JP2009177180A - Resistor lamination conductor for print circuit board and its production method, and printed circuit board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resistor lamination conductor for a print circuit board and its production method, and the printed circuit board, in which the surface resistance of a resistance layer, a resistance deflection, and a resistance change rate, etc. are optimized. <P>SOLUTION: The resistor lamination conductor for the print circuit board includes a copper foil, and the resistance layer sit on one surface of the copper foil. The resistance layer has the surface resistance after annealing of 20-200 Ω/sq, the deflection in the surface resistance after annealing of ≤5%, and the resistance change rate after annealing of ≤3%. The resistance layer includes selected any one or more of sulfur (S), carbon (C), oxygen (O), and iron (Fe) as impurities, in ≤5,000 ppm based on atomic total amount criterion. The deflection in the impurities is <20%, and the deflection in the thickness is <5%. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a printed circuit board (PCB) conductor, and more particularly, to a printed circuit having a structure in which a thin-film resistance layer is provided on a copper foil in order to form an embedded resistance in the printed circuit board. The present invention relates to a resistance laminated conductor for a substrate, a manufacturing method thereof, and a printed circuit board.

  In recent years, printed circuit boards used in various portable electronic devices have a tendency to be embedded in circuit wiring and components in order to realize high-speed operation and high density of elements and downsizing of devices. ing.

  Embedded printed circuit boards are next-generation products that have the advantage that passive components such as resistors and capacitors and integrated circuits (ICs) are built into the board itself, reducing the occupied area and signal interference. It can be usefully applied to IT related products. In particular, when an embedded resistor is formed on a printed circuit board, other components can be arranged at a position where a conventional surface-mount resistor is mounted, so that the use efficiency of the substrate can be improved. .

  As a technique for forming an embedded resistor on a printed circuit board, a method of applying a carbon-based embedded paste of Asahi Chemical Industry has been widely used. As a technique related to this, Korean Patent Publication No. 2007-77823 (a printed circuit board having embedded resistors and a method for manufacturing the same) () is cited.

  However, when the embedded paste is used, there is a disadvantage that the resistance deviation and the resistance change rate are large, and the specification of the applicable printed circuit board product is limited. If the resistance deviation of the embedded resistor becomes too large, the resistance value will be too small or too large locally, and the desired product characteristics cannot be realized, and if the resistance change rate is large, product design will be difficult. is there.

  In recent years, a thin-film conductor with a small resistance deviation and resistance change rate is commercially available from Gould, Inc. of the United States, and embedded PCBs using this are mass-produced. However, in the case of this product, the surface resistance is indispensable for mobile devices due to the characteristic that it has a low resistance that is only about several tens of Ω / square (hereinafter referred to as “Ω / sq”). However, there is a disadvantage that it is impossible to form high and low antibodies. Thus, if the resistance value is too small, the resistance layer cannot sufficiently fulfill its role. On the other hand, if the resistance value of the embedded resistor is too large, the amount of heat generation is large and there is a risk of circuit damage. Therefore, the surface resistance must be designed within an appropriate resistance value.

Korean Patent Publication No. 2007-77823

  The present invention was devised in view of the above-mentioned problems, and the surface resistance, resistance deviation, resistance change rate, etc. of the resistance layer were optimized so that the embedded resistance value can be designed for general use. An object of the present invention is to provide a resistance laminated conductor for a printed circuit board, a manufacturing method thereof, and a printed circuit board.

  In order to achieve the above-described object, the present invention provides a resistance laminated conductor for a printed circuit board including a copper foil and a resistance layer provided on one surface of the copper foil. The surface resistance is 20 to 200Ω / sq, the deviation of the surface resistance after heat treatment is 5% or less, the rate of change in resistance before and after heat treatment is 3% or less, and sulfur (S), carbon (C), oxygen (O ) And any one or more selected from iron (Fe) in an amount of 5000 ppm or less based on the total atomic amount, the deviation of the impurities is less than 20%, and the thickness deviation is 5% or less. A resistive laminated conductor for printed circuit boards is disclosed.

  The resistance layer may be made of any one or more selected from nickel (Ni), chromium (Cr), aluminum (Al), and silicon (Si).

Alternatively, the resistive layer may be nickel (Ni) -chromium (Cr), nickel (Ni) -chromium (Cr) -aluminum (Al) -silicon (Si), or chromium (Cr) -silicon oxide (SiO ₂ ) alloy. It can consist of layers.

  The resistive laminated conductor for a printed circuit board may further include a silane layer.

  According to another aspect of the present invention, for a printed circuit board, comprising: preparing an electrolytic copper foil; and depositing a resistive layer on one surface of the electrolytic copper foil using vacuum sputtering. A method of manufacturing a resistive laminated conductor is provided.

  According to still another aspect of the present invention, in a printed circuit board comprising: a base substrate; and a resistance laminated conductor that is embedded in the base substrate and includes a copper foil and a resistance layer laminated on the copper foil. The resistance layer has a surface resistance after heat treatment of 20 to 200Ω / sq, a deviation of surface resistance after heat treatment of 5% or less, a rate of change in resistance before and after heat treatment of 3% or less, and sulfur (S), carbon as impurities One or more selected from (C), oxygen (O), and iron (Fe) are contained in an amount of 5000 ppm or less based on the total atomic amount, the deviation of the impurities is less than 20%, and the thickness deviation Is 5% or less, a printed circuit board is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the resistance laminated conductor for printed circuit boards excellent in the etching property of a resistance layer, resistance workability, and crack generation prevention property is provided. Therefore, it is possible to realize an embedded resistor that can be designed and applied to printed circuit board products having a wide range of specifications.

The following drawings attached to the specification illustrate preferred embodiments of the present invention, and together with the detailed description, serve to further understand the technical idea of the present invention. It should not be construed as being limited to the matters described in the drawings.
1 is a perspective view illustrating a configuration of a resistive laminated conductor for a printed circuit board according to a preferred embodiment of the present invention. 1 is a perspective view illustrating an application example of a resistive laminated conductor for a printed circuit board according to a preferred embodiment of the present invention.

  Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms and words used in this specification and claims should not be construed to be limited to ordinary or lexicographic meanings, and the inventor himself should explain the invention in the best possible manner. It must be interpreted with the meaning and concept corresponding to the technical idea of the present invention in accordance with the principle that the term concept can be appropriately defined.

  Therefore, the configuration described in the embodiments and drawings described in this specification is only the most preferable embodiment of the present invention, and does not represent all of the technical idea of the present invention. It should be understood that there are various equivalents and variations that can be substituted at the time of filing.

  FIG. 1 is a perspective view illustrating a configuration of a resistive laminated conductor for a printed circuit board according to a preferred embodiment of the present invention.

  Referring to FIG. 1, the resistive laminated conductor for a printed circuit board includes a copper foil 101 and a resistance layer 102 provided on one surface of the copper foil 101. Although not shown, a silane layer may be further provided on the copper foil 101 in order to improve the adhesive force with a predetermined film bonded to the copper foil 101.

  The copper foil 101 is provided in the form of an electrolytic copper foil manufactured in a general electrolytic copper foil manufacturing process, and the thickness is desirably 12 to 70 μm.

The resistance layer 102 is formed by depositing a resistance material on one surface of the copper foil 101. Here, as the resistance material, any one or more selected from nickel (Ni), chromium (Cr), aluminum (Al), and silicon (Si) may be adopted, and more preferably. Nickel (Ni) -chromium (Cr), nickel (Ni) -chromium (Cr) -aluminum (Al) -silicon (Si), or chromium (Cr) -silicon oxide (SiO ₂ ) alloy may be adopted. Considering the thickness of the copper foil 101, the thickness of the resistance layer 102 is desirably 100 to 2000 mm.

  The resistance layer 102 has physical properties such that the surface resistance after a predetermined heat treatment is 20 to 200 Ω / sq, the deviation of the surface resistance after the heat treatment is 5% or less, and the resistance change rate before and after the heat treatment is 3% or less. Here, the heat treatment condition can be determined by holding at a temperature of 85 ° C. and a relative humidity of 85 RH for 1000 hours.

The surface resistance of the resistance layer 102 is desirably determined by an average value obtained by measuring a surface resistance value of 40 points or more using a normal surface resistance measurement 4-point probe. The resistance deviation is calculated by the formula ((Max−Min) / (Max + Min)) × 100, where Max is the maximum value and Min is the minimum value among the data obtained by measuring the surface resistance value of 40 points or more. The resistance change rate is calculated by the formula ((R _S2 −R _S1 ) / R _S1 ) × 100, where R _S1 and R _S2 are the surface resistances before and after the heat treatment on the resistance layer 102, respectively.

  The resistance layer 102 includes one or more selected from among sulfur (S), carbon (C), oxygen (O), and iron (Fe) as impurities in an amount of 5000 ppm or less based on the total atomic amount. The impurity deviation at this time is less than 20%. Here, the content of impurities is determined by measuring 5 points using a normal ICP M / S instrument and then obtaining the average value. Further, the impurity deviation is calculated by the formula ((Max−Min) / (Max + Min)) × 100, where Max is the maximum value and Min is the minimum value of the measured data during the quantitative analysis using the ICP M / S instrument. Calculated.

  The thickness deviation of the resistance layer 102 is 5% or less. Here, the thickness deviation is calculated by measuring the thickness after polishing the cross section of the resistive laminated conductor.

  The resistance laminated conductor satisfying the numerical range as described above is excellent in the etching property, resistance workability, crack generation prevention property, etc. of the resistance layer 102, and the embedded resistance value can be freely designed to reduce the defect occurrence rate during processing. be able to.

  The resistive laminated conductor for printed circuit boards having the above-described configuration is obtained by using nickel (Ni) -chromium (Cr) on one surface of an electrolytic copper foil using vacuum sputtering including a nickel (Ni) -chromium (Cr) target. ) Manufactured by vapor deposition of material.

  In the deposition process, if the target type and degree of vacuum, the voltage and current conditions applied to the sputtering are controlled, the deposition ratio of the resistance layer material, surface resistance, resistance deviation, resistance change rate, thickness deviation, impurity content, Impurity deviation can be adjusted.

  The resistance layer material may be one or more selected from nickel (Ni), chromium (Cr), aluminum (Al), and silicon (Si), or nickel (Ni). -Chromium (Cr), nickel (Ni) -chromium (Cr) -aluminum (Al) -silicon (Si), or chromium (Cr) -silicon oxide (SiO2) alloys may be employed.

  After the resistance layer is formed on the electrolytic copper foil, a step of forming a silane layer on the other surface of the resistance layer or the electrolytic copper foil may be further performed.

  The resistance laminated conductor manufactured by the present invention is processed in the form as shown in FIG. 2 and applied to a printed circuit board. That is, the resistive laminated conductor provides the embedded resistance and circuit wiring of the printed circuit board by having the resistance layer 102 attached on the base substrate 100 and embedded in a subsequent process. Of course, the form of the resistive laminated conductor is not limited to that shown in the drawings, and can be designed in various patterns.

  Table 1 is a table showing the results of measuring the resistance layer characteristics of the resistive laminated conductor for printed circuit boards according to the examples and comparative examples of the present invention. Table 1 shows the results of measuring the resistance layer characteristics of the resistive laminated conductor for printed circuit boards with respect to Examples and Comparative Examples of the present invention. In Table 1, the determination of the etching property is that the nickel (Ni) -chromium (Cr) resistance layer is not smoothly etched after the etching process which is essential when the printed circuit board is manufactured, and the etching is performed on the prepreg substrate. This was done with or without residue. The resistance processability is judged by whether or not a laser processing process can be applied to precisely adjust the resistance value. The resistance layer cracking prevention characteristic is nickel (exposed to high temperature and high pressure during the manufacturing process of the printed circuit board). The judgment was made based on whether or not cracks generated on the surface of the Ni) -chromium (Cr) thin film resistance layer could be suppressed.

  Referring to Table 1, the resistance laminated conductor for a printed circuit board according to the first to thirteenth embodiments of the present invention satisfies all the requirements of the resistance layer described above, thereby preventing etching, resistance workability, and crack generation. It can be confirmed that the property provides good characteristics.

  On the other hand, in Table 1, since the resistance laminated conductors for printed circuit boards according to Comparative Examples 1 to 16 do not satisfy at least one of the requirements for the resistance layer described above, etching resistance, resistance workability, or crack The results show that the prevention of occurrence is not good.

  Hereinafter, although a comparative example will be described, in the case of Comparative Examples 4, 5, 10 and 12 where the surface resistance of the resistance layer after the heat treatment is completed is out of the upper limit or lower limit of 20 to 200 Ω / sq, resistance workability or generation of cracks It can be confirmed that the prevention property is lowered.

  In the case of Comparative Examples 1, 7, and 13 in which the resistance deviation after the heat treatment of the resistance layer exceeds 5%, it can be confirmed that the etching property is lowered.

  In the case of Comparative Examples 2 and 9 in which the thickness deviation after the heat treatment of the resistance layer exceeds 5%, it can be confirmed that the etching property or cracking prevention property is lowered.

  In the case of Comparative Examples 6, 11, and 15 in which the resistance change rate before and after the heat treatment of the resistance layer exceeds 3%, it can be confirmed that the resistance workability or the crack generation prevention property decreases.

  Further, in the case of Comparative Example 14 in which the impurity content exceeds 5000 ppm, the etching property is poor, and in the case of Comparative Examples 3, 8 and 16 in which the impurity deviation is 20% or more, resistance workability or prevention of cracking is caused. It can be confirmed that the property is lowered.

The resistive laminated conductor for a printed circuit board according to the present invention has an etching property and resistance even if only one of conditions such as surface resistance, resistance deviation, thickness deviation, resistance change rate, impurity content, impurity deviation is satisfied. Workability, resistance layer cracking prevention properties, and the like can be improved. However, as shown in Comparative Example 1 to Comparative Example 16, when there is even one factor that deviates from the numerical range presented in the present invention, the resistance layer characteristics are eventually lowered. It is most desirable to satisfy all conditions.
As described above, the present invention has been described with reference to the limited embodiments and drawings. However, the present invention is not limited thereto, and the present invention can be obtained by those having ordinary knowledge in the technical field to which the present invention belongs. It goes without saying that various modifications and variations can be made within the scope of the technical idea and the scope of claims.

100 Base substrate 101 Copper foil 102 Resistance layer

Claims (19)

In a resistance laminated conductor for a printed circuit board comprising a copper foil and a resistance layer provided on one surface of the copper foil,
The resistance layer is
The surface resistance after heat treatment is 20 to 200 Ω / sq, the deviation of the surface resistance after heat treatment is 5% or less, the rate of change in resistance before and after heat treatment is 3% or less,
Any one or two or more selected from sulfur (S), carbon (C), oxygen (O), and iron (Fe) are included as impurities in an amount of 5000 ppm or less based on the total amount of atoms, and the deviation of the impurities is Less than 20%,
A resistance laminated conductor for a printed circuit board, wherein the thickness deviation is 5% or less.   The said resistance layer consists of any one selected from nickel (Ni), chromium (Cr), aluminum (Al), and silicon (Si), or two or more. Resistance printed circuit board for printed circuit boards. The resistance layer is a nickel (Ni) -chromium (Cr), nickel (Ni) -chromium (Cr) -aluminum (Al) -silicon (Si), or chromium (Cr) -silicon oxide (SiO ₂ ) alloy layer. The resistive laminated conductor for printed circuit boards according to claim 1, wherein the resistive laminated conductor is provided.   The resistance laminated conductor for a printed circuit board according to claim 1, further comprising a silane layer provided on the resistance layer or the copper foil. In a resistance laminated conductor for a printed circuit board comprising a copper foil and a resistance layer provided on one surface of the copper foil,
For the printed circuit board, wherein the resistance layer has a surface resistance after heat treatment of 20 to 200 Ω / sq, a deviation of surface resistance after heat treatment of 5% or less, and a rate of change in resistance before and after heat treatment is 3% or less. Resistive laminated conductor. In a resistance laminated conductor for a printed circuit board comprising a copper foil and a resistance layer provided on one surface of the copper foil,
The resistance layer includes 5000 ppm or less of any one or more selected from sulfur (S), carbon (C), oxygen (O), and iron (Fe) as impurities. A resistive multilayer conductor for a printed circuit board.   The resistance laminated conductor for a printed circuit board according to claim 6, wherein a deviation of the impurities is less than 20%.   6. The resistance layer according to claim 5, wherein the resistance layer is made of any one or more selected from nickel (Ni), chromium (Cr), aluminum (Al), and silicon (Si). Item 7. The resistive laminated conductor for printed circuit boards according to Item 6. The resistance layer is a nickel (Ni) -chromium (Cr), nickel (Ni) -chromium (Cr) -aluminum (Al) -silicon (Si), or chromium (Cr) -silicon oxide (SiO ₂ ) alloy layer. The resistive laminated conductor for printed circuit boards according to claim 5, wherein the resistive laminated conductor is provided.   The resistance laminated conductor for a printed circuit board according to claim 5 or 6, wherein a thickness deviation of the resistance layer is 5% or less.   The resistance laminated conductor for a printed circuit board according to claim 5, further comprising a silane layer provided on the resistance layer or the copper foil. In the method for manufacturing a resistance laminated conductor for a printed circuit board,
Preparing an electrolytic copper foil;
Depositing a resistance material on one surface of the electrolytic copper foil using vacuum sputtering and providing a resistance layer. A method for producing a resistance laminated conductor for a printed circuit board, comprising:   The method according to claim 12, further comprising a step of providing a silane layer on the other surface of the resistance layer or the electrolytic copper foil.   The resistance layer is made of any one or more selected from nickel (Ni), chromium (Cr), aluminum, (Al), and silicon (Si). Method for producing a resistive laminated conductor for printed circuit boards. The resistance layer is made of nickel (Ni) -chromium (Cr), nickel (Ni) -chromium (Cr) -aluminum (Al) -silicon (Si), or chromium (Cr) -silicon oxide (SiO ₂ ) alloy. The method for producing a resistance laminated conductor for a printed circuit board according to claim 12. In a printed circuit board comprising: a base substrate; and a resistive laminated conductor that is embedded in the base substrate and includes a copper foil and a resistive layer laminated on the copper foil.
The resistance layer is
The surface resistance after heat treatment is 20 to 200 Ω / sq, the deviation of the surface resistance after heat treatment is 5% or less, the rate of change in resistance before and after heat treatment is 3% or less,
Any one or two or more selected from sulfur (S), carbon (C), oxygen (O), and iron (Fe) are included as impurities in an amount of 5000 ppm or less based on the total amount of atoms, and the deviation of the impurities is Less than 20%,
A printed circuit board having a thickness deviation of 5% or less.   The resistance layer is made of any one or more selected from nickel (Ni), chromium (Cr), aluminum (Al), and silicon (Si). Printed circuit board. The resistance layer is a nickel (Ni) -chromium (Cr), nickel (Ni) -chromium (Cr) -aluminum (Al) -silicon (Si), or chromium (Cr) -silicon oxide (SiO ₂ ) alloy layer. The printed circuit board according to claim 16, wherein the printed circuit board is provided. The printed circuit board according to claim 16, further comprising a silane layer on the resistive laminated conductor.

Images