JP4845554B2 - Multilayer wiring board and manufacturing method thereof - Google Patents

Description

  The present invention relates to a semiconductor element housing package for housing a semiconductor element, a circuit board, a multilayer wiring board used for an electronic circuit module, and the like, and more particularly, a multilayer having a differential transmission line connected to a termination resistor. The present invention relates to a wiring board.

  Conventionally, electronic components such as semiconductor elements represented by microprocessors and ASICs (Application Specific Integrated Circuits) have been mounted, and multilayer wiring boards used for electronic circuit boards and the like are required to improve information processing capabilities. As the number of semiconductor devices increases, the operation speed of semiconductor elements is increasing. In such a multilayer wiring board, signal wiring among internal wirings has been required to improve electrical characteristics such as matching of characteristic impedance and reduction of crosstalk noise between signal wirings.

  Therefore, in order to meet such demands, the wiring structure of the signal wiring is a strip line structure, and a large-area power wiring layer or ground (ground) wiring layer is formed above and below the signal wiring through insulating layers. It was. Further, in order to transmit a high-speed signal, a termination resistor is formed at the signal wiring end for the purpose of suppressing signal reflection. Usually, a chip component is used for this termination resistor, and it is connected to the signal wiring and the ground wiring on the surface of the wiring board.

  On the other hand, in order to cope with the further increase in speed of devices in recent years, a differential transmission system in which signals are transmitted with a pair of two signal wirings will be adopted instead of the conventional signal transmission system using a single signal wiring. It has become. In this differential transmission method, a non-inverted signal and an inverted signal are input to two signal wirings, respectively, and each difference is taken and regarded as one signal, so that noise is canceled out and the signal is less distorted. Can be transmitted at high speed. A termination resistor is also connected to such a differential transmission line (see Patent Document 1).

  In such a differential transmission line, if the interval between the two signal wires is widened in the middle, the electromagnetic coupling between the two signal wires becomes weak at that portion, and it is difficult to transmit a signal with little distortion. Therefore, it is necessary to keep the same distance to the end to which the termination resistor is connected. For this reason, if an end resistor of a chip component is connected to the end of the differential transmission line, the distance between the two signal wirings of the differential transmission line is narrow, so the two signal lines are short-circuited by a solder bridge or the like. It was difficult due to problems such as being easy to do.

  Also, if the distance between the two signal wirings in the differential transmission path is wide enough to match the mounting interval of the chip parts, the electromagnetic coupling between the two signal wirings is weakened, so high-speed signals are transmitted. In addition to being difficult to perform, there is a problem that the wiring board becomes large because the high-density wiring cannot be developed, and the downsizing and the low profile required for the recent electronic devices cannot be achieved.

Therefore, it is conceivable to form a resistor using a thick film method or a thin film method in the wiring substrate without mounting chip components on the wiring substrate (see Patent Document 2). Since the resistors are formed by the same thick film method and thin film method as the wiring board wiring method, the distance between the resistors can be reduced and the connection can be made without increasing the distance between the differential transmission lines. It is possible to control the differential impedance until immediately before being terminated by the terminating resistor, and high-speed signal transmission is possible.
JP 2004-356714 A JP-A-8-153602

  However, with the recent increase in speed and density of devices, the frequency of signals transmitted to the signal wiring of the multilayer wiring board on which the devices are mounted has increased, and differentials corresponding to the narrower pitch of the device connection terminals The distance between transmission lines is becoming extremely narrow. Accordingly, if the interval between the termination resistors is reduced, the parasitic capacitance between the termination resistors is increased, and the impedance of the termination resistor is significantly deviated from a desired value particularly in the high frequency band. However, there is a problem that high-speed signals cannot be transmitted.

  On the other hand, when forming the termination resistance of such a narrow pitch differential transmission line by a conventionally known method for manufacturing a ceramic multilayer wiring board, a resistor pattern is formed on the ceramic green sheet, and the ceramic green sheet laminate In manufacturing the resistor pattern, the shape of the resistor pattern protruding from the surface of the ceramic green sheet is deformed by the stacking pressure, and it is difficult to form an accurate resistor pattern.

  The present invention has been completed in order to solve the above-mentioned conventional problems, and its purpose is to suppress parasitic capacitance generated between the termination resistances of the differential transmission line layered on the multilayer wiring board, in a high frequency band. Another object of the present invention is to provide a multilayer wiring board capable of normally suppressing signal reflection.

  The multilayer wiring board of the present invention is connected to each of an insulating layer, a differential transmission line composed of first and second signal lines arranged in parallel on the insulating layer, and the first and second signal lines. First and second termination resistors, wherein the first and second termination resistors are connected to different surfaces of the upper surface and the lower surface of the differential transmission line. .

  The multilayer wiring board of the present invention is preferably characterized in that the angle formed between the side surface of the termination resistor and the surface of the insulating layer is 90 degrees or less.

The method for manufacturing a multilayer wiring board of the present invention includes a step of applying a resistor paste on a first support to form a first termination resistor pattern, and a first step in which the first termination resistor pattern is formed. Applying a ceramic slurry on the support to form a first ceramic green sheet; applying a resistor paste on the second support to form a second termination resistance pattern; Applying a ceramic slurry on the second support having the terminal resistance pattern formed thereon to form a second ceramic green sheet; and first and second supports from the first and second ceramic green sheets Removing the body, and forming a differential transmission line pattern on the first or second ceramic green sheet so as to be connected to the first termination resistance pattern and the second termination resistance pattern. First and superposing a step of forming, a first first surface terminating resistor pattern is formed in a second surface terminating resistor pattern is formed in the second ceramic green sheets of the ceramic green sheets Forming a ceramic green sheet laminate by laminating the second termination resistor pattern so as to be connected to different surfaces of the upper and lower surfaces of the differential transmission line pattern ; and firing the ceramic green sheet laminate It is characterized by having.

The method for manufacturing a multilayer wiring board according to the present invention includes a step of forming a differential transmission line pattern composed of first and second signal line patterns on a first support, and a connection to the first signal line pattern. Applying the resistor paste to form the first termination resistor pattern, applying the resistor paste on the second support to form the second termination resistor pattern, Applying a ceramic slurry on the first support having the termination resistance pattern formed thereon to form a first ceramic green sheet; and ceramics on the second support having the second termination resistance pattern formed thereon Applying a rally to form a second ceramic green sheet; removing the first and second supports from the first and second ceramic green sheets; First second termination resistor pattern the first and second termination resistor pattern by superimposing the formed surface of the surface where the terminating resistor pattern is formed and the second ceramic green sheet Nshito is, differential It is characterized by comprising a step of forming a ceramic green sheet laminate by being laminated so as to be connected to different surfaces of the upper and lower surfaces of the transmission line pattern, and a step of firing the ceramic green sheet laminate.

The method for manufacturing a multilayer wiring board according to the present invention includes a step of forming a signal line pattern serving as a differential transmission line on the first support and the second support, and the first and A step of applying a resistor paste so as to be connected to the signal line pattern on the second support to form the first and second termination resistance patterns; and the first and second termination resistance patterns are formed. Applying a ceramic slurry on the first and second supports to form first and second ceramic green sheets; and first and second supports from the first and second ceramic green sheets And a surface of the first ceramic green sheet on which the first termination resistance pattern is formed and a surface of the second ceramic green sheet on which the second termination resistance pattern is formed. A step of first and second termination resistor pattern, to form a ceramic green sheet laminate by laminating so as to be connected to different surfaces of upper and lower surfaces of the differential transmission line patterns combined ne, the ceramic green sheet laminate And a step of firing.

  According to the multilayer wiring board of the present invention, the first and second termination resistors connected to the respective signal lines of the differential transmission line composed of the first and second signal lines arranged in parallel on the insulating layer. Since the body is connected to different surfaces of the upper surface and the lower surface of the differential transmission line, even in the differential transmission line where the interval between the signal lines is narrow, the terminating resistors are not arranged adjacent to each other in parallel on the same surface. Therefore, the side surfaces of the termination resistors connected to adjacent signal lines do not face each other at a narrow interval, and the distance between the termination resistors is increased, so that the parasitic capacitance between the termination resistors can be reduced, and the high frequency Even in the band, the reflection of the signal can be normally suppressed and a high-speed signal can be transmitted.

  According to the multilayer wiring board of the present invention, in the above configuration, the angle formed between the side surface of the termination resistor and the surface of the insulating layer is preferably 90 degrees or less, so that the termination resistor connected to the adjacent signal line In the meantime, the average distance that influences the parasitic capacitance value is larger and the opposing area is smaller, so that it is possible to further reduce the parasitic capacitance value generated between the termination resistors, and to reflect the signal in the high frequency band. It is possible to further reduce the high-speed signal more effectively.

  According to the method for manufacturing a multilayer wiring board of the present invention, the surface of the first ceramic green sheet on which the first termination resistance pattern is formed and the surface of the second ceramic green sheet on which the second termination resistance pattern is formed. Are laminated to form a ceramic green sheet laminate, so that the termination resistor is connected to the upper or lower surface of the signal line of the differential transmission line, and the termination resistor connected to the adjacent signal line is A structure in which the upper and lower surfaces are connected to different surfaces can be easily achieved. Then, a resistor paste is applied on the first support to form a first termination resistance pattern, and a ceramic slurry is applied on the first support on which the first termination resistance pattern is formed. The second support in which the first ceramic green sheet is formed and a resistor paste is applied on the second support to form a second termination resistance pattern, and the second termination resistance pattern is formed. Since the second ceramic green sheet was formed by applying ceramic slurry on the body, the termination resistance pattern was buried in the ceramic green sheet and did not protrude from the surface of the ceramic green sheet, forming a ceramic green sheet laminate In this process, the shape of the termination resistor pattern is not easily deformed by the pressure at the time of stacking, and an accurate resistor is formed. It is possible.

  In addition, according to the method for manufacturing a multilayer wiring board of the present invention, it is possible to easily form a structure in which termination resistors connected to adjacent signal lines are connected to different surfaces in the vertical direction, A differential transmission line pattern composed of first and second signal lines is formed on the first support, and a resistor paste is applied so as to be connected to the first signal line. And forming a second termination resistance pattern by applying a resistor paste on the second support, and then forming a ceramic slurry on the first support on which the first termination resistance pattern is formed. Is applied to form a first ceramic green sheet, and ceramic slurry is applied to the second support on which the second termination resistance pattern is formed to form a second ceramic green sheet. Therefore, it becomes possible to form a highly accurate resistor without the shape of the termination resistor pattern being deformed, and the differential transmission line pattern is also buried in the ceramic green sheet to Since it does not protrude from the ceramic green sheet laminate due to the air gap and the gap between the two signal line patterns of the differential transmission line pattern in the process of forming the ceramic green sheet laminate, In addition, the differential transmission line pattern is not deformed due to the pressure during lamination, and the termination resistance pattern is not deformed due to the differential transmission line pattern being buried in the termination resistance pattern, thereby forming a more accurate resistor. Is possible.

  In addition, according to the method for manufacturing a multilayer wiring board of the present invention, it is possible to easily form a structure in which termination resistors connected to adjacent signal lines are connected to different surfaces in the vertical direction, A signal line pattern to be a differential transmission line is formed on the first support and the second support, and the signal line pattern is connected to the first and second supports on which the signal line pattern is formed. The resistor paste is applied so as to form the first and second terminal resistance patterns, and the ceramic slurry is applied onto the first and second supports on which the first and second terminal resistance patterns are formed. Since the first and second ceramic green sheets are formed, the terminal resistance pattern is buried in the ceramic green sheet and does not protrude from the surface of the ceramic green sheet. It is possible to form a highly accurate resistor without changing the shape of the termination resistor pattern due to the pressure during lamination in the process of forming the Mic green sheet laminate, and the differential transmission line pattern is also ceramic green. Since the ceramic green sheet laminate is embedded in the sheet and does not protrude from the surface of the ceramic green sheet laminate, the ceramic green sheet laminate resulting from the gap and the gap between the two signal line patterns of the differential transmission line pattern in the process of forming the ceramic green sheet laminate No delamination occurs, and there is no deformation of the differential transmission line pattern due to pressure during lamination and no deformation of the termination resistance pattern due to the differential transmission line pattern being buried in the termination resistance pattern. It is possible to form a more accurate resistor Furthermore, since the connection form between the signal line of the differential transmission line and the termination resistor is unified to the form in which the signal line is embedded in the termination resistor and connected, the resistance value of the termination resistor must be equalized. It becomes easy to suppress the variation of the resistance value.

  The multilayer wiring board of the present invention will be described in detail below. FIG. 1 is a diagram showing an example of an embodiment of a multilayer wiring board according to the present invention. FIG. 1 (a) is a cross-sectional view of the multilayer wiring board according to the present invention, and FIG. FIG. 1C is a cross-sectional view taken along the line AA ′ of FIG. 1B. In FIG. 1, 1 is an insulating layer, 2 is a differential transmission line, 3 is a terminating resistor, 4 is a multilayer wiring board, 5 is a ground conductor, 6 is a ground wiring layer or a power wiring layer, 7 and 8 are through conductors, 9 Is an electrode for connecting a semiconductor element, 10 is an electrode for external connection, and 11 is a signal wiring.

  In the multilayer wiring board 4 of this example, the insulating layer 1 is composed of a plurality of insulating layers 1a to 1e, which are basically formed of an insulating material having the same relative dielectric constant. The insulating layer 1 and various wiring layers may be further laminated in multiple layers.

  The multilayer wiring board 4 has a plurality of signal wirings 11, a ground wiring layer 6a, a power wiring layer 6b, and through conductors 7 and 8, and a semiconductor for connecting semiconductor elements to the upper surface of the multilayer wiring board 4 An element connection electrode 9 is formed, and the lower surface has an external connection electrode 10 for connecting the multilayer wiring board 4 on which a semiconductor element is mounted to an external wiring board.

  In FIG. 1A, a large number of signal wirings 11 are formed on an insulating layer 1d, and a large-area ground wiring layer 6a or a power wiring layer 6b facing the signal wirings 11 is formed on the insulating layers 1c and 1e. Each signal wiring 11 has a stripline structure. Moreover, the wiring width of each signal wiring 11 and the thicknesses of the insulating layers 1c and 1d interposed between the signal wiring 11 and the ground wiring layer 6a and the power supply wiring layer 6b are appropriately set so that the characteristic impedance of the signal wiring 11 can be arbitrarily set. By setting this value, it is possible to form the signal wiring 11 having good transmission characteristics. The characteristic impedance of the signal wiring 11 is set to a general 50Ω. The plurality of signal wirings 11 may transmit different electrical signals.

  The multilayer wiring board 4 of the present invention has a differential transmission line 2 composed of a pair of signal lines on the upper surface of the insulating layer 1b, and the differential transmission line 2 terminates an electrical signal input from the outside. The terminal conductor 3 is electrically connected to the ground conductor 5. The differential transmission line 2 is electrically connected to the semiconductor element connection electrode 9 through the through conductor 7 and is electrically connected to the external connection electrode 10 through the through conductor 8.

  A connecting portion between the differential transmission line 2 and the termination resistor 3 will be described in detail with reference to FIGS. 1B and 1C. FIG. 1B is a perspective view of the periphery of the termination resistor 3 on the upper surface of the insulating layer 1b in FIG. 1A from the upper surface, and FIG. 1C is the AA ′ line in FIG. It is sectional drawing which shows the part from the lower surface of the insulating layer 1b to the upper surface of the insulating layer 1a cut | disconnected by.

  The differential transmission line 2 includes a first signal line 2a and a second signal line 2b arranged in parallel on the insulating layer 1b, and is connected to each of the first signal line 2a and the second signal line 2b. The first termination resistor 3a and the second termination resistor 3b are connected to different surfaces on the upper surface and the lower surface of the differential transmission line 2. Further, the differential transmission line 2 has a microstrip line structure formed with the ground wiring layer 6a, and the line widths, line intervals, line thicknesses, and line widths of the first signal line 2a and the second signal line 2b. By appropriately setting the thickness of the insulating layer 1b interposed between the first signal line 2a and the second signal line 2b and the ground wiring layer 6a and setting the differential impedance to an arbitrary value, good transmission It becomes possible to form the differential transmission line 2 having characteristics. The differential impedance of the differential transmission line 2 is set to a general value of 100Ω.

  Since the termination resistor 3 is connected to different surfaces on the upper surface or the lower surface of the differential transmission line 2, the differential transmission line 2 in which the distance between the first signal line 2a and the second signal line 2b is narrow is also included. Since the termination resistors 3 are not arranged in parallel adjacent to each other on the same surface, the side surfaces of the termination resistors 3a and 3b connected to the adjacent signal lines 2a and 2b do not face each other at a narrow interval. Since the distance between the bodies 3a and 3b becomes long, the parasitic capacitance between the termination resistors 3a and 3b can be reduced, and the reflection of signals can be normally suppressed even in the high frequency band, and a high-speed signal can be transmitted.

  In the case where a plurality of differential transmission lines 2 are formed side by side as shown in FIG. 1, the termination resistor 3 is placed on a different surface on the upper surface or the lower surface of the differential transmission line 2 even between adjacent differential transmission lines 2. The parasitic capacitance between the terminating resistors 3 connected to the adjacent differential transmission lines 2 is reduced.

  Further, as shown in FIGS. 2A and 2B, the angle formed between the side surface of the termination resistor 3 and the surface of the insulating layer 1b is preferably 90 degrees or less. 2A is a cross-sectional view showing a portion from the lower surface of the insulating layer 1b to the upper surface of the insulating layer 1a, taken along the line AA ′ in FIG. 1B as in FIG. 1C. FIG. 2B is an enlarged view of the termination resistor 3 in FIG. Since the angle formed by the side surface of the termination resistor 3 and the surface of the insulating layer 1b, that is, the angle A in FIG. 2B is 90 degrees or less, the termination resistor 3a connected to the adjacent signal lines 2a and 2b. , 3b, the average distance that influences the parasitic capacitance value is larger and the opposing area is smaller, so that the parasitic capacitance value generated between the termination resistors 3a, 3b can be further reduced, and the high frequency band can be reduced. Can further suppress the reflection of the signal and transmit the high-speed signal more satisfactorily.

  Moreover, the cross-sectional shape of the termination resistor 3 shown in FIG. 1C and FIG. 2A is not only a square shape, a rectangular shape, or a trapezoidal shape, but also a triangular shape, a substantially semicircular shape, etc. Also good.

  Note that the ground wiring layer 6 a and the power supply wiring layer 6 b may be interchanged depending on the specifications of the multilayer wiring board 4. Further, the structure of the signal wiring 11 is not limited to the strip line structure as shown in FIG. 1A, and a microstrip line structure having no power wiring layer or ground wiring layer 6b located under the signal wiring 11 or the like. A coplanar line structure in which a power wiring layer or a ground wiring layer is formed on the insulating layer 1d so as to be insulated from the signal wiring 11 may be selected as appropriate according to the specifications required for the multilayer wiring board 4. Can be used. Similarly, the structure of the differential transmission line 2 is not limited to the microstrip line structure as shown in FIG. 1A, and an insulating layer is further provided between the insulating layers 1a and 1b, and the power supply wiring is provided on the insulating layer. A strip line structure or a coplanar line structure may be formed by forming a layer or a ground wiring layer.

  On the upper surface of the multilayer wiring board 4, not only the semiconductor element connection electrodes 9 for connecting the semiconductor elements but also passive components such as a coil inductor, a cross inductor, a chip capacitor or an electrolytic capacitor are attached to the electronic circuit. You may form the component connection electrode for comprising a module.

  The multilayer wiring board 4 of the present invention includes an electronic component storage package such as a semiconductor element storage package, an electronic component mounting substrate, a so-called multichip module or multichip package on which a large number of semiconductor elements are mounted, Or it is used as a motherboard.

  In the multilayer wiring board 4 of the present invention, the insulating layer 1 is an insulating material made of low-temperature sintered ceramics such as glass ceramics.

  The differential transmission line 2, the ground conductor 5, the ground wiring layer or power wiring layer 6, the through conductors 7 and 8, the semiconductor element connection electrode 9, the external connection electrode 10, and the signal wiring 11 are, for example, Au (gold), It is made of a metallized metal obtained by sintering a metal powder such as Ag (silver), Cu (copper), Pd (palladium), or Pt (platinum) by simultaneous firing with the insulating layer 1.

The termination resistor 3 is composed of oxides such as SnO ₂ , RuO ₂ , Ru-based composite oxides, boron compounds such as LaB ₆ , metals such as Pt, Cu—Ni alloys, Ag—Pd alloys, or mixtures thereof. The insulating glass is made of a sintered body sintered by co-firing with the insulating layer 1 and the metallized metal layer.

  The multilayer wiring board 4 in which the first and second termination resistors 3 are connected to different surfaces of the upper surface and the lower surface of the differential transmission line 2 is manufactured by a manufacturing method as shown in FIGS. Can be produced. 3 to 6 are cross-sectional views for each process showing an example of an embodiment of the method for manufacturing the multilayer wiring board 4 of the present invention, wherein 20a is a first support, 20b is a second support, and 21a is The first ceramic green sheet, 21b is the second ceramic green sheet, 22 is the differential transmission line pattern (22a is the first signal line pattern, 22b is the second signal line pattern), 23 is the termination resistor pattern (23a Is a first termination resistance pattern, 23b is a second termination resistance pattern), and 24 is a ceramic green sheet laminate.

  The manufacturing method of the multilayer wiring board 4 of the present invention shown in FIG. 3 includes the step (a) of forming a first terminal resistance pattern 23a by applying a resistor paste on the first support 20a, A step (b) of forming a first ceramic green sheet 21a by applying a ceramic slurry on the first support 20a on which the termination resistor pattern 23a is formed; and a resistor paste on the second support 20b. A step (c) of forming a second termination resistance pattern 23b by coating, and applying a ceramic slurry onto the second support 20b on which the second termination resistance pattern 23b is formed, to form a second ceramic green sheet A step (d) of forming 21b, a step (e) of removing the first and second supports 20a and 20b from the first and second ceramic green sheets 21a and 21b, (F) forming a differential transmission line pattern 22 on the second ceramic green sheets 21a and 21b so as to be connected to the first termination resistance pattern 23a and the second termination resistance pattern 23b; The surface of the first ceramic green sheet 21a on which the first termination resistance pattern 23a is formed and the surface of the second ceramic green sheet 21b on which the second termination resistance pattern 23b is formed are laminated and laminated. It has the process (g) which forms the laminated body 24, and the process of baking the ceramic green sheet laminated body 24, It is characterized by the above-mentioned.

  By adopting such a manufacturing method, the termination resistor 3 is connected to the upper surface or the lower surface of the signal line of the differential transmission line 2, and the termination resistor 3 connected to the adjacent signal line is different from the upper and lower surfaces. It is possible to easily make a structure connected to the. Then, a resistor paste is applied on the first support 20a to form the first termination resistor pattern 23a, and the ceramic slurry is formed on the first support 20a on which the first termination resistor pattern 23a is formed. Is applied to form a first ceramic green sheet 21a, and a resistor paste is applied onto the second support 20b to form a second termination resistor pattern 23b. Since the second ceramic green sheet 21b is formed by applying the ceramic slurry on the formed second support 20b, the terminal resistance pattern 23 is buried in the ceramic green sheet and protrudes from the surface of the ceramic green sheet. Therefore, it is terminated by the pressure at the time of lamination in the process of forming the ceramic green sheet laminate 24. The shape of the resistance pattern 23 is less likely to deform, it is possible to form a good termination resistor 3 precision.

  In the method of manufacturing the multilayer wiring board 4 of the present invention shown in FIG. 4, the step of forming the differential transmission line pattern 22 composed of the first and second signal line patterns 22a and 22b on the first support 20a (a ), A step (b) of applying a resistor paste so as to be connected to the first signal line pattern 22a to form the first termination resistor pattern 23a, and a resistor paste on the second support 20b A step (c) of forming a second termination resistance pattern 23b by applying a ceramic slurry on the first support 20a on which the first termination resistance pattern 23a is formed. The step (d) of forming the sheet 21a and the second ceramic green sheet 21b are applied by applying a ceramic slurry on the second support 20b on which the second termination resistance pattern 23b is formed. A step (e) of forming, a step (f) of removing the first and second supports 20a and 20b from the first and second ceramic green sheets 21a and 21b, and a step of the first ceramic green sheet 21a. A step of superposing and laminating the surface on which the first termination resistor pattern 23a is formed and the surface of the second ceramic green sheet 21b on which the second termination resistor pattern 23b is formed (step S4). g) and a step of firing the ceramic green sheet laminate.

  By adopting such a manufacturing method, the termination resistor 3 is connected to the upper surface or the lower surface of the signal line of the differential transmission line 2, and the termination resistor 3 connected to the adjacent signal line is different from the upper and lower surfaces. It is possible to easily make a structure connected to the. Then, a differential transmission line pattern 22 including first and second signal lines 22a and 22b is formed on the first support 20a, and a resistor paste is applied so as to be connected to the first signal line 22a. Then, the first termination resistance pattern 23a is formed, and the second termination resistance pattern 23b is formed by applying a resistor paste on the second support 20b, and then the first termination resistance pattern 23a is formed. A ceramic slurry is applied on the first support 20a formed to form a first ceramic green sheet 21a, and a ceramic is formed on the second support 20b on which the second termination resistor pattern 23b is formed. Since the second ceramic green sheet 21b is formed by applying rally, the shape of the termination resistor pattern 23 is not deformed in the same manner. In the process of forming the ceramic green sheet laminate 24, the differential transmission line pattern 22 is also buried in the ceramic green sheet and does not protrude from the surface of the ceramic green sheet 21. There is no gap between the two signal line patterns 22a and 22b of the differential transmission line pattern, and delamination of the ceramic green sheet laminate due to the gap does not occur, and the differential transmission line pattern 22 due to the pressure at the time of lamination This makes it possible to form the resistor 3 with higher accuracy without causing the deformation of the termination resistance pattern 23 due to the deformation and the differential transmission line pattern 22 being buried in the termination resistance pattern.

  In the method of manufacturing the multilayer wiring board 4 of the present invention shown in FIG. 5, the signal line patterns 22a and 22b to be the differential transmission lines 2 are formed on the first support 20a and the second support 20b ( a) and a first and second resistor paste is applied on the first and second supports 20a and 20b on which the signal line patterns 22a and 22b are formed so as to be connected to the signal line patterns 22a and 22b. Step (b) of forming two termination resistance patterns 23a and 23b, and applying a ceramic slurry on the first and second supports 20a and 20b on which the first and second termination resistance patterns 23a and 23b are formed (C) forming the first and second ceramic green sheets 21a and 21b, and the first and second ceramic green sheets 21a and 21b. (D) of removing the supporting bodies 20a and 20b, the surface of the first ceramic green sheet 21a on which the first termination resistance pattern 23a is formed, and the second termination resistance pattern of the second ceramic green sheet 21b And a step (e) of forming a ceramic green sheet laminate 24 by superimposing and laminating the surface on which 23b is formed, and a step of firing the ceramic green sheet laminate 24. . By adopting such a manufacturing method, the termination resistor 3 is connected to the upper surface or the lower surface of the signal line of the differential transmission line 2, and the termination resistor 3 connected to the adjacent signal line is different from the upper and lower surfaces. It is possible to easily make a structure connected to the. Then, the signal line patterns 22a and 22b to be the differential transmission line 2 are formed on the first support 20a and the second support 20b, and the first and second signal line patterns 22a and 22b are formed. The first and second termination resistor patterns 23a and 23b are formed by applying a resistor paste so as to be connected to the signal line patterns 22a and 22b on the supports 20a and 20b of the first and second terminations. Since the first and second ceramic green sheets 21a and 21b are formed by applying ceramic slurry on the first and second supports 20a and 20b on which the resistance patterns 23a and 23b are formed, the terminal resistance pattern 23a is formed.・ 23b is buried in the ceramic green sheet and does not protrude from the surface of the ceramic green sheet. It is possible to form the resistor 3 with high accuracy without the shape of the termination resistor pattern 23 being deformed by the pressure at the time of lamination in the step of forming the laminated body 24, and the differential transmission line pattern 22 Since it is buried in the ceramic green sheet and does not protrude from the surface of the ceramic green sheet, in the process of forming the ceramic green sheet laminate 24, there is no gap between the two signal line patterns 22a and 22b of the differential transmission line pattern 22. The resulting delamination of the ceramic green sheet laminate does not occur, the deformation of the differential transmission line pattern 22 due to the pressure during lamination, and the termination due to the differential transmission line pattern 22 being buried in the termination resistance pattern 23 Without the deformation of the resistance pattern 23, more It is possible to form the resistor 3 with a high degree of accuracy, and the connection form between the signal line of the differential transmission line 2 and the termination resistor 3 is a form in which the signal line is embedded in the termination resistor 3 and connected. Since they are unified, it becomes easy to equalize the resistance value of the termination resistor 3, and it becomes easy to suppress variations in the resistance value.

  The manufacturing method of the multilayer wiring board 4 of the present invention shown in FIG. 6 is the first and second that becomes the differential transmission line 2 on both the first and second supports 20a and 20b in the manufacturing method shown in FIG. Both signal line patterns 22a and 22b are formed. For this reason, the surface of the first ceramic green sheet 21a on which the first termination resistance pattern 23a is formed and the surface of the second ceramic green sheet 21b on which the second termination resistance pattern 23b is formed are overlapped. By laminating and forming the ceramic green sheet laminate 24, the signal line patterns overlap each other, the thickness of the signal line pattern can be increased, and the differential transmission pattern 22 with low resistance can be formed. Further, since the opposing area of the two signal wirings forming the differential transmission line 2 increases, the electromagnetic coupling between the two signal wirings becomes stronger and suitable for higher-speed signal propagation.

  Of the manufacturing method of the present invention, the characteristic differential transmission line 2 and the terminating resistor 3 and the manufacturing method of the upper and lower insulating layers 1a and 1b have been described. Each process of the manufacturing method will be described in detail.

  The support 20 is a polyolefin-based, polyester-based, polyamide-based, polyimide-based, or vinyl chloride-based resin molded body, and is a film having a thickness of 15 to 100 μm. A release layer is formed on at least the surface of the support to which the ceramic slurry is applied. As a kind of mold release agent, it can divide roughly and can use a silicone type, a fluorine type, a long-chain alkyl group containing type, an alkyd resin type, a polyolefin resin type, etc. From the viewpoint of heat resistance, releasability and cost, a silicone system is desirable.

  The resistor paste is prepared by uniformly dispersing a resistor powder obtained by adding an organic binder, a solvent, and a dispersant as necessary, and mixing them with a kneading means such as a ball mill, a three-roll mill, or a planetary mixer. .

The resistor powder used for the resistor paste is an oxide powder such as SnO ₂ , RuO ₂ , Ru-based composite oxide, boron compound powder such as LaB ₆ , metal powder such as Pt, Cu—Ni alloy, Ag—Pd alloy, etc. Or a mixture thereof and insulating glass powder. The types of resistors and glasses used, and the mixing ratio thereof are determined by electrical characteristics such as the resistance value required for the termination resistor 3, TCR (Temperature Coefficient of Resistance), and simultaneous firing. It is appropriately selected depending on the firing temperature of the ceramic green sheets 21a and 21b.

Examples of the Ru-based composite oxide include CaRuO ₃ , SrRuO ₃ , BaRuO ₃ and Bi ₂ Ru ₂ O ₇ .

  When the metal powder is an alloy powder such as an Ag—Pd alloy, an Ag—Pd alloy may be used, or a mixture of Ag powder and Pd powder in a predetermined ratio so as to be alloyed by firing, plating Alternatively, powder obtained by coating one metal powder with the other metal film by vapor deposition or the like may be used.

In addition, when a non-metal such as an oxide and a metal are included, a metal powder coated with a non-metal is used to uniformly disperse the metal and the non-metal, thereby stabilizing the resistance value of the termination resistor 3. It is good to make it. For example, when an SnO ₂ coating layer is formed on Pt powder, Sn is oxidized by forming a Sn coating layer on the surface of Pt powder by plating or vapor deposition, and then performing heat treatment at 100 to 150 ° C. in the atmosphere. Then, SnO ₂ can be used.

  The insulating glass material is not particularly limited in composition, such as boron-based, bismuth-based, zinc-based, and lead-based materials, but those having a softening temperature equal to or lower than the firing temperature of the ceramic green sheets 21a and 21b are used. .

Further, a TCR adjusting agent is added according to the TCR required for the termination resistor 3. In general, often used metal _{oxides, MnO, MnO 2, Mn 3} O 4, MoO 3, TiO 2, Fe 2 O 3, Cr 2 O 3, Sc 2 O 3, V 2 O 5, Nb 2 O ₅ , WO ₃ , SnO ₂ , CeO ₂ , Eu ₂ O ₃ , Gd ₂ O ₃ , Tb ₄ O ₇ , Ho ₂ O ₃ , Er ₂ O ₃ , Tm ₂ O ₃ , Yb ₂ O ₃ , Lu ₂ O ₃ , CuO, ZnO, NiO, MgO, CoO, and Ta ₂ O ₅ are selected according to the type of resistor powder and the required TCR. The amount added is about 1 to 10% by mass with respect to the resistor powder.

  The resistor powder and TCR adjuster powder used in the resistor paste are preferably particles having a uniform particle size and a nearly spherical shape. This is for obtaining a resistor in a uniform sintered state.

  As the organic binder used for the resistor paste, those conventionally used for the resistor paste can be used. For example, acrylic (acrylic acid, methacrylic acid or their ester homopolymer or copolymer, specifically Acrylic ester copolymer, methacrylic ester copolymer, acrylic ester-methacrylic ester copolymer, etc.), polyvinyl butyral, polyvinyl alcohol, acrylic-styrene, polypropylene carbonate, cellulose Homopolymers or copolymers such as systems.

In selecting an organic binder, acrylic and alkyd organic binders are more preferable in consideration of decomposition and volatility in the firing step. The amount of the organic binder added varies depending on the resistor powder, but may be any amount that can be easily decomposed and removed during firing and can disperse the resistor particles, and is about 5 to 20% by mass with respect to the resistor powder. Is preferred.

  The solvent used for the resistor paste is not particularly limited as long as the resistor powder and the organic binder can be well dispersed and mixed, and terpineol, butyl carbitol acetate, phthalic acid, and the like can be used.

By adding 4 to 15% by mass of the solvent to the resistor powder, the resistor paste can form the termination resistor pattern 23 by printing, and the resistor paste does not bleed after the termination resistor pattern 23 is formed. The viscosity is preferably adjusted to 30000 cps to 4000 ps. A low boiling point solvent is preferably used in consideration of the formability and drying properties after application of the resistor paste, and the boiling point of the solvent is preferably higher than the working temperature (room temperature) in consideration of the workability of application. Furthermore, in order to suppress the dimensional variation of the support 20 due to the temperature during drying, it is preferably lower than the glass transition point of the support 20. Considering these, the boiling point of the solvent used in the resistor paste is more preferably in the range of 40 ° C. to the glass transition point of the support 20. For example, when PET (polyethylene terephthalate) having a glass transition point of 70 ° C. is used as the support 20, a solvent such as methyl acetate having a boiling point of 57 ° C. may be used.

  As a method of applying the resistor paste, conventionally used printing methods such as screen printing and gravure printing can be used.

  After applying resistor paste or conductor paste, vacuum that lowers the vapor pressure of the solvent and volatilizes it, in addition to those that use radiant heat and heat transfer, such as hot air dryers and far-infrared dryers that have been used conventionally It is preferable to dry using a dryer such as a dryer. Thereby, it is possible to prevent the ceramic slurry, the resistor paste, and the conductor paste from being mixed during the subsequent application of the ceramic slurry. The drying temperature is preferably higher than the boiling point of the solvent contained in the resistor paste and lower than the glass transition point of the support. The drying method may be natural drying. The ceramic slurry may be applied without drying, but in this case, the solubility parameter (Solubility Parameter :) of the solvent and the organic binder contained in each of the ceramic slurry, the resistor paste, and the conductor paste is not mixed. It is preferable to use those having different SP values.

  The ceramic slurry is prepared by adding an organic binder and a solvent to the ceramic powder and mixing the ceramic powder while crushing it using a mixing device such as a ball mill or a bead mill. In order to adjust the dispersibility of the ceramic powder and the hardness and strength of the ceramic green sheet 21, a dispersant or a plasticizer may be added.

  As the organic binder used in the ceramic slurry, those conventionally used for green sheets can be used. For example, acrylic (acrylic acid, methacrylic acid or their homopolymers or copolymers, specifically, Is acrylic acid ester copolymer, methacrylic acid ester copolymer, acrylic acid ester-methacrylic acid ester copolymer, etc.), polyvinyl butyral, polyvinyl alcohol, acrylic-styrene, polypropylene carbonate, cellulose Homopolymers or copolymers such as In selecting the organic binder, an acrylic binder is more preferable in consideration of decomposition and volatility in the firing step in addition to the solubility parameter. The amount of the organic binder added varies depending on the ceramic powder, but it may be an amount that is easy to be decomposed and removed during firing, and the ceramic powder is dispersed, and the green sheet is easy to handle and process. About 10 to 20% by mass is desirable.

  The solvent used for the ceramic slurry is added in an amount of 30 to 100% by mass with respect to the ceramic powder so that the viscosity of the ceramic slurry can be satisfactorily applied on the support 20 and about 3 cps to 100 cps. Is desirable.

  Examples of the method for applying the ceramic slurry include a doctor blade method, a lip coater method, and a die coater method. In particular, when an extrusion method such as a die coater method, a slot coater method, or a curtain coater method is used, since these are non-contact coating methods, the terminal resistance pattern 23a previously formed on the support 20 and differential transmission are used. The line pattern 22 may not be mixed with the ceramic slurry by physical force. In addition, the thickness of the ceramic green sheet 21 is formed so as to be thicker than the thickness of the termination resistor pattern 23 a and the differential transmission line pattern 22.

  The ceramic slurry applied on the support 20 is dried to form the ceramic green sheet 21. This drying is performed by using a hot air dryer or the like conventionally used, as in the case of the resistor paste or conductor paste drying method. In addition to those using radiant heat or heat transfer, such as a far-infrared dryer, a dryer such as a vacuum dryer which lowers the vapor pressure of the solvent and volatilizes it is used.

  The differential transmission line pattern 22 is formed by applying a conductor paste in a predetermined pattern shape by the same method as applying a resistor paste.

  The conductor paste is prepared by uniformly dispersing a conductor powder obtained by adding an organic binder, a solvent and, if necessary, a dispersing agent and the like by a kneading means similar to the preparation of the conductor paste.

  The conductor powder includes, for example, one or more of Au, Ag, Cu, Pd, Pt, etc. When the conductor material is two or more, two or more kinds of powders may be mixed, an alloy, It may be a powder in which two or more materials are integrated by coating or the like.

  The organic binder and solvent used for the conductor paste are the same as those used for the conductor paste, and the same method can be used for applying (and drying) the conductor paste.

  The ceramic green sheet 21 to be the insulating layers 1 c to 1 d and the ground conductor 5 other than the differential transmission line 2, the ground wiring layer or power wiring layer 6, the semiconductor element connection electrode 9, the external connection electrode 10, and the signal wiring 11. The wiring pattern is also formed in the same manner as the ceramic green sheets 21a and 21b and the differential transmission line pattern 22. That is, after the wiring pattern is formed on the support 20, the same ceramic slurry as described above may be applied to form the ceramic green sheet 21, or after the ceramic green sheet 21 is formed on the support 20. A wiring pattern may be formed. Moreover, what is necessary is just to apply | coat by the same method, using the same thing as the conductor paste for forming the differential transmission line pattern 22 for formation of a wiring pattern. For the formation of the wiring pattern to be the semiconductor element connection electrode 9 and the external connection electrode 10 in the surface layer, a conductive paste to which glass or ceramic powder is added is used in order to improve the bonding strength with the insulating layer 1 of the wiring. Also good.

  Further, the through conductors 7 and 8 that penetrate between the insulating layers 1 and electrically connect the upper and lower wirings of the insulating layer 1 are formed by punching the ceramic green sheet 21 by punching using a mold or laser processing. It is formed by filling the through hole with a conductive paste for through conductor by embedding means such as printing or press filling. In the case of the manufacturing method shown in FIG. 3, the through holes are formed and filled before the differential transmission line pattern 22 is formed on the ceramic green sheet 21. When the ceramic green sheet 21 is thick, the through-hole processing is preferable because punching processing is formed on the front and back of the ceramic green sheet 21 with no difference in the diameter of the through-holes. Forming is possible and preferable. Moreover, when processing the through-hole, the ceramic green sheet 21 may be peeled off from the support 20, but it is more preferable to keep the ceramic green sheet 21 held on the support 20 because deformation of the ceramic green sheet 20 can be prevented. The through-conductor conductor paste is produced in the same manner as the above-described conductor paste, and is adjusted to a viscosity of about 15000 cps to 40000 cps so as to be easily filled depending on the amount of the solvent and the organic binder.

  The process of forming the ceramic green sheet laminate 24 includes not only the first ceramic green sheet 21a and the second ceramic green sheet 21b shown in FIGS. 3 to 6, but also the ceramic green sheet 21 that becomes the insulating layers 1c to 1d. This is done by aligning and laminating and gluing together. As a method of bonding, for example, a method of using an adhesive in which an organic solvent and an organic binder or a plasticizer are mixed, a method of imparting adhesiveness to the organic binder in the ceramic green sheet 21 by heating, a method of pressure bonding by applying pressure, or Examples include a method performed by combining these methods. The heating and pressurizing conditions vary depending on the type and amount of the organic binder contained in the ceramic green sheet 21 to be used and the combination of the above methods, but are generally 30 to 100 ° C. and 2 to 20 MPa.

The step of firing the ceramic green sheet laminate 24 includes removal of organic components and sintering of the ceramic powder. Removal of the organic components is carried out by heating the ceramic green sheet laminate 2 4 in the temperature range of 100 to 800 ° C., decomposition of the organic component, is intended to volatilize. The firing temperature varies depending on the ceramic composition, and is performed within a range of about 800 to 1000 ° C. The firing atmosphere varies depending on the ceramic powder and the conductor material, and is performed in the air, in a reducing atmosphere, in a non-oxidizing atmosphere, or the like, and may contain water vapor in order to effectively remove organic components.

Further, if a constrained green sheet is further laminated on the upper and lower surfaces of the ceramic green sheet laminate 24 and fired, and the restraint sheet is removed after firing, it is possible to obtain a multilayer wiring board 4 with higher dimensional accuracy. Become. The constrained green sheet is a green sheet mainly composed of a hardly sinterable inorganic material that does not sinter and shrink at the firing temperature of the ceramic green sheet laminate 24 such as Al ₂ O ₃ and does not shrink during firing. In the laminate in which the constraining green sheets are laminated, the constraining green sheet that does not shrink is prevented from shrinking in the laminating plane direction (xy plane direction) and shrinks only in the laminating direction (z direction). Is suppressed.

  In addition to the hardly sinterable inorganic component, the constrained green sheet may contain a glass component having a softening point equal to or lower than the firing temperature, for example, the same glass as the glass in the ceramic green sheet 21. When the glass is softened and bonded to the ceramic green sheet 21 during firing, the bond between the ceramic green sheet 21 and the constraining green sheet becomes strong, and a more reliable restraining force can be obtained. The amount of the glass at this time may be 0.5 to 15% by mass by external addition to the inorganic component that is a combination of the hardly sinterable inorganic component and the glass component. Firing shrinkage is suppressed to 0.5% or less.

  Examples of the method for removing the constrained green sheet after firing include polishing, water jet, chemical blasting, sand blasting, wet blasting (a method of spraying abrasive grains and water by air pressure) and the like.

  On the metallized metal exposed on the surface of the multilayer wiring board 4 obtained by baking, the metallized metal is prevented from corrosion, and a connection material (Au fine wire, solder, etc.) for connecting to a semiconductor element or an external wiring board is connected. In order to improve the property, it is preferable to deposit a Ni plating layer or an Au plating layer.

(A) is sectional drawing which shows an example of embodiment of the multilayer wiring board of this invention, (b) expanded partially the connection part of a differential transmission line and a termination resistor, and was seen through from the upper surface It is a principal part enlarged view, (c) is the principal part expanded sectional view cut | disconnected by the AA 'line of (b). It is a principal part expanded sectional view which expanded the connection part of a differential transmission line and a termination resistor partially, which shows an example of embodiment in the multilayer wiring board of this invention. (A)-(e) is sectional drawing for every process which shows an example of embodiment of the manufacturing method of the multilayer wiring board of this invention. (A)-(e) is sectional drawing for every process which shows an example of embodiment of the manufacturing method of the multilayer wiring board of this invention. (A)-(e) is sectional drawing for every process which shows an example of embodiment of the manufacturing method of the multilayer wiring board of this invention. (A)-(e) is sectional drawing for every process which shows an example of embodiment of the manufacturing method of the multilayer wiring board of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Insulating layer 2 ... Differential transmission line 3 ... Terminating resistor 4 ... Multi-layer wiring board 20a ... First support body 20b ... second support 21a ... first ceramic green sheet 21b ... second ceramic green sheet 22 ... differential transmission line pattern 22a ... first The second signal line pattern 23a, the first terminal resistance pattern 23b, the second terminal resistance pattern 24, and so on.

Claims (5)

  An insulating layer, a differential transmission line composed of first and second signal lines arranged in parallel on the insulating layer, and first and second connected to each of the first and second signal lines A multilayer wiring board, wherein the first and second termination resistors are connected to different surfaces of the upper surface and the lower surface of the differential transmission line.   2. The multilayer wiring board according to claim 1, wherein an angle formed between a side surface of the termination resistor and a surface of the insulating layer is 90 degrees or less. Applying a resistor paste on the first support to form a first termination resistor pattern;
Applying a ceramic slurry on the first support on which the first termination resistance pattern is formed to form a first ceramic green sheet;
Applying a resistor paste on the second support to form a second termination resistor pattern;
Applying a ceramic slurry on the second support on which the second termination resistor pattern is formed to form a second ceramic green sheet;
Removing the first and second supports from the first and second ceramic green sheets;
Forming a differential transmission line pattern on the first or second ceramic green sheet so as to be connected to the first termination resistance pattern and the second termination resistance pattern;
The surface of the first ceramic green sheet on which the first termination resistor pattern is formed and the surface of the second ceramic green sheet on which the second termination resistor pattern is formed are overlapped to form the first and the first ceramic green sheets. Forming a ceramic green sheet laminate by laminating the second termination resistor pattern so as to be connected to different surfaces of the upper surface and the lower surface of the differential transmission line pattern ;
And a step of firing the ceramic green sheet laminate. Forming a differential transmission line pattern consisting of first and second signal line patterns on a first support;
Applying a resistor paste to be connected to the first signal line pattern to form a first termination resistor pattern;
Applying a resistor paste on the second support to form a second termination resistor pattern;
Applying a ceramic slurry on the first support on which the first termination resistance pattern is formed to form a first ceramic green sheet;
Applying a ceramic slurry on the second support on which the second termination resistor pattern is formed to form a second ceramic green sheet;
Removing the first and second supports from the first and second ceramic green sheets;
The surface of the first ceramic green sheet on which the first termination resistor pattern is formed and the surface of the second ceramic green sheet on which the second termination resistor pattern is formed are overlapped to form the first and the first ceramic green sheets. Forming a ceramic green sheet laminate by laminating the second termination resistor pattern so as to be connected to different surfaces of the upper surface and the lower surface of the differential transmission line pattern ;
And a step of firing the ceramic green sheet laminate. Forming a signal line pattern to be a differential transmission line on the first support and the second support;
Applying a resistor paste on the first and second supports on which the signal line pattern is formed so as to be connected to the signal line pattern to form first and second termination resistor patterns; ,
Applying a ceramic slurry on the first and second supports on which the first and second termination resistor patterns are formed to form first and second ceramic green sheets;
Removing the first and second supports from the first and second ceramic green sheets;
The surface of the first ceramic green sheet on which the first termination resistor pattern is formed and the surface of the second ceramic green sheet on which the second termination resistor pattern is formed are overlapped to form the first and the first ceramic green sheets. Forming a ceramic green sheet laminate by laminating the second termination resistor pattern so as to be connected to different surfaces of the upper surface and the lower surface of the differential transmission line pattern ;
And a step of firing the ceramic green sheet laminate.

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