JP2008150639A - Electroplating method and electroplating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electroplating device which allows to remove a board having high possibility that the thickness of a plated film does not reach a prescribed thickness because a normal electric current has not flown is high, by detecting whether the electric current for plating has flown normally or not for every each board. <P>SOLUTION: When plating is applied onto print boards 3 by an electroplating device of a push bar system, the cathode current value flowing through a rack 1 of each board is measured when the board is plated, and at the same time, the rack discrimination number used for every each board and the plating jig discrimination number used for every each board are read, and the measured results and the read results are input in a computer 10. Further, after completion of plating, it is possible to confirm whether the integrated value of the cathode current of each rack 1 is within a preset range previously input as the preset values in the computer 10 or not. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electrolytic plating method and an electrolytic plating apparatus in the manufacture of printed wiring boards and the like.

  In recent years, printed circuit boards and other substrates on which electronic components and semiconductors are mounted have finer wiring pitches, and accordingly, the quality level is required to be improved. In particular, in the case of a substrate having an electrical connection with a semiconductor, it is required to make the copper wiring pitch fine. The copper wiring is generally formed by a subtractive method, that is, a method of etching copper.

  In a multilayer printed board having an interlayer connection by copper plating, the thickness of the outermost layer copper is affected by the variation in the copper plating thickness of the interlayer connection in the board. The copper plating thickness varies within the substrate and the thickness of the wiring formed by etching also varies. Therefore, in order to form a fine wiring pattern, it is necessary to reduce the in-plane variation of the copper plating thickness and the variation between the substrates. is important.

In order to reduce the variation in the substrate, a shielding plate that equalizes the plating thickness is used for each substrate. In order to reduce the variation in the plating thickness between the substrates, a method of making the plating current constant, that is, the current of each anode is made constant. By recording this current value and verifying the anode current when plating each substrate, it is possible to manage whether or not the plating has been performed normally. In the printed circuit board, a push bar type electroplating apparatus for continuously processing a large number of substrates is used in order to ensure mass productivity.
Japanese Patent No. 2941902

  However, in the case of a push-type plating apparatus in which a plurality of substrates and a plurality of anodes are installed in the same plating tank, a problem occurs even if each anode current is controlled. That is, when electrical contact between a set of “rack-plating jig-plated substrate” in the same plating tank is insufficient, even if the anode current is constant, the substrate with insufficient contact The cathode current to the is reduced. This is because the anode current flows to the other normal substrate side. As a result, the plating thickness of the substrate that has been insufficiently contacted due to a decrease in the cathode current does not become a predetermined thickness.

  The present invention has been made in view of such circumstances, and the purpose thereof is to measure the current value of the cathode current for each substrate and detect whether the plating current of each substrate has flowed normally. Another object of the present invention is to provide an electroplating apparatus and an electroplating method that can exclude a substrate in which a normal current does not flow.

  In order to achieve the above object, the electroplating method according to the present invention, when performing plating on a printed board by a push bar type electroplating apparatus, when each board is being plated, flows to the rack for each board. In addition to measuring the cathode current value, the rack identification number used for each substrate and the plating jig identification number used for each substrate are read, and these measurement results and the read results are input to the computer. It is to be recorded.

  In addition to the above-described invention, after the completion of plating, it is possible to confirm whether or not the integrated value of the cathode current of each rack is within a setting range that has been previously input as a setting value to the computer.

  Further, in addition to the above invention, the plating current value in each rack is measured by an ammeter attached to each rack, the current value is wirelessly transmitted by a transmitter attached to each rack, and the transmitted current value is received by a receiving device. And the data received by the receiving device is recorded in a computer as the plating current value of each substrate.

  Furthermore, in addition to the above invention, in the plating input section, the identification number assigned to each plating jig and the identification number assigned to each rack are read by an image reader, and the plating jig identification number used on each substrate and The rack identification number is input and recorded in a computer, and then the rack is moved to put the substrate into the plating tank.

  In order to achieve the above object, the electrolytic plating apparatus according to the present invention is a panel plating apparatus for a printed circuit board by a push bar method, and measures the cathode current flowing in the rack when each substrate is being plated. And a reading device that reads the used rack identification number and the used plating jig identification number, and inputs the cathode current measurement result and reading information by the reading device for each rack. Is provided with a computer for recording the integrated value of the cathode current.

  Further, in addition to the above invention, a normal integrated value of the cathode current can be set in the computer, and whether or not the integrated value of the cathode current is within the setting range is displayed for each rack.

  According to the present invention, it is possible to provide an electrolytic plating method and an electrolytic plating apparatus capable of detecting whether or not the plating current of each substrate normally flows and identifying and excluding the substrate where the normal current did not flow. Is possible. The electrolytic plating method of the present invention can also be carried out by adding an ammeter, a reading device, and a computer for processing these results to an existing plating facility.

  Embodiments of the present invention will be described with reference to the illustrated examples. The electrolytic plating apparatus of the present invention is a general push bar system as plating equipment, and includes a rack 1, a plating jig 2, a printed circuit board 3 to be plated, an anode 4, a cathode rail 5, and a plating power source 6. . In the present invention, the ammeter 7 installed in each rack 1, the receiver 8 for acquiring wireless data from the ammeter 7, the identification number of the plating jig 2 and / or the identification number of the rack 1 is read. A reading device 9 and a computer 10 that collects data from these devices and stores them as information for each substrate are added. In addition, 11 is a plating tank, and 12 is a plating apparatus loading part located on the near side of the plating tank 11.

  In addition, a barcode serving as a unique identification number for identifying each of the rack 1 and the plating jig 2 is pasted. If one of the identification number of the rack 1 and the identification number of the plating jig 2 is associated with the printed circuit board 3 to be plated, the printed circuit board 3 at that time can be identified. In order to perform easily, it is desirable that both the identification number of the rack 1 and the identification number of the plating jig 2 can be recorded in the computer 10 in association with the printed board 3 at that time.

  First, an embodiment of the electrolytic plating apparatus of the present invention will be described with reference to FIG. FIG. 1 is an explanatory view showing the configuration of the electrolytic plating apparatus of the present invention. The push bar type electroplating apparatus includes a plating tank 11, a rack 1, a plating jig 2, a printed circuit board 3 as a substrate to be plated, an anode 4, a cathode rail 5, and a plating power source 6. These basic parts are the same as those conventionally used.

  Each rack 1 is provided with an ammeter 7 for measuring the current value of the rack 1. The ammeter 7 includes, for example, a detection type DC current sensor using a Hall element and a transmitter that wirelessly transmits a DC voltage output from the sensor. In the present embodiment, a direct current sensor (model HCS-AP-CL manufactured by URD Corporation) using a Hall sensor that can be externally attached to a portion where a current of a normal rack flows is used. Other methods, for example, a method of inserting a low-resistance shunt resistor in series with the rack may be used. In this case, however, it is necessary to create a dedicated rack in order to attach a shunt resistor. Whichever current measurement method is employed, it suffices if the current value of the rack 1 can be measured. This is because the current value flowing through the corresponding printed circuit board 3 can be known by measuring the current value of the rack 1.

  In the present embodiment, an RVR 71 (manufactured by T & D Co., Ltd.) was used as the device that wirelessly transmits the current value measured by the ammeter 7 to the receiving device 9. Although transmission can be performed at any specified interval, for example, transmission is performed at intervals of 10 seconds. The current value data from each rack 1 is received by one common receiving device 8. The reading device 9 for acquiring the identification number of the plating jig 2 and the identification number of the rack 1 reads the barcode attached to each of them with a barcode reader installed in the plating apparatus loading unit 12. As another method that does not use a data code such as a bar code, the numbers written on the plating jig 2 and the rack 1, for example, 1, 2, 3,. There is also a method for recognizing numbers. The reading result may be transmitted from the reading device 9 to the receiving device 8 wirelessly or may be directly input to the computer 10.

  The current value data of the rack 1 received by the receiving device 8 together with the identification number of each rack 1 is sequentially input to the computer 10 and recorded. In addition, the computer 10 can set a predetermined value for the cathode current value, and determines whether or not the recorded current value for each rack is within the setting range, and displays or prints out the screen. Thus, the result is understood for each substrate.

Next, the electrolytic plating method of the present invention using the above-described electrolytic plating apparatus of the present invention will be described below.
First, a bar code serving as a unique identification number for identifying each rack 1 and each plating jig 2 is pasted. Next, a printed circuit board 3 to be plated is set on the plating jig 2. The printed board 3 does not require an identification number. This is because the printed board 3 can be identified by specifying the rack 1 and the plating jig 2 used for it. Then, the rack 1 is moved in the arrow direction along the cathode rail 5.

  In the plating apparatus loading unit 12, the identification number written on the plating jig 2 and the identification number written on each rack 1 are read by the image reading device 9. Then, the identification number of the plating jig 2 and the identification number of the rack 1 are wirelessly transmitted to the receiving device 8, and the reception result is input to the computer 10 and recorded. Thereby, the plating jig 2 moved by the rack 1 is specified, and as a result, the printed board 3 is also specified. The identification number reading result may be directly input from the reading device 9 to the computer.

  Next, the rack 1 is moved and the printed circuit board 3 is put into the plating tank 11 to perform the plating process. At this time, the cathode current value at that time and the identification number of the rack 1 are wirelessly transmitted to the receiving device 8 at regular time intervals for each rack 1 (for example, every 10 seconds). The receiving device 8 sequentially inputs this data to the computer 10. As a result, the computer 10 records the identification number of the rack 1 used, the identification number of the plating jig 2 used, and the cathode current value at each time during plating for each printed circuit board 3.

  The integrated value of the cathode current is calculated by the computer 10 for each printed circuit board 3. The integrated value is compared with a normal integrated value range preset in the computer 10 by the computer 10, and the result is displayed on the screen. Alternatively, it may be printed out and displayed in the form of a list. In any case, the integrated value of the cathode current of each printed circuit board 3 and the plating jig 2 used for the printed circuit board 3 need only be specified. As a result, the integrated value of the cathode current of each printed circuit board 3 is known, and the printed circuit board 3 whose integrated value of the cathode current is outside the set range is also known. And the board | substrate with a poor plating can be excluded by removing the printed circuit board 3 displayed out of the setting range after the end of plating.

  In order to confirm whether or not abnormality detection is possible when the printed circuit board is plated with copper by the electrolytic plating method of the present invention using the electrolytic plating apparatus of the present invention, the following experiment was conducted.

  As an experimental sample, an abnormal plating jig was prepared in which the contact resistance was increased by loosening the screw at the electrical connection portion of the plating jig. This abnormal plating jig was mixed with another normal plating jig, and all 30 printed boards were plated with the same anode plating current setting. After verifying the integrated value of the cathode current of each plating jig after the experiment, the identification number of the plating jig detected as being out of the current integrated value range set in advance as a preset range was prepared in advance as an experimental sample. It coincided with the identification number of the abnormal plating jig.

  On the other hand, when the value of the current flowing on the anode side counted for each substrate was confirmed, there was no abnormality in this value. That is, the plating current abnormality which was not found in the conventional anode current recording could be detected in the present invention.

  The electroplating apparatus and electroplating method of the present invention are not limited to electroplating apparatuses in the production of printed wiring boards and the like, but can be applied to various plating objects as long as they are push bar type electroplating, and the application range is extremely It will be wide.

It is explanatory drawing which shows the structure of the electroplating apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rack 2 Plating jig 3 Printed circuit board 4 Anode 5 Cathode rail 6 Plating power supply 7 Ammeter 8 Receiving device 9 Reading device 10 Computer 11 Plating tank 12 Plating device input part

Claims (6)

  When plating on printed circuit boards using a push bar type electroplating system, when each board is being plated, the cathode current value flowing to the rack is measured for each board and used for each board. An electroplating method characterized in that a rack identification number and a plating jig identification number used for each substrate are read, and the measurement results and the read results are input to a computer and recorded.   The electrolytic plating method according to claim 1, wherein after the completion of plating, it is possible to confirm whether or not the integrated value of the cathode current of each rack is within a set range that is previously input as a set value to the computer.   The plating current value in each rack is measured by an ammeter attached to each rack, this current value is wirelessly transmitted by a transmitter attached to each rack, and the received current value is received by a receiving device. The electrolytic plating method according to claim 1 or 2, wherein the data received in step (1) is recorded in a computer as a plating current value of each substrate.   In the plating input section, the identification number assigned to each plating jig and the identification number assigned to each rack are read by an image reader, and the plating jig identification number and rack identification number used for each substrate are input to the computer. The electrolytic plating method according to any one of claims 1 to 3, wherein the recording is performed and then the rack is moved so that the substrate is placed in a plating tank.   A panel plating apparatus for printed circuit boards by a push bar method, an ammeter that measures the cathode current flowing in the rack when each board is being plated, and the rack identification number used and the used Equipped with a computer that records the cathode current integrated value for each rack by inputting the cathode current measurement result and reading information by the reader. Electrolytic plating apparatus characterized by.   6. The electrolytic plating apparatus according to claim 5, wherein a normal integrated value of the cathode current can be set on a computer, and whether or not the integrated value of the cathode current is within a set range is displayed for each rack.

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