the processing table 26 is generally shown to be an error of ±50 μm in the processing range of the substrate 101, and the lower plate 111 placed thereon is also inclined or deflected so that the lower plate is present. The error caused by the manufacture of the 111 itself exists. Therefore, the error of the processing table 26 itself and the error accumulated by the lower plate 111 itself may become a large amount of error in the depth control of the conventional back drilling process. The cause. However, in the present embodiment, since the calculation formula of the average value of the height positions of the respective regions 201 of the lower plate 111 is deducted by applying the height position value from the position of each hole portion 109 as described above, the lower plate 111 and the substrate The error of about ±5 μm of the respective height positions of 101 (actually, each hole portion 109 of the substrate 101), that is, the measurement error caused by the falling distance information detecting mechanism K using the drill 3 is difficult to avoid, but it may be The error between the two is included in the range of the error of a total of ±10 μm.

As a result, it is possible to not only reduce the error of the machining depth control during the back drilling process, but also to perform the maintenance work of precisely correcting the inclination or deflection of the surface of the machining table 26 or the fine adjustment procedure.

Eighth, in the calculation mechanism S3 of the CNC control circuit S, the following calculation is performed individually for each hole portion 109, and the individual back-drilling depth L2c is calculated.

L2c=Lnd×(L2m-αave)/L2d-td+corner tan1

Lnd=Design base length

The value of L2m-αave is calculated and recorded in the aforementioned seventh step.

L2d=the thickness of the substrate 101 on the design

Td=the length of the design's reserved error range

The angle tan1 = the thickness of the layer of the plated portion 110 provided in the perforated hole portion 109, q × tan {(180 degrees - the angle θ of the tip end angle of the drill bit 3) ÷ 2}

In this calculation formula, the ratio of the thickness of the designed substrate 101 to the actual thickness of the substrate 101 at the position of each hole portion 109 for back-drilling is calculated by (L2m - αave) / L2d. On the other hand, since the ideal conductor layer, that is, the height position of the first built-in conductor layer 102 in the substrate 101, is determined at the time of design, the surface of the substrate 101 reaches the first built-in conductor layer 102. The distance is of course determined at the time of design. The distance on this design is the reference residual length Lnd. Moreover, the ratio of the thickness L2d of the substrate 101 itself to the actual thickness L2m-αave of the substrate 101 in each of the holes 109 is known, and the ideal conductor layer is also designed in the substrate 101 of the first built-in conductor layer 102. The height position, that is, the reference remaining length Lnd, is obtained from the surface of the substrate 101 to the first interior after subtracting the actual height position of the first built-in conductor layer 102 from the hole portion 109 at the actual height position of the substrate 101. The ratio of the actual distances up to the conductor layer 102 has an equal relationship between the two ratios. Therefore, the reference substrate length Lnd is multiplied by the above-described (L2m-αave)/L2d equation, and the designed substrate 101 thickness L2d and the position of each hole portion 109 subjected to the back-drilling process are actually the substrate 101. The ratio of the thicknesses is used to calculate the actual conductor layer, that is, the actual height position of the first inner conductor layer 102 in the substrate 101, that is, the actual length of the excess length portion.

As described above, αave is a numerical value representing the average height of the region 201 of the lower plate 111 in which the respective hole portions 109 exist. Therefore, although it is not completely precise, it is considered to be economical or rapid, and it is compared with each hole portion. 109 Measure and calculate the height position of the corresponding position on the lower plate 111, which can be said to be more reasonable, use the concept of the area 201 to calculate the average value, or at all, can be regarded as the measurement accuracy problem, the foregoing calculation It is also impossible for the actual distance from the surface of the substrate 101 to the ideal conductor layer in the hole portion 109 to be completely free of errors. Therefore, although it is necessary to retain a certain margin of error as a safety factor, as in the present embodiment, the objective actual distance from the surface of the substrate 101 to the ideal conductor layer in the hole portion 109, and the calculated Between the distances, as long as the error is small, a lower safety factor can be considered, that is, the length of the residual amount is set to be shorter. In this sense, the predetermined residual amount is referred to as the reference residual amount td, and the reference residual amount td is subtracted from the calculated actual distance from the surface of the substrate 101 to the ideal conductor layer in the hole portion 109 thus calculated.

However, the drill bit 3 subjected to the back drilling process has a front end angle θ which is formed with a front end corner top 3-1. Therefore, in order to measure the height position of the substrate 101 at the position where the perforation is provided and the drill 3 is lowered, the tip end angle 3-1 of the drill bit 3 advances into the hole portion 109 by extending to the surface side of the substrate 101. The inner side of the plated portion 110 contacts the inclined portion 3-2 so that the contact between the front end of the drill 3 and the substrate 101 is measured by the falling distance information detecting means K. That is, at this point in time, the front end top 3-1 of the drill bit 3 actually reaches a position lower than the height position of the substrate 101. On the other hand, in the back drilling process, the front end of the drill bit 3 travels to the perforated hole portion 109 to perform the cutting of the plating portion 110, but the cutting portion 3 of the drill 3 is the inclined portion 3-2 instead of the front end corner portion thereof. 3-1, therefore, not only the position of the top end 3-1 of the front end of the drill bit 3 but also the position of the inclined portion 3-2 of the drill bit 3 which determines the length of the reserved error range 110-1 of the excess length portion The deviation, and the upper end portion of the marginal error range 110-1, is cut to be inclined with respect to the hole portion 109, and the outer side is long and the inner side is short (see Fig. 5). On the other hand, the length td of the design reserved error range is determined to be the longer front end portion with respect to the hole portion 109 of the reserved error range 110-1, and therefore, the reserved error range is 110-1. The deviation between the inner side and the outer side of the plated portion 110 can be corrected by calculating the angle tan1 with respect to the thickness of the plated portion 110. That is, by calculating the value calculated by the thickness of the layer of the perforated plated portion 110 × tan {(180 degrees - the angle of the front end angle θ of the drill bit) ÷ 2}, the calculation is corrected to correctly and precisely back Control of the machining depth of the drilling process.

As a result, the height position of the surface of the substrate 101 in the hole portion 109 is measured with the origin of the rotor 3 of the rotor 2 of the rotating shaft a not contacting the substrate 101 as the origin in the height direction, and thus the displacement distance of the drill bit 3 is detected. When the distance to the surface of the substrate 101 is equal to the distance after the machining depth L2c of the back drilling process is completed, the back drilling process is stopped, and the back drilling process can be performed at a correct depth.

In this way, each step of recording, extraction, calculation, and the like is automatically performed in the CNC control circuit S, and the machining depth for back drilling processing for each of the hole portions 109 can be continuously and accurately controlled in a short time.

Moreover, the order of the foregoing steps is only an example, and of course, the steps having a logical relationship, for example, the calculation in the eighth step needs to record or extract the values used in the calculation in advance, and the order relationship thereof is limited. Conversely, as in the first step and the second step, the steps that are not logically related to each other are not limited by the step relationship described in the embodiment, and the order relationship may be exchanged.

As described above, the substrate processing apparatus A of the present embodiment has the drill bit 3 itself having the falling distance information detecting mechanism K capable of detecting the falling distance information, and has the CNC including the recording medium S1, the extracting mechanism S2, and the calculating mechanism S3. The control circuit S calculates the machining depth of the back drilling process according to the above formula based on the height position information of the lower plate 111 or the substrate 101 measured by the drill 3. Furthermore, by using the back-drilling method of the present embodiment, the back-drilling process can be performed by correctly and precisely controlling the machining distance of the drill bit 3 of the rotary shaft a according to the calculated machining depth, thereby being quick and economical. Further, the hole portions 109 which are subjected to the back drilling process are precisely subjected to the back drilling process in the actual thickness of the substrate 101 and the actual distance from the surface of the substrate 101 to the ideal conductor layer. Further, as a result, the length td of the design reserved error range can be minimized, and the processed substrate 101 with low cost and less occurrence of noise such as noise can be provided.

Therefore, as described in the seventh step, an error of about ±10 μm as the measurement error is difficult to avoid, and the individual deviation of the region 201 and the thermal displacement of the substrate 101 during processing are also causes of errors, and even considering In this embodiment, it is also possible to maintain the length of the correction error range of the machining depth of the back-drilling processing within the range of the error of ±40 μm. Therefore, one hundred perforations were provided in the following experimental substrate, and the substrate processing apparatus A of the present embodiment was used to perform back drilling processing on the one hundred perforated hole portions in accordance with the method shown in this embodiment. Thereafter, each of the hole portions was cut out from the test body, and the length of the actual reserved error range was measured under a microscope, and compared with the length of the reference reserved error range, the difference was found to be within ±25 μm.

Experiment body and settings

Aspect: 33.5cm × 50cm

Insulating layer: a three-layer structure made of a glass epoxy resin of a thermoplastic resin (first to third insulating layers from the back side), respectively, a thickness of 75 μm of a conductor layer: using a copper foil on the surface of the test body And a back surface, and a first inner conductor layer is disposed between the first insulating layer and the second insulating layer, and a second inner conductor layer is disposed between the second insulating layer and the third insulating layer, and the thickness of each is 20 μm

Lnd: 170μm

L2d: 265μm

Td: 50μm

Thickness of the layer of the perforated plated portion: 40 μm

Tip angle of the drill bit: 130 degrees

Lower board content

Vertical and horizontal thickness: 33.5cm × 50cm × 1.5mm

Material: Glass epoxy

Thickness of copper foil layer on the lower plate: 20μm

Example 2

6 shows that, in the back drilling process, when the fixed substrate 101 is placed on the processing table 26 with the lower plate 111 interposed therebetween, the aluminum upper plate 301 having a known thickness is placed on the substrate 101 and mounted thereon. A state in which a bakelite bakelite plate 302 is fixed.

In the embodiment in which the upper plates 301 and 302 are used as described above, the measurement and calculation formula of the control of the machining depth for performing the back drilling process differs in the following points.

That is, first, although the aluminum upper plate 301 is electrically conductive, since the bakelite upper plate 302 is insulative, the lower plate 111 is placed on the processing table 26, and after the fixed substrate 101 is placed thereon, In the state in which the aluminum upper plate 301 and the bakelite upper plate 302 are fixed and placed thereon, the position of the XY coordinates corresponding to the respective hole portions 109 of the substrate 101 is detected by the lowering distance information detecting means K using the drill 3 in the aluminum material. The height position of the upper plate 301 is L2m1. That is, in the first embodiment, instead of detecting the height position of each hole portion 109 of the substrate 101 fixed on the lower plate 111, the falling distance information detecting mechanism K is used, and the XY coordinate position of each of the hole portions 109 is used. In the state where the aluminum plate upper plate 301 is placed and fixed on the substrate 101, the height position corresponding to the XY coordinate position of each hole portion 109 is measured. At this time, since the bakelite upper plate 302 is non-conductive, even if the drill bit 3 contacts the bakelite upper plate 302, the falling distance information detecting mechanism K does not detect its position information, but at the top end of the drill bit 3 When the 3-1 is in contact with the aluminum upper plate 301, the falling distance information detecting mechanism K detects the position information. On the other hand, this height position replaces the height position of each hole portion 109 of the substrate 101 on the lower plate 111 fixed to the processing table 26 in the first embodiment, and is used in the calculation formula. The correspondence between the measurement position on the aluminum upper plate 301 and the area 201 of the lower plate 111, and the average height of the lower portion 111 of the region 201 having the corresponding relationship are obtained, and the same as in the first embodiment.

Secondly, in the present embodiment, since the height position of each hole portion 109 of the substrate 101 is not measured, the height position L2m1 of the XY coordinate position corresponding to each hole portion 109 of the substrate 101 in the aluminum upper plate 301 is Therefore, when calculating the thickness of the substrate 101, it is necessary to subtract the thickness of the aluminum upper plate 301, and the thickness of the substrate 101 can be calculated according to the calculation formula of L2m1-αave-tAL. Further, tAL is the thickness of the aluminum upper plate 301, which is set at the time of design as will be described later.

Third, regarding the ratio of the measured thickness from the substrate 101 to the thickness of the design, the length of the actual excess length portion is calculated based on the reference residual length existing in the design of the ideal conductor layer, and the design reservation is deducted. The length td of the error range is used to calculate the machining depth L2c of the back drilling process. Here, in addition to the thickness of the aluminum upper plate 301, the front end angle of the drill bit 3 generated by the front end angle θ of the drill bit 3 must be added. The position of the top 3-1 is different from the height position between the inclined portion 3-2 of the drill 3 and the plating portion 110 provided in the hole portion 109 (hereinafter, this distance is referred to as "angle tan2").

That is, before the start of the back-drilling process, the distance from the position of the drill shaft 3 of the rotary shaft a to the position of the origin (the position at which the Z of the height is zero) to the aluminum upper plate 301 is P, The distance P is a fixed lower plate 111 placed on the processing table 26, and after the fixed substrate 101 is placed thereon, and the aluminum upper plate 301 is placed thereon, the top end of the drill 3 is 3-1. When the aluminum upper plate 301 is touched, it is detected by the falling distance information detecting mechanism K. At this point, the tip end angle 3-1 of the drill bit 3 is at the same height position as the height position of the aluminum upper plate 301. In the back drilling process, although the tip end of the drill bit 3 travels in the perforated hole portion 109 to perform the cutting of the plating portion 110, the drill portion 3 has the inclined portion 3-2 at the cutting plating portion 110 instead of the front end corner thereof. 3-1, therefore, not only the position of the front end 3-1 of the front end of the drill bit 3 but also the position of the inclined portion 3-2 of the drill bit 3 of the remaining error portion 110-1 of the remaining length portion may be deviated. The upper end portion of the error range 110-1 is obliquely cut to be longer with respect to the outer side of the hole portion 109 and shorter for the inner side. On the other hand, the length td of the design-predetermined error range is determined by the front end portion of the predetermined error range 110-1 with respect to the outer side of the hole portion 109, and therefore, the tip end angle 3 of the drill bit 3 The deviation between the position of -1 and the height of the outer side of the plating portion 110 which becomes the reserved error range 110-1 can be calculated by calculating the radius of the perforation with respect to the processing for performing the perforation (adding the radius of the hole portion 109 and plating The thickness of the portion 110 is increased by the angle tan2 (see Fig. 7).

In other words, as described in Embodiment 1, the upper end portion of the predetermined error range 110-1 of the plating portion 110 is inclined to be longer than the outer side of the hole portion 109, and the inner side is shorter, and therefore, the design error is reserved. The length td of the range is measured by the position of the front end of the hole portion 109 on the outer side. In this way, the value of the length of the actual residual length calculated from the calculation formula of Lnd×(L2m1−αave−tAL)/L2d based on the measured value is subtracted from the length td of the design reserved error range. The representative plating portion 110 is subjected to the back-drilling distance, but since the tip end angle top portion 3-1 of the drill bit 3 contacts the aluminum upper plate 301, it is not the distance at which the drill bit 3 actually has to move until the end of the back-drilling process. In order to calculate the distance that the drill bit 3 must actually move, it is necessary to correct the position of the tip end angle 3-1 of the drill bit 3, and the position of the plating portion 110 in contact with the inclined portion 3-2 of the drill bit 3 (as described above, the margin of error) The length of 110-1 is measured at a position on the outer side with respect to the hole portion 109, that is, the position outside the plated portion 110 which becomes the reserved error range 110-1, and must be added by the following calculation formula. The value of this value (this value is the angle tan2).

Angle tan2=β×tan{(180 degrees - angle θ of the tip angle of the drill bit)÷2}

β = the radius of the perforation during the processing of the perforation (the radius of the hole portion 109 and the thickness of the plating portion 110). As a result, the respective machining depths L2c of the hole portions 109 in the back drilling process can be calculated by the following formula To calculate.

L2c=Lnd×(L2m1-αave-tAL)/L2d-td+tAL+corner tan2 Lnd=Design base length

L2m1=on the substrate 101 placed on the lower plate 111 of the processing table 26, and further, the aluminum plate upper plate 301 having a known thickness is placed and fixed, and the individual regions 201 existing as the lower plate 111 are extracted. Measured height of each back-drilling machining position of the coordinate range

Aveave = the average of the measured heights of the individual measurement points 203 in the lower plate 111 on the processing table 26

L2d=the thickness of the substrate 101 on the design

Td=the length of the design's reserved error range

tAL=thickness of aluminum upper plate 301

In this case, the thickness of the aluminum plate used as the aluminum upper plate 301 may be as long as it is known, but the convenience in use and the error range of the thickness of the aluminum upper plate 301 itself may be considered, and the thickness is used. About 0.15mm is more appropriate. At this time, although the deviation of the thickness may cause an error of about ±10 μm, since the aluminum plate 301 is not used, the center line of the hole portion 109 for performing the back drilling process and the drill bit 3 for performing the back drilling process must be performed. The center line is precisely consistent, and strong support is required in the back-drilling process to prevent the core 3 from deviating due to skewing, so consider the required procedure and the back caused by the deviation of the two centerlines or the core deviation. It is meaningful to use the aluminum upper plate 301 to prevent the error caused by the deviation of the center line from occurring in the machining depth of the drilling process.

On the other hand, the hole portion 109 having the plating portion 110 is back-drilled by the drill 3, and the plating portion 110 is cut by the drill 3 to generate specific linear chips. When the aluminum plate upper plate 301 is placed on the substrate 101 and the linear chip is attached to the front end of the drill bit 3 in contact with the aluminum upper plate 301, the lower distance information detecting mechanism K detects the next perforated hole portion. When the distance information of 109 is reduced, this linear chip will become an external defect and hinder the detection of the falling distance information. Therefore, the chips adhering to the tip end of the drill 3 are often removed. However, when a large number of back-drilling processes are continuously performed on a plurality of substrates, the time and procedure required for removing the chips increase the cost of the substrate processing. Therefore, the method of removing the linear chips adhering to the tip end of the drill 3 in a simple and rapid manner is to load and fix the bakelite upper plate 302 of the bakelite on the aluminum upper plate 301 during the back drilling process. Thereby, when the leading end of the drill bit 3 is to detect the falling distance information of the next perforated hole portion 109 in a state in which the wire-like chips are attached, first, the front end of the drill bit 3 is in contact with the bakelite upper plate 302 to perform the bakelite upper plate 302. Since the perforations are formed, the chips of the bakelite plate 302 which is the insulator are pushed away by the linear chips which adhere to the plated portion 110 at the tip end of the drill 3. Thereby, the drop distance information can be continuously detected on the perforated hole portion 109 without using a special removal means.

Incidentally, for the present embodiment using the aluminum upper plate 301 (thickness 0.15 mm) and the bakelite upper plate 302 (thickness 1 mm), the same experimental body and conditions as in the first embodiment were used, and one hundred perforations were used. The hole is drilled back. Thereafter, each of the hole portions was cut out from the test body, and the length of the actual reserved error range was measured under a microscope, and compared with the length of the reference reserved error range, the difference was found to be within ±25 μm.

Example 3

However, in the first embodiment, in the first embodiment, in order to remove the external defect factor when the detector 9 detects a change in current, the cancel circuit 10 or the bypass circuit 5 may be provided. In a more simplified configuration, the falling distance information detecting means K1 is formed by the high frequency oscillator 6, the current transformer 7a, the detecting circuit 8, the detector 9, and the bypass circuit. That is, as shown in Fig. 8, the GDN line 11 is connected from the high frequency oscillator 6 as a high frequency power source to the casing 27 of the substrate processing apparatus B, while the output line 12 is connected to one end of the input winding 3 of the converter 7a, And the other end of the input winding wire 13 is connected to the spindle body 1. The input winding 3 of the converter 7a is connected to the middle of the spindle body 1, and a bypass circuit 5 is provided. That is, in the falling distance information detecting means K shown in the first embodiment, the structure in which the portion of the eliminating circuit 10 is eliminated is omitted. Therefore, although the current transformer uses the current transformer 7a which does not have the winding wire 14, it is only This is different.

In the embodiment, the falling distance information detecting means K1 does not itself exclude the function of the external bad factor. Therefore, if the bearing used between the rotating shaft main body 1 and the rotor 2 is an air bearing, the electrostatic capacity CR between the rotating shaft main body 1 and the rotor 2 can be sufficiently allowed to be 1000 pF or more, and the front end of the drill bit is in contact with the surface conductor layer. When the accuracy is lowered, or the current of the filter element flowing to the input winding of the converter is limited to the current of the specific frequency from the high frequency oscillator, the falling distance information detecting mechanism K1 can be reduced by a simple configuration. cost. Further, by providing the bypass circuit 5 between the connection housings 27 in the middle of the connection line connecting the input winding 13 of the current transformer 7a and the spindle body 1, the rotation shaft a can no longer be a so-called floating metal, and it is not necessary to prevent it. Protection against electric shock. Further, by this, a current such as a harmonic current can be further flown to the casing 27 via the drill 3, and the metal surface of the drill 3 or the surface of the drill 3 due to the current can be prevented from being damaged, and the drill can be used for a long period of time.

Further, at least the falling distance information detecting means K1 in the embodiment is the conventional falling distance information detecting means K1. Therefore, even if the falling distance information detecting means K1 is used, the article described in the first embodiment can be installed. The CNC control circuit S of the extraction and calculation mechanism configures the conventional substrate processing apparatus as a substrate processing apparatus that can accurately and precisely control the processing depth of the back-drilling process.

Further, if a mechanism for preventing electric shock or a damage of the drill is not required, it is also conceivable to use a falling distance information detecting mechanism that further omits the bypass circuit 5.

Example 4

Figure 9 shows Example 4. With respect to the first embodiment shown in FIG. 1, the rotating shaft 1 is insulated from the cylinder 29 (the same potential as the housing 27), so that the substrate 101 can be insulated or uninsulated relative to the processing table 26, this embodiment is The rotating shaft 1 is directly mounted in a state of being uninsulated by a cylinder (not shown) which is not shown, so that the substrate 101 is placed on the processing table 26 in a state of being insulated from the processing table 26. In the present embodiment, since the lower plate 111 for insulation is used, the lower plate 111 made of aluminum cannot be used.

As shown in FIG. 9, the falling distance information detecting means K2 in the present embodiment has a dummy substrate circuit 52 in which a capacitor 50 and a two-row unit switch 51 arranged in series are arranged in a group, and a capacitor of the complex array is arranged in parallel with the switch. . That is, the substrate 101 as the object to be inspected is insulated from the casing 27 of the substrate processing apparatus C, and is formed on the processing table 26 in the casing 27 under the glass epoxy resin having the copper foil layer 112 on the lower plate. After the board 111 is insulated and fixed, the housing 27 is connected from the GND line 11 on one side of the high frequency oscillator 6 while the one side terminal of the analog board circuit 52 is connected, and the output line 12 on the other side is connected by the converter. The two input winding wires 13 and 13a of the device 7b are in the same direction and the end winding of the same number of coils, and the input winding wires 13 and 13a are in the same winding direction as the number of coils. In the coil, when the respective input winding wires 13, 13a have the same amount of current, the directions of the magnetic fluxes occurring in the core 15 of the current transformer 7b cancel each other, so that no current is generated on the output winding 16 side. Further, the other end of each of the two input winding wires 13 and 13a of the current transformer 7b is a surface conductor layer 107 on which one side of the substrate 101 as a detection target is connected, and the other side is connected to the other side of the analog substrate circuit 52. Terminal. By adjusting the two-row unit switch 51 of the analog substrate circuit 52, the electrostatic capacitance between the surface conductor layer 107 and the casing 27 of the substrate 101 as the object to be detected is substantially equal, so that the input winding wires 13 and 13a are provided. When the same amount of current flows, the directions of the magnetic fluxes generated in the current transformer 7a cancel each other out, so that the detector 9 can detect the contact between the front end of the drill shaft 3 of the rotary shaft a and the surface conductor layer 107 of the substrate 101 as the object to be detected. The change in the generated current becomes a falling distance information detecting means K2 as a change in the current output from the current transformer 7a.

The falling distance information detecting means K2 shown in the fourth embodiment can eliminate the external defect factor when detecting the falling distance information, and can use the same as in the case of the third embodiment when it is provided in a known substrate processing apparatus. The distance information detecting means K2 is provided with a CNC control circuit S having the memory, extraction, and calculation means described in the first embodiment, and the conventional substrate processing apparatus is configured as a substrate which can accurately and precisely control the processing depth of the back drilling process. Processing device.

In the invention of the present application, a substrate processing apparatus having a falling distance information detecting mechanism and a method of using the substrate processing apparatus can prevent the thickness of the substrate itself from being performed by back drilling of the substrate. Error or deflection, or the error of the machining depth due to the error of the thickness of the lower plate, such as the inclination or deflection of the processing table itself of the substrate processing apparatus, can be accurately and precisely controlled Further, since the length of the design error range can be set to be short, it is possible to achieve a low-cost substrate for preventing the occurrence of noise, and the like, in addition to the back-drilling process, In the processing of opening the substrate to a certain depth, the processing depth can be accurately and precisely controlled.

Claims (8)

 A processing depth control mechanism is a substrate processing apparatus capable of back-drilling a multilayer printed wiring board using a computer, and controlling a falling distance of a drill bit of the rotating shaft during back drilling processing, the processing depth control mechanism having a falling distance information detection The mechanism is configured to detect the falling distance information by contacting the detecting object with the rotating shaft, and includes a recording medium, an extracting means, and a calculating means for recording the position information and the like described in the following 1 to 5: 1. Numerical information on the thickness of the substrate on the design, the length of the reference and the length of the design tolerance (residual amount), and the predetermined thickness of the layer of the plating layer provided in the hole portion of the perforation and the angle of the tip angle of the drill bit 2. The measurement is performed on the processing table of the substrate processing apparatus, and at least the upper surface is configured as a lower layer of the conductor layer, and the measurement point determined by the following setting and the coordinate position information of each area on the plane are determined. The point is: a grid-shaped area that divides a plurality of areas, a unit of each area, and a measurement point determined by the same reference, or In each of the regions, each of the regions is further divided into a lattice-shaped sub-region on the same basis, and one measurement point determined by each sub-region and on the same basis; 3. For each of the above-mentioned measurement points, The height position information of each measurement point measured by the lowering distance information detecting means is lowered by the rotation shaft provided by the drill bit for performing the back drilling processing; 4. The present invention is present on the processing table placed on the substrate processing apparatus. The position of the back-drilling processing position on the plane on the multilayer printed wiring board on the lower board or the mother board (hereinafter simply referred to as "master board") which is present in front of the plurality of printed wiring boards. 5. The height position information of each of the back drilling processing positions measured by the descending distance information detecting mechanism by lowering the rotating shaft to the back drilling processing position of the substrate or the mother board; The individual coordinate position information of each of the above regions, and the coordinate position information of the back drilling processing position existing on the multilayer printed wiring board or the mother board thereof, and extracting the back drill In the state in which the multilayer printed wiring board or the mother board is placed on the lower plate during processing, the back drilling processing position exists in each coordinate range of each region of the lower plate; the calculation means automatically calculates according to the following formula The individual back drilling processing depth L2c, automatic control of the processing depth of the back drilling processing in the substrate processing apparatus: L2c = Lnd × (L2m - αave) / L2d - td + angle tan1; Lnd = design basis excess length; L2m = extraction load The multilayer printed wiring substrate or its mother board placed on the lower plate on the processing table, the measured height of each back-drilling processing position in the individual coordinate range of each region existing in the lower plate; αave=on the processing table The average of the measured heights of the measurement points of the individual regions in the lower plate; L2d = the thickness of the multilayer printed wiring substrate on the design; td = the length of the design tolerance range; the angle tan1 = the layer of the perforated plating portion The predetermined thickness × tan {(180 degrees - the angle of the front end angle of the drill bit) ÷ 2}.    The processing depth control mechanism according to claim 1, wherein the falling distance information detecting mechanism has at least a high frequency alternating current power source, a bypass circuit with a reactor, and a high frequency converter, and the output of the high frequency alternating current power source One side is connected to the housing, and the other side is connected to the rotating shaft insulated from the housing via the converter, and between the connection with the rotating shaft, a bypass circuit connecting housing with a reactor is provided, by the rotating shaft The drill bit of the rotor contacts the object to be detected by the conductor, and the high-frequency current from the high-frequency AC power source flows into the rotating shaft through the converter, and flows into the high-frequency AC power source via the capacitance between the conductor and the conductor layer. The output side generates a current, and by detecting a change in the current by the detector, it is configured as a falling distance information detecting means that can recognize the falling distance information of the drill bit.    The processing depth control mechanism according to claim 1, wherein the falling distance information detecting mechanism has a high frequency alternating current power source, a bypass circuit with a reactor, a eliminating circuit, and an input winding, a winding wire, and one or more output winding wires. In the high-frequency current transformer, the input winding wire and the eliminating winding wire are the same number of coils but the winding direction is opposite, and the eliminating circuit has an inverse bypass circuit and a plurality of analog circuits, and the reverse bypass circuit has a bypass circuit a reactor of the same electrostatic capacity, and each set of analog circuits is formed by a capacitor and a switch arranged in series, and the capacitor of the complex array is arranged in parallel with the switch as an analog circuit, and is insulated from the casing. When the rotating shaft is energized, the analog circuits of the sets respectively correspond to the respective electrostatic capacitances between the winding wire and the rotating shaft body of each phase of the motor that generates the rotating shaft, and between the rotating shaft body and the housing, and the reverse bypass circuit and the plurality of sets The analog circuit is arranged in parallel, by fixing the object to be detected on a processing table in the casing of the substrate processing apparatus, and the aforementioned high frequency alternating current One side of the output is connected to the housing, and the other side is connected to the middle of the input winding and the unwinding line of the current converter, so that the other end of the input winding is connected to the rotating shaft body, and the housing is connected via the bypass circuit to eliminate the winding. The other end is connected in parallel with one end of the reverse bypass circuit and one end of each analog circuit, and the other end of the reverse bypass circuit is connected to the housing, and the analog circuit corresponding to the electrostatic capacitance generated between the housing insulated from the rotating shaft body and the rotating shaft The other end of the connecting circuit, the other end of the analog circuit corresponding to the electrostatic capacitance generated between the rotating shaft body and the motor winding wire is connected to the winding of each phase of the motor of the rotating shaft, and the switch of the analog circuit is adjusted to make each corresponding electrostatic capacity In the same manner, the direction of the magnetic flux generated in the current transformer due to the current flowing through the input winding and the elimination winding is canceled, and the current generated by the contact between the tip end of the rotating shaft and the object to be detected can be detected from the detector. The change, as a change in the current output from the converter, constitutes a falling distance information detector that can recognize the falling distance information of the drill bit Structure.    The processing depth control mechanism according to claim 1, wherein the falling distance information detecting mechanism has a high frequency alternating current power source, two input winding wires having the same number of coils, and a high frequency current transformer having one or more output winding wires, and an analog substrate a circuit, the analog substrate circuit is a capacitor and a switch arranged in series, and the capacitor of the multiple array is arranged in parallel with the switch, and one side of the output of the high-frequency AC power source is connected to the housing and connected to the analog substrate circuit One side terminal and the other side are connected to the other end terminal of the analog substrate circuit via the two input winding wires of the current transformer, and the shell of the substrate processing device is adjusted by adjusting the switch of the analog substrate circuit The electrostatic capacitance generated between the detection object fixed to the processing table in the casing and the casing is slightly equal, so that the input winding current causes the magnetic flux generated by the converter to cancel each other, and can be detected from the detector. The change in current generated by the contact between the tip of the drill shaft and the object to be detected is a change in the current output from the converter. It is recognizable from the drop drop the drill information from the testing organization of information.    A substrate processing apparatus comprising the processing depth control mechanism as claimed in any one of claims 1 to 4.    A back-drilling processing method using any one of the substrate processing apparatuses according to claim 5, wherein: 1. the length of the substrate thickness, the reference residual length, and the design reserved error range (residual amount) in design And the numerical information of the predetermined thickness of the layer of the plating layer provided in the hole portion of the perforation and the angle of the tip angle of the drill bit; 2. placed on the processing table of the substrate processing apparatus, and at least the upper surface is formed as a lower layer of the conductor layer In the board, the measurement point determined by the following setting and the coordinate position information of each area on the plane are determined, and the measurement point is: the area in which the grid area is separated by a plurality of areas, in units of each area, and on the same basis One of the determined measurement points, or a sub-region in which each region is further divided into a lattice-like sub-region on the same basis, and each sub-region is determined by the same reference. 3. For each of the above-mentioned measurement points, the height position information of each measurement point measured by the lowering distance information detecting means is lowered by the rotation axis provided by the drill bit for back drilling processing. 4. The multilayer printed wiring board on the lower plate placed on the processing table of the substrate processing apparatus or the mother board present in front of the plurality of multilayer printed wiring boards (hereinafter referred to as "mother board" ") the coordinate position information of each back-drilling processing position on the plane; 5. by descenting the rotating shaft to the backing processing position of the substrate or the mother board, each of the measured by the falling distance information detecting mechanism The height position information of each of the back drilling processing positions; the position information and the like described in each of the above 1 to 5 are recorded on the recording medium, and the coordinate information of each of the respective regions and the presence of the multilayer printed wiring board or the mother thereof The individual coordinate position information of the back-drilling processing position on the board is extracted in the state where the lower board is placed with the multilayer printed wiring board or the mother board in the back drilling process, and exists in each coordinate range of each area of the lower board The back drilling processing position, and then automatically control the machining depth of the back drilling processing in the substrate processing apparatus according to the individual back drilling processing depth L2c calculated by the following formula: L2c=Lnd×(L2m -αave)/L2d-td+corner tan1; Lnd=designed reference excess length; L2m=multilayer printed wiring substrate or its mother board placed on the lower plate on the processing table, located in each region existing on the lower plate The measured height of each back-drilling machining position in the individual coordinate range; αave = the average of the measured heights of the measured points of the individual areas of the lower plate on the processing table; L2d = the thickness of the multilayer printed wiring substrate on the design; td = length of the design tolerance range; angle tan1 = predetermined thickness of the layer of the perforated plated portion x tan {(180 degrees - angle of the tip angle of the drill bit) ÷ 2}.    A back-drilling processing method using any one of the substrate processing apparatuses according to claim 5, wherein: 1. the length of the substrate thickness, the reference residual length, and the design reserved error range (residual amount) in design And numerical information on the radius of the hole portion of the perforated hole to be subjected to the back drilling process and the angle of the tip end angle of the drill bit in the plating portion; 2. placed on the processing table of the substrate processing apparatus, and at least the upper surface is configured as In the lower plate of the conductor layer, the measurement point determined by the following setting and the coordinate position information of each region on the plane are determined, and the measurement point is: a region in which a plurality of cells are separated by a grid-like region, in units of each region, and One measurement point determined on the same basis, or in each of its regions, the sub-regions further divided into lattices on the same basis for each region, and determined by the same sub-region and on the same basis One measurement point; 3. For each of the above-mentioned measurement points, the rotation axis set by the drill bit for back-drilling is lowered, and the respective measurement points measured by the falling distance information detecting means are individually high. Position information; 4. A multi-layer printed wiring board existing on the lower plate placed on a processing table of the substrate processing apparatus, or a mother board existing in front of a plurality of multi-layer printed wiring boards (hereinafter referred to as Information on the coordinate position of each back-drilling processing position on the plane on the "mother board"; 5. in the state where the substrate or the mother board is placed with the aluminum plate upper plate having the known thickness, by rotating the aforementioned rotating shaft To each of the back-drilling processing positions, the height position information of each of the back-drilling processing positions measured by the falling distance information detecting means is recorded, and the position information and the like described in each of the above 1 to 5 are recorded on the recording medium, and Information on the coordinate position of each of the above-mentioned regions and the coordinate position information of the back-drilling processing position existing on the multilayer printed wiring board or its mother board, and the multi-layer printed wiring board or its mother board is placed on the lower board during the back-drilling process. In the state of the back-drilling processing in the respective coordinate range of each region of the lower plate, and according to the individual back-drilling processing depth L2c automatically calculated by the following formula, The machining depth of the back drilling process in the dynamic control substrate processing device: L2c = Lnd × (L2m1 - αave - tAL) / L2d - td + tAL + angle tan2; Lnd = design basis excess length; L2m1 = placed on the processing table On the multilayer printed wiring board or the mother board on the lower panel, in a state in which an aluminum upper plate having a known thickness is further placed and fixed, each of the individual coordinate ranges existing in each region of the lower plate is extracted. The measured height of the back drilling processing position; αave = the average of the measured heights of the measurement points of the individual areas in the lower plate on the processing table; L2d = the thickness of the multilayer printed wiring substrate on the design; td = the design error margin The length of the plate; tAL = the specified thickness of the upper plate of the aluminum; the angle tan2 = the predetermined thickness of the perforation of the plated portion × tan {(180 degrees - the angle of the front end angle of the drill bit) ÷ 2}.    The back-drilling processing method according to claim 7, wherein, in the back-drilling process, the multilayer printed wiring board or the mother board on the lower plate placed on the processing table of the substrate processing apparatus is further loaded with a known thickness The aluminum upper plate is placed on an insulating upper plate that can be rotated by a shaft.