JP2006179551A - Wiring structure and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wiring structure which is capable of changing the length of the parts of through-vias covered with conductors based on wiring information and signal information as to a wiring layer, and to provide its manufacturing method. <P>SOLUTION: In the wiring structure, the parts of the through-vias covered with a conductor are changed in length based on wiring information and signal information as to the wiring layer. Concerning the through-via which is provided to the wiring layer and unable to transmit signals if it is influenced by signal delay caused by a margin, a cutting part is provided so as to shorten the margin in length. Concerning the certain through-via which is able to transmit signals even if it is influenced by signal delay caused by the margin, a cutting part is provided so as to make the margin large enough in length not to cause disconnection to the wiring layer. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a wiring structure and a manufacturing method of the wiring structure, and more particularly to a wiring structure having a counterbore provided in a through via and a manufacturing method of the wiring structure.

  FIG. 1 shows a conventional printed wiring board. The printed wiring board 1 having a multilayer structure is provided with through vias 3 for connecting the surface and each layer. The through via 3 has a branch portion 5 that is divided into a stub 4 and a wiring layer 2. Therefore, the signal transmitted through the through via 3 from the surface of the printed wiring board 1 is divided into a signal transmitted to the wiring layer 2 and a signal transmitted to the stub 4 at the branch 5. The signal transmitted to the stub 4 is reflected at the end of the stub 4 and returns to the branch portion 5. Due to this returned signal, a waveform rounding occurs in the signal transmitted to the wiring layer 2 and a signal delay occurs. Further, depending on the capacitance of the stub 4, the waveform transmitted to the wiring layer 2 may be rounded, resulting in signal delay. Particularly in the high frequency region, signal delay due to waveform rounding is likely to occur, so that transmission of a high frequency signal by the through via 3 has been difficult.

  In order to solve the above-mentioned problems, there is a technique in which a counterbore 21 is formed in a stub by an NC machine or the like as shown in FIG. The technique disclosed in Patent Document 1 forms a counterbore in a stub from a wiring layer to a depth of 0.1 mm in all through vias.

Special table 2003-521116 gazette

  Referring to FIG. 3, in the conventional method of forming a counterbore in the stub including the technique disclosed in Patent Document 1, the counterbore is formed in the stub 4 by the NC machine 31. In general, since the NC machine 31 is provided with a counterbore based on the distance from the stage 33, the thickness of the printed wiring board 1, the thickness of the dummy plate 32, the origin error of the NC machine 31, and the drill bit Due to the variation, it is difficult to form a counterbore in the through via 3 with high accuracy. Due to these factors, the counterbore may reach the wiring layer 41 as shown in FIG. The occurrence of the disconnected portion 42 has a problem that the yield of the printed wiring board is lowered.

  It is an object of the present invention to change the depth of a counterbored hole for each through via 3 in accordance with the wiring information of the connected wiring layer or the signal information of the signal to be transmitted, thereby penetrating the hole that needs to be formed with high accuracy. An object of the present invention is to provide a wiring structure and a method of manufacturing the wiring structure that can reduce the probability of occurrence of a disconnection portion while keeping the via 3 to the minimum necessary.

In order to achieve the above object, a wiring structure of the present invention is a wiring structure having a first wiring layer and a second wiring layer, and connects the first wiring layer and the surface of the wiring structure. A first hole having an inner wall surface covered with a conductor to a first length determined based on wiring information of the first wiring layer or signal information of a signal transmitted through the first wiring layer; And connecting the wiring layer to the surface of the wiring structure and covering with a conductor to a second length determined based on the wiring information of the second wiring layer or the signal information of a signal transmitted through the second wiring layer. And a second hole having a broken inner wall surface.

  In another wiring structure of the present invention, the wiring information includes wiring length information or wiring width information of the wiring, or material information of the wiring structure.

  Furthermore, another wiring structure of the present invention is characterized in that the signal information includes signal frequency information.

  According to another wiring structure of the present invention, a first wiring, a first via hole connected to the first wiring, having a first cutting portion and a first margin portion, and the first wiring A second wiring that is longer than the first wiring, and a second via hole that is connected to the second wiring and has a second cutting portion and a second margin portion. The margin portion is longer than the second margin portion.

  Further, according to another wiring structure of the present invention, the first margin portion has a length that includes an influence of the first margin portion included in a margin of a signal transmitted through the first wiring, and the first wiring portion. It has a length that does not cause disconnection.

  Further, another wiring structure of the present invention is a wiring structure having a wiring layer having wiring and having a plurality of the wiring layers, and the inner wall surface is electrically conductive to connect the wiring layer and the surface of the wiring structure. A hole covered with a body, and the hole has a portion not covered with a conductor having a length determined based on wiring information of the wiring layer or signal information of a signal transmitted through the wiring layer. It is characterized by being.

  Furthermore, another wiring structure of the present invention is characterized in that the wiring information includes wiring length information or wiring width information of the wiring, or material information of the wiring structure.

  In another wiring structure of the present invention, the signal information includes signal frequency information.

  In order to solve the above problems, a method for manufacturing a wiring structure according to the present invention includes a wiring layer having a wiring layer, and an inner wall surface covered with a conductor in order to connect the wiring layer and the surface of the wiring structure. A method for manufacturing a wiring structure comprising: determining a length of a conductor covered with the conductor on the inner wall surface of the hole based on wiring information of the wiring layer or signal information of a signal to be transmitted And a conductor removing step of removing the conductor based on the length determined in the conductor length determining step.

  In another wiring structure manufacturing method of the present invention, the conductor length determination step includes a step of performing a simulation using the wiring information and the signal information as parameters.

  Further, according to another wiring structure manufacturing method of the present invention, the conductor length determined in the conductor length determination step is a length in which an influence of the conductor is included in a margin of a signal transmitted through the wiring layer. In addition, the length is such that the wiring layer is not disconnected in the conductor removing step.

  In another wiring structure manufacturing method of the present invention, the wiring information includes wiring length information or wiring width information of the wiring, or material information of the wiring structure.

  Furthermore, in the method for manufacturing a wiring structure according to another aspect of the invention, the signal information includes signal frequency information.

  In another wiring structure manufacturing method of the present invention, a wiring layer having a wiring layer having wiring and having a hole whose inner wall surface is covered with a conductor in order to connect the wiring layer and the surface of the wiring structure. A method of manufacturing a structure, comprising: an attenuation state measuring step for flowing a signal through the wiring structure and measuring an attenuation state of the signal; and a conductivity of the inner wall surface of the hole based on data measured by the attenuation state measuring step A conductor length determining step for determining a length of a portion covered with the body; and a step of removing the conductor based on the length determined in the conductor length determining step.

  According to the above-described means, the present invention changes the length of the portion covered with the conductor in each through via based on the wiring information and signal information of the wiring layer, and is affected by the signal delay due to the stub portion. However, it is possible to form a counterbore having a depth that does not cause the wiring layer to break in a through-via that can transmit a signal. As a result, it is possible to minimize the number of through-vias that need to form a counterbore with high accuracy, and to reduce the probability of occurrence of a broken portion.

  In addition, it is possible to more easily determine the length of the portion covered with the conductor by simulating the wiring information and signal information as parameters and determining the length of the portion of the through via covered with the conductor. Can do.

  In addition, the length of the portion covered with the conductor of the through via is determined by flowing a signal through the wiring structure and measuring the attenuation state of the signal, so that the length of the portion covered with the conductor is more accurate. Can be determined.

  An embodiment of a wiring structure of the present invention will be described in detail with reference to the drawings.

  Referring to FIG. 5, a wiring structure 501 according to the embodiment of the present invention is a multilayer structure, and wiring layers 502 and 503, through-vias 505 and 506 that connect the surface of the wiring structure 501 and the wiring layer 502, Through-vias 504 and 507 connecting the surface of the wiring structure 501 and the wiring layer 503 are included. Cutting portions 512 and 515 are formed in the through vias 504 and 507, respectively, and respective margin portions 508 and 511 are provided. Further, in the through vias 505 and 506, cutting portions 513 and 514 are formed, respectively, and margin portions 509 and 510 are provided. Semiconductor chips 6 and 7 are arranged on the surface of the wiring structure 501, and each exchanges signals with other components using through vias 504, 505, 506 and 507 and wiring layers 502 and 503.

  In the present embodiment, margin portions 508, 509, 510 and 511 have a margin length determined for each margin portion. Specifically, margin portions 509 and 510 have a first margin length, and margin portions 508 and 511 have a second margin length. The first margin length is longer than the second margin length.

  A method for manufacturing the wiring structure 501 according to the first embodiment of the present invention will be described in detail.

  First, the margin length determination method in the present invention will be described.

  Depending on the length of the margin length, the influence of the signal delay due to the waveform rounding caused by the margin portion on the signal transmitted through the wiring layer is determined. The longer the margin length, the greater the influence of the signal delay on the signal transmitted through the wiring layer, and the shorter the margin length, the smaller the influence of the signal delay on the signal transmitted through the wiring layer. However, even if the margin length is long, if the wiring length is short, the wiring width is wide, the dielectric loss tangent of the wiring structure material is small, or the frequency of the signal transmitted through the wiring layer is low, the signal delay due to the margin part Has a small effect on signals transmitted through the wiring layer. Therefore, when the wiring length is short, the wiring width is wide, the dielectric loss tangent of the wiring structure material is small, or the frequency of the signal transmitted through the wiring layer is low, the margin portion does not need to be very short. The margin length may be a certain length as long as transmission is possible. Therefore, in the present invention, the length of each margin portion is determined based on the wiring information of the wiring layer to which the margin portion is connected, the signal information of the signal transmitted through the wiring layer, or the wiring information of the wiring layer and the signal information of the signal. decide. If the influence of the margin portion on the signal is small based on the wiring information, signal information, or wiring information and signal information, the margin length is determined as a length that does not cause the wiring layer to be disconnected even if the cutting portion is formed. .

  Next, a method for determining the margin length based on the wiring length in this embodiment will be described with reference to the drawings.

  Referring to FIG. 6A, first, in the wiring structure 501, based on the wiring length of the wiring layer 502, the lengths of the margin portions 509 and 510 of the through vias 505 and 506 are determined as the first margin length. Further, based on the wiring length of the wiring layer 503, the lengths of the margin portions 508 and 511 of the through vias 504 and 507 are determined as the second margin length. Since the wiring length of the wiring layer 502 is a length that allows signal transmission even under the influence of signal delay due to the margin portion, the first margin length is long. At this time, the first margin length is a length that does not cause the wiring layer to be disconnected even if the cut portion is formed. Further, since the wiring length of the wiring layer 503 is such a length that signal transmission cannot be performed under the influence of the signal delay by the margin portions 508 and 511, the second margin length is shortened.

  Next, a method for forming a cutting portion in the through via based on the determined margin length will be described.

  A cutting part is formed by the NC machine 31 shown in FIG. The NC machine 31 stores data of a plurality of through vias that form a cutting portion having the same depth. The NC machine 31 forms a cutting portion having the same depth in the through via based on the stored data. Next, data of a plurality of through vias that form a cutting portion having another depth is stored. Based on the stored data, a cutting portion having the same depth is formed for a plurality of through vias. This process is repeated to form cutting portions for all through vias.

  Hereinafter, it will be described in detail with reference to the drawings.

  Referring to FIG. 6B, cutting portions 513 and 514 are formed in the through vias 505 and 506, respectively. Specifically, first, from the first margin lengths of the margin portions 509 and 510 of the through vias 505 and 506, the first length of the portion covered with the conductor of the through vias 505 and 506 is determined, The data is stored in the NC machine 31. The NC machine 31 forms the cutting parts 513 and 514 based on the first length of the portion covered with the stored conductor.

  Referring to FIG. 6C, cutting portions 512 and 515 are formed in the through vias 504 and 507, respectively. Specifically, first, from the second margin lengths of the margin portions 508 and 511 of the through vias 504 and 507, the second length of the portion covered with the conductor of the through vias 504 and 507 is determined. The data is stored in the NC machine 31. The NC machine 31 forms the cutting parts 512 and 515 based on the second length of the portion covered with the stored conductor.

  In the embodiment of the present invention, the length of the portion covered with the conductor in each through via is changed based on the wiring information and signal information of the wiring layer, and the signal is affected even by the influence of the signal delay by the margin portion. In the penetrating via that can transmit, a cutting portion having a depth that does not cause the wiring layer to be disconnected is formed. As a result, it is possible to minimize the number of penetrating vias that need to form the cutting portion with high accuracy, and to reduce the probability of occurrence of a broken portion.

  In the present embodiment, the margin lengths of the margin portions connected to the same wiring are the same length, but they may be different lengths.

  In the present embodiment, the wiring structure having two wiring layers has been described. However, a cutting portion can be formed in the same manner as the above-described procedure for a wiring structure having three or more wiring layers. In this case, a cutting portion is formed so that the margin portion is shortened for a wiring layer in which signal transmission cannot be performed under the influence of the signal delay due to the margin portion. For wiring layers that can transmit signals even if they are affected by signal delay due to the margin, a margin length that does not cause the wiring layer to break is determined, and each wiring layer has a different depth. The cut part is appropriately formed.

  In the present embodiment, the margin length is determined, and the cutting portion is formed based on the length of the portion covered with the conductor of the through via determined from the margin length. Alternatively, the depth of the cutting portion may be determined based on the wiring information and the signal information, and the cutting portion may be formed.

  Next, a second embodiment of the present invention will be described.

  Regarding the method for determining the margin length, in the first embodiment, the margin length is determined based on the wiring information, the signal information, or the wiring information and the signal information, but in this embodiment, the cutting portion is formed. A signal is passed through the previous wiring structure, the degree of signal attenuation is measured, and a margin length capable of signal transmission is determined. Alternatively, a signal may be sent to the wiring structure after the cutting portion is formed, and the degree of signal attenuation may be measured. If there is a wiring layer with attenuation that does not allow signal transmission due to the signal delay due to the margin after forming the cutting part, the measurement results show that the through via connected to the wiring layer Further, the cutting portion is further formed so as to have a length capable of signal transmission even under the influence of the signal delay due to the margin portion. Since other configurations and methods are the same as those of the first embodiment, description thereof will be omitted.

  A third embodiment of the present invention will be described.

  Regarding the method for determining the margin length, in this embodiment, the material, wiring width, and line length actually used in the wiring structure are input as parameters, the degree of signal attenuation is calculated by simulation, and signal transmission is performed. Determine the possible margin length. Since other configurations and methods are the same as those of the first embodiment, description thereof will be omitted.

  Although the present invention has been described with reference to the preferred embodiments and embodiments, the present invention is not necessarily limited to the above-described embodiments and embodiments, and various modifications can be made within the scope of the technical idea. And can be implemented.

It is a figure which shows the cross section of the conventional wiring structure. It is a figure which shows the cross section of the conventional wiring structure. It is a figure which shows the operation | movement which forms a cutting part in a wiring structure. It is a figure which shows the cross section of the conventional wiring structure. It is a figure which shows the cross section of the wiring structure of the 1st Embodiment of this invention. It is a figure which shows the formation procedure of the cutting part of the wiring structure of the 1st Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wiring structure 2 Wiring layer 3 Through-via 4 Stub part 5 Branch part 6, 7 Semiconductor chip 20 Wiring structure 21 Counterbore 31 NC machine 32 Dummy plate 33 Stage 41 Wiring layer 42 Disconnected part 501 Wiring structure 502, 503 Wiring layer 504, ..., 507 Through-via 508, ..., 511 Margin part 512, ..., 515 Cutting part

Claims (14)

In a wiring structure having a first wiring layer and a second wiring layer,
The first wiring layer is connected to the surface of the wiring structure and is conductive up to a first length determined based on wiring information of the first wiring layer or signal information of a signal transmitted through the first wiring layer. A first hole having an inner wall surface covered with a body;
The second wiring layer is connected to the surface of the wiring structure and is conductive up to a second length determined based on wiring information of the second wiring layer or signal information of a signal transmitted through the second wiring layer. A second hole having an inner wall surface covered with a body;
A wiring structure characterized by comprising: The wiring structure according to claim 1, wherein the wiring information includes wiring length information or wiring width information of the wiring, or material information of the wiring structure. The wiring structure according to claim 1, wherein the signal information includes signal frequency information. A first wiring;
A first via hole connected to the first wiring and having a first cutting portion and a first margin portion;
A second wiring longer than the first wiring;
A second via hole connected to the second wiring and having a second cutting portion and a second margin portion;
The wiring structure according to claim 1, wherein the first margin portion is longer than the second margin portion. The first margin portion has a length that is influenced by the first margin portion and included in a margin of a signal transmitted through the first wiring, and a length that does not cause a disconnection in the first wiring. 5. The wiring structure according to claim 4, wherein A wiring structure having a wiring layer having wiring, the wiring structure having a plurality of wiring layers, and having a hole whose inner wall surface is covered with a conductor to connect the wiring layer and the surface of the wiring structure; The wiring structure, wherein the hole has a portion not covered with a conductor having a length determined based on wiring information of the wiring layer or signal information of a signal transmitted through the wiring layer. The wiring structure according to claim 6, wherein the wiring information includes wiring length information or wiring width information of the wiring, or material information of the wiring structure. The wiring structure according to claim 6, wherein the signal information includes frequency information of a signal. A method of manufacturing a wiring structure having a wiring layer having wiring and having a hole whose inner wall surface is covered with a conductor to connect the wiring layer and the surface of the wiring structure,
A conductor length determining step for determining a length of a portion of the hole covered with the conductor on the basis of wiring information of the wiring layer or signal information of a signal to be transmitted;
A conductor removing step of removing the conductor based on the length determined in the conductor length determining step;
A method for manufacturing a wiring structure, comprising: The wiring structure manufacturing method according to claim 9, wherein the conductor length determination step includes a step of performing a simulation using the wiring information and the signal information as parameters. The conductor length determined in the conductor length determining step is a length in which the influence of the conductor is included in a margin of a signal transmitted through the wiring layer, and the disconnection of the wiring layer in the conductor removing step is performed. The method for manufacturing a wiring structure according to claim 9 or 10, wherein the length does not occur. The method of manufacturing a wiring structure according to claim 9, wherein the wiring information includes wiring length information or wiring width information of the wiring, or material information of the wiring structure. The method of manufacturing a wiring structure according to claim 9, wherein the signal information includes frequency information of a signal. A method of manufacturing a wiring structure having a wiring layer having wiring and having a hole whose inner wall surface is covered with a conductor to connect the wiring layer and the surface of the wiring structure,
Attenuation state measuring step of flowing a signal through the wiring structure and measuring the attenuation state of the signal,
A conductor length determining step for determining a length of a portion of the hole covered with the conductor based on the data measured by the attenuation state measuring step;
Removing the conductor based on the length determined in the conductor length determining step;
A method for manufacturing a wiring structure, comprising:

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