JP4830287B2 - Multilayer wiring board with end points for measurement and method for manufacturing the same - Google Patents

Description

  The present invention relates to a laminated wiring board with end points for measurement having a test pattern for impedance measurement and a method for manufacturing the same.

  A transmission line formed on a multilayer wiring board used in an electronic device or the like is required to match impedance in accordance with a signal to be transmitted. In particular, impedance matching is extremely important when the transmission signal is high speed (high frequency), and therefore, the impedance is designed from the time of designing the transmission line. A product whose impedance value is within a certain range from the design value is determined as a non-defective product (conforming product), and a product outside the range is selected as a defective product (non-conforming product).

  The impedance of the transmission line determines the quality of the product, and a warranty inspection is naturally performed when the product is shipped. There are two ways to test the impedance of a multilayer wiring board: when measuring and testing an actual transmission line, and by forming a test pattern for impedance measurement on the same layer as the transmission line in the excess part of the board, The latter is generally adopted. By measuring the impedance of the test pattern, it is possible to determine the quality of the product based on whether or not the measured value is within a certain range. Guarantee the degree of.

  In addition, the laminated wiring board forms a wiring layer by patterning a metal made of copper foil on both sides or one side of the core layer by a subtractive method or a semi-additive method, and laminates an insulating material such as polyimide or glass epoxy resin. Then, an insulating layer is formed, and this process is repeated a plurality of times. The conduction method between the layers varies depending on the construction method and material, but for example, a hole is formed in the insulating layer with a laser or the like, and a via is formed by plating, or a through hole is drilled with a drill or the like after all the layers are formed. Depending on vias formed by plating.

  As a method for performing the impedance inspection of the above-mentioned multilayer wiring board, the test pattern is formed not only on the outer layer but also on the inner layer including the core layer. It must be pulled out via vias on the outermost layer of the substrate. Therefore, in order to inspect the impedance of the multilayer wiring board, it is necessary to finish all the lamination processes up to the outermost layer. Therefore, inspection is impossible only after all steps are completed, so even if a transmission line that is defective due to impedance abnormality is formed in a specific inner layer, it cannot be found until the outermost layer inspection, and the final In particular, there is a problem that the substrate becomes defective, leading to product loss, high product cost, and time loss.

  In order to avoid this problem, there has been proposed a method of measuring the impedance of a test pattern by forming a measurement terminal of a test pattern for impedance measurement on an end surface of a multilayer wiring board and bringing the probe into contact with the end surface (for example, a patent) Reference 1).

In addition, there are multiple transmission lines to be measured and guaranteed in the multilayer wiring board in a plurality of layers and directions, and it is necessary to form a plurality of test coupons according to the type, and the probe is brought into end-contact with the end face of the multilayer wiring board. Thus, the method of measuring the impedance of the test pattern has a problem that a plurality of measurement terminals are scattered around the substrate, and it takes time to align the probe and causes a reduction in tact.
In addition, since there are measurement terminals at various positions in the alignment operation, the probe height control, and the push-in amount control, there is a problem that the measurement mechanism becomes complicated.
JP 2002-16335 A

  The present invention has been devised in view of the above problems, and an object of the present invention is to provide a multilayer wiring board with a measuring end point and a method for manufacturing the same, in which the characteristic impedance of the multilayer wiring board can be easily measured during the production of the multilayer wiring board. And

In order to achieve the above object in the present invention, first, in claim 1, a plurality of wiring layers, an impedance measurement test pattern, and a ground layer are formed on one or both sides of the core layer via an insulating layer. The test patterns facing in the stacking direction are conductive, the ground layers facing in the stacking direction are conductive, and the impedance measurement test pattern and the ground layer are not conductive. In addition, a measurement end point for impedance measurement is provided at an end of one surface of the core layer, and no lamination is performed in a region where the measurement end point of the core layer is provided. The end point protrudes from the wiring layer area ,
By laminating each insulating layer and each wiring layer of the multilayer wiring board in a predetermined order, the impedance measurement test pattern of each wiring layer becomes a stripline structure in order, and impedance measurement from the measurement end point Thus, a laminated wiring board with end points for measurement is provided.

  According to a second aspect of the present invention, the measurement end point includes a signal terminal and a ground terminal, the signal terminal is electrically connected to the impedance measurement test pattern, and the ground terminal is electrically connected to the ground layer. The laminated wiring board with end points for measurement according to claim 1, wherein:

  Further, according to claim 3, in the multilayer wiring board having a single area layer with respect to the core layer, the measurement end points are provided at two positions of the end portion of the core layer. 2. A laminated wiring board with end points for measurement described in 2.

  According to a fourth aspect of the present invention, in the laminated wiring board laminated on both sides with respect to the core layer, the measurement end points are provided at four positions of the end portion of the core layer, two of which are provided on the core layer. 3. The method according to claim 1, wherein the second wiring is for impedance measurement of the multilayer wiring on one surface, and the remaining two locations are for impedance measurement of the multilayer wiring on the other surface with respect to the core layer. This is a laminated wiring board with end points for measurement.

  Furthermore, in claim 5, there is provided the method for manufacturing a multilayer wiring board according to any one of claims 1 to 4, wherein the measurement pattern is measured when the impedance measurement test pattern has a stripline structure. Manufacturing a multilayer wiring board with measuring endpoints, measuring the impedance by bringing a probe into contact with the end point and confirming that the impedance value is within an allowable range. It is a method.

In the laminated wiring board with measurement endpoints of the present invention, the measurement endpoint for impedance measurement is formed at the end of the core layer and protrudes from the wiring layer region. Since the confirmation work can be performed, a laminated wiring board having excellent impedance characteristics can be manufactured.
In addition, by arranging the measurement end points of the laminated wiring board with measurement end points according to the present invention, the impedance of all layers except the outermost layer can be measured with a stripline structure regardless of the number of layers.

Embodiments of the present invention will be described below.
FIG. 1 is a schematic top view of a laminated wiring board 100 with measurement end points showing an embodiment of the laminated wiring board with end points for measurement of the present invention. FIG. 3 is a schematic top view of a laminated wiring board 200 with measurement end points showing another embodiment of the laminated wiring board with end points for measurement of the present invention.
2A is a schematic cross-sectional view of the laminated wiring board 100 with end points for measurement in FIG. 1 cut along the line AA ′, and FIG. 2B is a laminated wiring board with end points for measurement in FIG. FIG. 2C is a schematic cross-sectional view taken along the line BB ′, and FIG. 2C is a schematic cross-sectional view taken along the line CC ′ in FIG. .
The laminated wiring board 100 with end points for measurement has a signal terminal 15 and a ground terminal 16 at the end of the core layer 11 of a 6-layer laminated wiring board manufactured by sequentially laminating an insulating layer and a wiring layer on one side of the core layer 11. Are provided at two measurement end points (measurement end point 10a and measurement end point 10b).
The multilayer wiring board is provided with a test coupon including an impedance measurement test pattern and a ground layer in the same layer as the wiring layer region, and the impedance measurement measurement end point 10a and the measurement end point 10b formed in the core layer 11 are electrically connected. The core layer 11 in which the measurement end point 10a and the measurement end point 10b are formed protrudes from the wiring layer region.

  The signal terminals 15 of the measurement endpoint 10a and the measurement endpoint 10b are connected to the impedance measurement test pattern, and the ground terminal 16 is connected to the ground layer.

  As described above, the measurement-attached laminated wiring board 100 according to the present invention is formed on the core layer 11 in which the measurement end points 10a and the measurement end points 10b protrude from the laminated wiring board. Even during the process, impedance measurement can be performed by easily bringing a measurement probe used conventionally into contact with the measurement end point 10a and the measurement end point 10b.

Hereinafter, the principle of impedance measurement of the laminated wiring board 100 with end points for measurement will be described.
The impedance is measured by a TDR (Time Domain Reflectometry) method.
As shown in FIG. 11, this impedance measurement is made up of a (step) pulse generator and an oscilloscope, and (step) the ratio of the pulse voltage incident on the measurement object from the pulse generator and the reflected pulse voltage reflected from the measurement object. The reflection coefficient ρ is obtained from the above, and the impedance of the transmission line is obtained by an arithmetic expression and measured.

  In order to inject a voltage from a TDR measurement device to a measurement object, a measurement probe having a needle-shaped signal pin and a ground pin is generally used. Coaxial cables with good high-frequency transmission characteristics are used for connection between the measurement probe and the TDR measuring device, and those connection terminals with good high-frequency transmission characteristics are also used. The number of pins at the tip of the measurement probe is usually two to three for single-ended measurement, and is connected to the signal pin to be connected (contacted) to the signal line of the transmission line (measurement target) and the ground pattern of the transmission line (measurement target) It consists of a ground pin to make contact.

In the laminated wiring board 100 with measurement end points, measurement end points 10a and measurement end points 10b each including a signal terminal 15 and a ground terminal 16 are formed at the end of the core layer 11, and the centers of the measurement end points 10a and 10b are measured. A signal terminal 15 electrically connected to the impedance measurement test pattern is formed on both sides of the signal terminal 15, and a ground terminal 16 electrically connected to the ground layer is formed on both sides of the signal terminal 15.
This is because the pin at the tip of the measurement probe corresponds to one signal pin and two ground pins, so that one signal pin is in contact with the signal terminal 15 and two ground pins are in contact with the ground terminal 16. It has become.
The distance between the signal terminal 15 and the ground terminal 16 is appropriately set depending on the type of probe used.

  The signal terminal 15 and the ground terminal 16 of the measurement endpoint 10a and the measurement endpoint 10b are formed on one side of the core layer 11, but depending on the pin arrangement of the measurement probe tip, as shown in FIG. A signal terminal 15 for a signal pin is formed on one side and a ground terminal 16 for a ground pin is formed on the other side, and the core layer 11 is sandwiched between the signal pin and the ground pin at the tip of the measurement probe as shown in FIG. It is also possible to contact the signal terminal 15 and the ground terminal 16 of the measurement end point 10a and the measurement end point 10b.

Hereinafter, the manufacturing method of the laminated wiring board with end points for measurement of the present invention will be described.
The laminated wiring board differs depending on the lamination method and the layer on which impedance measurement is performed. For example, when impedance measurement is performed on one layer and all layers (excluding the back surface of the core), assuming that the layers are laminated from the 2nd layer to the 6th layer, as shown in FIGS. 2 (b) and 2 (c) Layer structure. When impedance measurement is performed on all layers, the test pattern of the present invention basically has a stripline structure, so it is impossible to measure all layers at one measurement end point. A line structure is necessary, and in this case, measurement end points 10 a and measurement end points 10 b are provided at two locations on the end of the core layer 11.

Hereinafter, the manufacturing method of the laminated wiring board with a measuring end point according to the present invention will be described with reference to FIGS.
First, the measurement end point 10a and the measurement end point 10b including the signal terminal 15 and the ground terminal 16 are provided at the end of the core layer 11, and the impedance measurement test pattern 12, the lead 15a, and the ground land are provided on one surface of the core layer 11. 17, the ground layer 18 and the wiring layer region 19 are formed on the other surface, and the ground layer 13, the via 14 and the wiring layer region (not shown in particular) are formed on the other surface, respectively. a) to (d)).
Here, the impedance measurement test pattern 12 is electrically connected to the signal terminal 15 via the signal land 12a and the lead 15a, and the ground layer 13 is electrically connected to the ground terminal 16 via the via 14.
Further, the signal terminal 15 and the ground terminal 16 at the measurement end point 10a and the measurement end point 10b can be appropriately arranged according to the pin arrangement of the probe used. For example, as shown in this example, a signal pin signal terminal 15 and a ground pin ground terminal 16 are arranged on one surface of the core layer 11, or a signal pin signal signal is disposed on one surface of the core layer 11. The signal terminal 15 may be any one in which the ground terminal 16 for the ground pin is arranged on the other surface.
Further, the measurement end point 10b is basically connected to the measurement end point 10a only by shifting the layer for forming the impedance measurement test pattern by one layer, and therefore, detailed description thereof is omitted here. Detailed description of the wiring layer region is also omitted.

Next, an insulating layer 21, a ground layer 22, a signal land 22a, a via 23, a via 24, an impedance measurement test pattern 27, a ground land 28, and a wiring layer region 29 are formed by a build-up process to form a three-layer wiring. The substrate 30 is produced (see FIGS. 6A to 6D).
Here, the ground layer 22 is electrically connected to the ground terminal 16 via the via 24, and the signal land 22 a is electrically connected to the signal terminal 15 via the via 23.

  Since the stripline structure is formed for the first time on the three-layer wiring board 30, it is possible to measure the impedance of the impedance measurement test pattern 12 formed on the core layer 11, and the end of the core layer 11 is measured using a TDR measuring instrument. When the probe is brought into contact with the measurement end point 10a formed in the section, an impedance waveform as shown in FIG. 13A is obtained, and the impedance can be measured.

Next, in the build-up process, the insulating layer 31, the impedance measurement test pattern 32, the via 33, the ground land 34, the via 35, the ground layer 38, and the signal land 38a.
And the wiring layer area | region 39 is formed and the 4 layer wiring board 40 is produced (refer Fig.7 (a)-(d)).
Here, the impedance measurement test pattern 32 is electrically connected to the signal terminal 15 via the via 33, and the ground land 34 is electrically connected to the ground terminal 16 via the via 35.
In this four-layer wiring board 40, the stripline structure of the impedance measurement test pattern 27 formed in the insulating layer 21 is formed, so that the probe is brought into contact with the measurement end point 10b using a TDR measuring instrument. The impedance of the impedance measurement test pattern 27 can be measured.

Next, an insulating layer 41, a ground layer 42, a signal land 42a, a via 43, a via 44, an impedance measurement test pattern 47, a ground land 48, and a wiring layer region 49 are formed by a build-up process to form a five-layer wiring. The substrate 50 is manufactured (see FIGS. 8A to 8D).
Here, the ground layer 42 is electrically connected to the terminal 16 via the via 44, and the signal land 42 a is electrically connected to the signal terminal 15 via the via 43.
In this five-layer wiring board 50, when an impedance measurement is performed with a probe brought into contact with the measurement end point 10a using a TDR measuring instrument, an impedance measurement test pattern 12 and an impedance measurement test pattern 32 are provided. The impedance of the book pattern is measured in parallel, and an impedance waveform as shown in FIG. 13B is obtained as a measurement result.

The two parallel impedance measurement test patterns are regarded as resistance elements of the electric circuit, and the resistance values of the impedance measurement test pattern 12 and the impedance measurement test pattern 32 are set to Z ₁ and Z ₂ , respectively. _Let Z _all be an impedance value obtained from the result of measuring two test patterns in parallel. Then, since the impedance of the impedance measurement test pattern 12 has been measured, Z ₁ becomes known. That is, from the calculation formula when the resistance elements are connected in parallel, 1 / Z _all = 1 / Z ₁ + 1 / Z ₂ , so that the resistance value (impedance value) Z ₂ of the impedance measurement test pattern 32 is
Z ₂ = (Z ₁ × Z _all ) / (Z ₁ −Z _all ).

Next, the insulating layer 51, the impedance measurement test pattern 52, the signal land 52a, the via 53, the ground land 54, the via 55, the ground layer 58, the signal land 58a, and the wiring layer region 59 are formed by a build-up process. Then, a six-layer laminated wiring board 60 is produced (see FIGS. 9A to 9D).
Here, the impedance measurement test pattern 52 is electrically connected to the signal terminal 15 via the via 53, and the ground land 54 is electrically connected to the ground terminal 16 via the via 55.
However, the impedance measurement test pattern 52 appears on the surface at the measurement end point 10a, and a stripline structure cannot be formed.

Finally, the solder resist 61 is formed to obtain the laminated wiring board 100 with measurement end points of the present invention (see FIGS. 10A to 10D).
Then, an impedance measurement is performed. Furthermore, the impedance of the impedance measurement test pattern 52 can be obtained from the above equation.

  As described above, in the multilayer wiring board having a single area layer, by providing two measurement end points including the measurement end point 10a and the measurement end point 10b on the core layer 11, it is possible to measure the impedance of all layers of the multilayer wiring substrate. Become.

Hereinafter, an example in which impedance measurement is performed in a process of manufacturing a multilayer wiring board by double-sided lamination will be described.
FIG. 3 is a schematic top view of a laminated wiring board 200 with measurement end points showing another embodiment of the laminated wiring board with end points for measurement of the present invention.
4A is a schematic cross-sectional view of the laminated wiring board 200 with end points for measurement in FIG. 3 cut along the line AA ′, and FIG. 4B is a laminated wiring board with end points for measurement in FIG. 200 is a schematic cross-sectional view taken along line BB ′, and FIG. 4C is a schematic cross-sectional view taken along line CC ′ in FIG. Show.
The laminated wiring board 200 with measurement end points is provided with an eight-layer measurement end point formed by forming a test pattern for impedance measurement, a ground layer, and a wiring layer region on both surfaces of the core layer 11 having end points for measurement. It is a laminated wiring board.
The basic layer configuration of the impedance measurement test pattern and the ground layer is the same as that of the single-layer laminated wiring board, but the number of measurement end points is greatly changed. In the single-layer multilayer wiring board, the impedance measurement of almost all layers was possible at two measurement end points, but in the double-layer laminated wiring board, the impedance measurement of all layers was performed at four locations. Are provided with measurement end points.

  When the measurement end points 10a, 10b, 10c, and 10d are provided on the eight-layer measurement-end-point laminated wiring board 200 shown in FIG. 3, for example, the measurement end points 10a and 10b are connected to the four-layer multilayer wiring board on one side. As the measurement end points, the measurement end points 10c, 10d are the measurement end points of the other one-sided four-layer laminated wiring board, so that four measurement end points 10a, 10b, 10c, By sequentially measuring the impedance of the impedance measurement test pattern provided on each layer using 10d, it is possible to measure the impedance of all the layers of the eight-layer laminated wiring board.

  Hereinafter, a method for manufacturing a laminated wiring board with end points for measurement of double-sided lamination will be described. Since the lamination process of the double-sided laminated wiring board is basically the same as that of the single area layer, the manufacturing process diagram is omitted.

First, the measurement end point 10a, the measurement end point 10b, the measurement end point 10c, and the measurement end point 10d including the signal terminal 15 and the ground terminal 16 are disposed at the end of the core layer 11, and the impedance measurement is performed on one surface of the core layer 11. A test pattern 12 and a signal land 12a are formed, and a ground layer 13 is formed on the other surface (see FIGS. 4B to 4C).
Here, the impedance measurement test pattern 12 is connected to the signal terminal 15 of the measurement end point 10a via the signal land 12a and the lead, and the ground layer 13 is connected to the ground terminal 16 via the lead (not shown). Electrically connected.

Next, the insulating layers 21a and 21b are formed by a build-up process, the ground layer 22, the signal land 22a, and the via 23 are formed on the insulating layer 21a, and the impedance measurement test pattern 24 and the signal land are formed on the insulating layer 21b. 24a, ground lands 25 and vias 26 are formed to produce a four-layer wiring board.
Here, the ground layer 22 is connected to the ground terminal 16 via the via 24, and the impedance measurement test pattern 24 is connected to the signal terminal 15 of the measurement end point 10c via the signal land 24a and leads (not shown). Each is electrically connected.
Here, since the stripline structure is formed in the impedance measurement test pattern 12 of the four-layer wiring board, the impedance of the impedance measurement test pattern 12 is brought into contact with the measurement end point 10a using a TDR measuring instrument. Can be measured.

Next, the insulating layers 31a and 31b are formed by a build-up process, and the impedance measurement test pattern 32, the signal land 32a, and the via 35 are formed on the insulating layer 31a.
A ground layer 36 and a via 37 are formed on 1b to fabricate a six-layer wiring board.
Here, the impedance measurement test pattern 32 is electrically connected to the signal terminal 15 of the measurement end point 10 a via the via 33, and the ground layer 36 is electrically connected to the ground terminal 16 via the via 37.
Here, since the stripline structure is formed in the impedance measurement test pattern 24 of the six-layer wiring board, the impedance of the impedance measurement test pattern 24 is brought into contact with the measurement end point 10c using a TDR measuring instrument. Can be measured.

Next, insulating layers 41a and 41b are formed on both surfaces by a build-up process, a ground layer 42, signal lands 42a and vias 43 are formed on the insulating layer 41a, an impedance measurement test pattern 44 and signals are formed on the insulating layer 41b. Lands 44a, ground lands 45, and vias 46 are formed, and a laminated wiring board having two layers on both sides is fabricated.
Here, the ground layer 42 is electrically connected to the ground terminal 16 via the via 44, and the impedance measurement test pattern 44 is electrically connected to the signal terminal 15 of the measurement end point 10c via the signal land 44a and the via 46, respectively. The
Here, the parallel impedance of the impedance measurement test pattern 12 and the impedance measurement test pattern 32 is measured at the measurement end point 10a of the 8-layer wiring board, and the impedance of the impedance measurement test pattern 12 is known. Therefore, the impedance of the impedance measurement test pattern 32 can be obtained from the above equation.
However, at the measurement end point 10c, the impedance measurement test pattern 44 appears on the surface, and a stripline structure cannot be formed.

Finally, the solder resist 62 is formed to obtain the laminated wiring board 200 with measurement end points of the present invention (see FIGS. 3 and 4A to 4C).
And the impedance of all the layers of an 8-layer wiring board can be measured by measuring an impedance.
Although the measurement end point 10b and the measurement end point 10d are not described in detail, impedance measurement similar to that of the measurement end point 10a and the measurement end point 10c can be performed.
In this way, in the case of a double-sided laminated wiring board, the impedance of the strip line is measured at the measurement end point 10a, the measurement end point 10b, the measurement end point 10c, and the measurement end point 10d. It becomes possible to measure beading.

Hereinafter, specific examples of the laminated wiring board with measurement end points will be described.
First, an insulating layer in which copper foils are laminated on both surfaces is used as a core layer 11, and measurement end points 10 a and measurement end points 10 b including a signal terminal 15 and a ground terminal 16 are provided on one end of the core layer 11. A test pattern 12 for impedance measurement, a lead 15a, a ground land 17, a ground layer 18 and a wiring layer region 19 are formed on one surface of the layer 11, and a ground layer 13 and a via 14 are formed on the other surface. A plate 20 was produced (see FIGS. 5A to 5D).
The design value of the impedance value of the impedance measurement test pattern formed here is 75Ω.

Next, an insulating layer 21, a ground layer 22, a signal land 22a, a via 23, a via 24, an impedance measurement test pattern 27, a ground land 28, and a wiring layer region 29 are formed by a build-up process to form a three-layer wiring. A substrate 30 was produced (see FIGS. 6A to 6D).
Here, the ground layer 22 was electrically connected to the ground terminal 16 via the via 24, and the signal land 22 a was electrically connected to the signal terminal 15 via the via 23.
Furthermore, it becomes possible to measure the impedance of the strip line of the test pattern 12 for impedance measurement formed on the core layer 11 of the three-layer wiring board 30, and the measurement formed at the end of the core layer 11 using a TDR measuring instrument. As a result of measuring the impedance by contacting the probe to the end point 10a, an impedance waveform shown in FIG. 14A was obtained.
From this impedance waveform measurement result, it can be seen that the impedance value of the impedance measurement test pattern 12 formed on the core layer surface is 77.1Ω. When the allowable range is set to ± 10% with respect to the design value of 75Ω, the allowable impedance value is 67.5 to 82.5Ω, which is within the allowable range. At this point, further lamination is performed as a non-defective product (conforming product). It was.

Next, an insulating layer 31, an impedance measurement test pattern 32, a via 33, a ground land 34, a via 35, a ground layer 38, a signal land 38a, and a wiring layer region 39 are formed by a build-up process. A layer wiring board 40 was fabricated (see FIGS. 7A to 7D).
Here, the impedance measurement test pattern 32 is electrically connected to the signal terminal 15 via the via 33, and the ground land 34 is electrically connected to the ground terminal 16 via the via 35.

Next, an insulating layer 41, a ground layer 42, a signal land 42a, a via 43, a via 44, an impedance measurement test pattern 47, a ground land 48, and a wiring layer region 49 are formed by a build-up process to form a five-layer wiring. A substrate 50 was produced (see FIGS. 8A to 8D).
Here, the ground layer 42 is electrically connected to the ground terminal 16 via the via 44, and the signal land 42 a is electrically connected to the signal terminal 15 via the via 43.
When viewed from the measurement end point 10a of the five-layer wiring board 50, a parallel stripline structure of the impedance measurement test pattern 12 and the impedance measurement test pattern 32 is formed. As a result of measuring the impedance by contacting the probe to the measuring end point 10a using FIG. 14, the impedance waveform shown in FIG. 14B was obtained. This impedance waveform measurement result is a combined impedance waveform of the impedance measurement test pattern 12 and the impedance measurement test pattern 32, and the combined impedance value is 39Ω.
When the combined impedance value is Z _all , the impedance value of the impedance measurement test pattern 12 is Z ₁ , and the impedance value of the impedance measurement test pattern 32 is Z ₂ , 1 / Z _all = 1 / Z ₁ + 1 / Z since the _2, the impedance value of the in-Bee Dance measurement test pattern 12 is found to _{77.1Ω, Z 2 = (77.1 ×} 39) / (77.1-39) than, be determined by the calculation The impedance value Z ₂ of the impedance measurement test pattern 32 is 78.9Ω, and when the allowable range is set to ± 10% with respect to the design value 75Ω, the impedance allowable value is 67.5 to 82.5Ω. Since it was within the allowable range, it was within the allowable range, so at this time, further lamination was performed as a non-defective product (conforming product).

Next, the insulating layer 51, the impedance measurement test pattern 52, the signal land 52a, the via 53, the ground land 54, the via 55, the ground layer 58, the signal land 58a, and the wiring layer region 59 are formed by a build-up process. Thus, a six-layer wiring board 60 was produced (see FIGS. 9A to 9D).
Here, the impedance measurement test pattern 52 is electrically connected to the signal terminal 15 via the via 53, and the ground land 54 is electrically connected to the ground terminal 16 via the via 55.
In the six-layer wiring board 60, the impedance measurement test pattern 52 appears on the surface, and the stripline structure cannot be formed at the measurement end point 10a.

Finally, a solder resist 61 was formed to obtain a laminated wiring board 100 with measurement end points of the present invention (see FIGS. 10A to 10D).
When impedance measurement was performed, the parallel impedance was measured, and the impedance of the impedance measurement test pattern 52 could be obtained from the above equation.

It is a model top view which shows one Example of the laminated wiring board with a measurement end point of this invention. (A) is a schematic cross-sectional view of FIG. 1 taken along the line A-A ′. FIG. 2B is a schematic sectional view taken along line B-B ′ in FIG. 1. (B) is a schematic cross-sectional view of FIG. 1 taken along the line C-C ′. It is a model top view which shows the other Example of the laminated wiring board with a measurement end point of this invention. (A) is a schematic cross-sectional view of FIG. 3 taken along line A-A ′. FIG. 3B is a schematic sectional view taken along line B-B ′ in FIG. 3. FIG. 3B is a schematic sectional view taken along line C-C ′ in FIG. 3. It is explanatory drawing which shows a part of manufacturing process of the laminated wiring board with a measurement end point of this invention. (A) is a schematic top view which shows a part of manufacturing process of the laminated wiring board with a measurement end point of this invention. (B) is a schematic cross-sectional view taken along line A-A ′ of (a). (C) is a schematic cross-sectional view taken along line B-B ′ of (a). FIG. 4D is a schematic cross-sectional view taken along line C-C ′ in FIG. It is explanatory drawing which shows a part of manufacturing process of the laminated wiring board with a measurement end point of this invention. (A) is a schematic top view which shows a part of manufacturing process of the laminated wiring board with a measurement end point of this invention. (B) is a schematic cross-sectional view taken along line A-A ′ of (a). (C) is a schematic cross-sectional view taken along line B-B ′ of (a). FIG. 4D is a schematic cross-sectional view taken along line C-C ′ in FIG. It is explanatory drawing which shows a part of manufacturing process of the laminated wiring board with a measurement end point of this invention. (A) is a schematic top view which shows a part of manufacturing process of the laminated wiring board with a measurement end point of this invention. (B) is a schematic cross-sectional view taken along line A-A ′ of (a). (C) is a schematic cross-sectional view taken along line B-B ′ of (a). FIG. 4D is a schematic cross-sectional view taken along line C-C ′ in FIG. It is explanatory drawing which shows a part of manufacturing process of the laminated wiring board with a measurement end point of this invention. (A) is a schematic top view which shows a part of manufacturing process of the laminated wiring board with a measurement end point of this invention. (B) is a schematic cross-sectional view taken along line A-A ′ of (a). (C) is a schematic cross-sectional view taken along line B-B ′ of (a). FIG. 4D is a schematic cross-sectional view taken along line C-C ′ in FIG. It is explanatory drawing which shows a part of manufacturing process of the laminated wiring board with a measurement end point of this invention. (A) is a schematic top view which shows a part of manufacturing process of the laminated wiring board with a measurement end point of this invention. (B) is a schematic cross-sectional view taken along line A-A ′ of (a). (C) is a schematic cross-sectional view taken along line B-B ′ of (a). FIG. 4D is a schematic cross-sectional view taken along line C-C ′ in FIG. It is explanatory drawing which shows a part of manufacturing process of the laminated wiring board with a measurement end point of this invention. (A) is a schematic top view which shows a part of manufacturing process of the laminated wiring board with a measurement end point of this invention. (B) is a schematic cross-sectional view taken along line A-A ′ of (a). (C) is a schematic cross-sectional view taken along line B-B ′ of (a). FIG. 4D is a schematic cross-sectional view taken along line C-C ′ in FIG. It is explanatory drawing which shows an example of the measuring method of an impedance. It is explanatory drawing which shows the example of arrangement | positioning of a signal terminal and a ground terminal. (A) And (b) is explanatory drawing which shows an example of an impedance measurement waveform. (A) And (b) is explanatory drawing which shows an example of an impedance measurement waveform.

Explanation of symbols

10a, 10b, 10c, 10d ... Measurement end point 11 ... Core layers 12, 24, 27, 32, 44, 47, 52 ... Impedance measurement test patterns 12a, 17, 22a, 27a, 32a, 36a, 38a, 42a, 44a, 47a, 52a, 58a ... Signal lands 13, 18, 22, 36, 38, 42, 58 ... Ground layers 14, 23, 24, 33, 35, 37, 43, 44, 46, 53 55 ... via 15 ... signal terminal 15a ... lead 19, 29, 39, 49, 59 ... wiring layer region 20 ... double-sided wiring boards 21, 21a, 21b, 31, 31a, 31b, 41, 41a, 41b, 51 ... Insulating layers 25, 28, 34, 45, 54 ... Ground for land 30 ... Three-layer wiring board 40 ... Four-layer wiring board 50 ... Five-layer wiring board 61, 62 ... Dah resist 100, 200 ...... measurement endpoints with laminated wiring board

Claims (5)

A multilayer wiring board in which a plurality of wiring layers, an impedance measurement test pattern, and a ground layer are formed on one side or both sides of a core layer via an insulating layer, and the test patterns facing each other in the laminating direction are electrically connected to each other. In addition, the ground layers facing each other in the stacking direction are electrically connected, the impedance measurement test pattern and the ground layer are not electrically connected, and an end point for impedance measurement is provided at one end of the core layer. In the region where the measurement end point of the core layer is not stacked, the measurement end point protrudes from the wiring layer region ,
By laminating each insulating layer and each wiring layer of the multilayer wiring board in a predetermined order, the impedance measurement test pattern of each wiring layer becomes a stripline structure in order, and impedance measurement from the measurement end point A laminated wiring board with end points for measurement, characterized in that The measurement end point includes a signal terminal and a ground terminal, wherein the signal terminal is electrically connected to an impedance measurement test pattern, and the ground terminal is electrically connected to a ground layer. Item 8. A laminated wiring board with end points for measurement according to Item 1. The laminated wiring board having a one-area layer with respect to the core layer, the measurement end points are provided at two positions of the end portion of the core layer. Multilayer wiring board. In the laminated wiring board laminated on both sides with respect to the core layer, the measurement end points are provided at four locations at the end of the core layer, two of which are laminated wiring on one surface with respect to the core layer. The laminated wiring board with a measuring end point according to claim 1 or 2, wherein the remaining two places are for impedance measurement of the laminated wiring on the other surface with respect to the core layer. 5. The method of manufacturing a multilayer wiring board according to claim 1, wherein a probe is brought into contact with the measurement end point when the impedance measurement test pattern has a stripline structure. A method for manufacturing a laminated wiring board with a measuring end point, characterized in that a laminated wiring board is manufactured while measuring and confirming that the impedance value is within an allowable range.

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