JP2009141247A - Method of manufacturing electronic component mounting substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing an electronic component mounting substrate which ensures bonding reliability in manufacturing a mounting substrate where thermosetting resin containing solder particles is used as a solder joint material. <P>SOLUTION: The method of manufacturing an electronic component mounting substrate performing double-sided mounting of a first electronic component 6 and a second electronic component 7 on a substrate 1 includes: a first reflow step for performing solder joint of the first electronic component 6; and a second reflow step for performing solder joint of the second electronic component after the first step, wherein curing reaction of thermosetting resin is progressed such that the curing reaction rate falls in a range of 10%-75% immediately after remelting of a first solder joint 5a1. Consequently, abnormal shape of the solder joint caused by inhibition of free expansion of remolten solder is prevented and reliability of a solder joint can be ensured. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electronic component mounting board manufacturing method for manufacturing a mounting board by mounting electronic components on a board.

As a method for mounting an electronic component such as a semiconductor chip, a solder bonding method is widely used. As a solder bonding method, a solder bonding material in which solder particles are contained in a thermosetting resin is used (for example, see Patent Documents 1 and 2). In this method, the solder bump of the electronic component is landed on the electrode and then the substrate is heated, so that the solder bonding between the solder bump and the electrode is the same as the thermosetting of the resin adhesive containing the thermosetting resin as a component. Performed in the heating process. According to this method, there is an advantage that it is not necessary to provide the reinforcing resin portion forming step as an independent step.
JP-A-11-186334 JP 2004-260131 A

  However, when the electronic component mounting method using the solder bonding material is applied to a process of manufacturing a mounting substrate by mounting a large number of electronic components on the substrate, the first surface side component in the double-sided mounting substrate, etc. There is a case where the first reflow for the solder joint is completed and the solder joint once formed is heated again at the second reflow for the solder joint of other parts such as the second surface side parts.

  In such a case, the solder joint portion formed by solidifying the once melted solder is heated again above the liquidus temperature and fluidized by remelting at the second reflow. At this time, in the resin part for reinforcement formed so as to cover the solder joint part, when the curing reaction of the thermosetting resin has already progressed considerably, at the time of solder melting in the second reflow, The resin portion covers the solder joint portion with a certain level of strength. That is, in this state, the resin portion prevents free expansion of the molten solder at the solder joint portion, and the molten solder flows out from the gap between the resin portion and the terminal, or voids in the resin portion due to the outflow of solder. In some cases, such as the occurrence of soldering, an abnormal shape of the solder joint may be induced to reduce joint reliability.

  Therefore, the present invention provides an electronic component mounting board manufacturing method capable of ensuring bonding reliability in the manufacturing of a mounting board performed using a thermosetting resin containing solder particles as a solder bonding material. Objective.

An electronic component mounting board manufacturing method according to the present invention is an electronic component mounting board manufacturing method for manufacturing a mounting board in which a first electronic component and a second electronic component are electrically connected to a board having a first electrode and a second electrode. The first electronic component is mounted on the substrate in a state in which a solder bonding material containing solder particles in a thermosetting resin is interposed between the first electrode and the terminal of the first electronic component. A one-component mounting step, and a substrate on which the first electronic component is mounted is heated to melt and solidify the solder particles, thereby forming a first solder joint that joins the first electrode and the terminal of the first electronic component. And a first reflow step of forming a first resin portion that covers the first solder joint by advancing a curing reaction of the thermosetting resin, and the second electrode and the second after the first reflow step. A state in which the soldering material is interposed between terminals of an electronic component A second component mounting step of mounting the second electronic component on the substrate, and heating the substrate on which the second electronic component is mounted to melt and solidify the solder particles, thereby the second electrode and the second electronic component. And a second reflow step of forming a second resin portion that covers the second solder joint by advancing a curing reaction of the thermosetting resin. In the second reflow step, the first calorific value and the second calorific value obtained by measuring the uncured thermosetting resin and the thermosetting resin in the middle of the curing reaction by the differential scanning calorimeter, respectively. The curing reaction rate defined by the value obtained by dividing the difference between the first calorific value and the second calorific value by the first calorific value using the amount is represented by the first solder joint. Immediately after melting, the range is 10% to 75%. So that the inner, to advance the curing reaction of the thermosetting resin of the first resin portion.

  According to the present invention, in the second reflow step, the curing reaction of the thermosetting resin proceeds so that the curing reaction rate is in the range of 10% to 75% immediately after the first solder joint is remelted. Therefore, it is possible to prevent the shape abnormality of the solder joint caused by hindering the free expansion of the remelted solder and to ensure the reliability of the solder joint.

  Next, embodiments of the present invention will be described with reference to the drawings. 1 and 2 are process explanatory views showing a method for manufacturing an electronic component mounting board according to an embodiment of the present invention, and FIG. 3 is a heating in a reflow process in the method for manufacturing an electronic component mounting board according to an embodiment of the present invention. FIG. 4 is a diagram showing a profile, and FIG. 4 is an explanatory diagram of a solder joint failure in a conventional method for manufacturing an electronic component mounting board.

  First, a method for manufacturing an electronic component mounting board will be described. 1 and 2 show a method of manufacturing a mounting substrate in which a first electronic component and a second electronic component are electrically connected to a substrate having a first electrode and a second electrode in order of steps. In FIG. 1A, a wiring circuit 2 and a second electrode 4 are formed on a first surface 1a and a second surface 1b of a substrate 1, respectively. The inner end of the wiring circuit 2 serves as a first electrode 2a for connecting a terminal of the first electronic component. A solder resist 3 is formed in advance on the first electrode 2a in an arrangement / shape surrounding the formation range of the solder joint with the terminal of the electronic component.

  Next, as shown in FIG. 1B, a solder bonding material 5 in which solder particles 5a are contained in a thermosetting resin 5b having an active action of removing an oxide film of solder is screen-printed on the first electrode 2a. Or by a method such as application by a dispenser. Here, Sn solder particles containing 3.0% Ag and 0.5% Cu are used as the solder particles 5a, and a bisphenol A type epoxy resin is used as the thermosetting resin 5b. ) As an onium salt.

  Thereafter, as shown in FIG. 1 (c), the chip-type first electronic component 6 having terminals 6a at both ends of the substrate 1 in a state where the solder bonding material 5 is supplied to the first electrode 2a. Installed. That is, the first electronic component 6 is mounted on the substrate 1 with a solder bonding material containing solder particles 5a in the thermosetting resin 5b interposed between the first electrode 2a and the terminal 6a of the first electronic component 6. (First component mounting process).

Next, the substrate 1 on which the first electronic component 6 is mounted is sent to the reflow apparatus. Here, as shown in FIG. 1D, the substrate 1 on which the first electronic component 6 is mounted is heated to melt and solidify the solder particles 5a in the solder bonding material 5, so that the first electrode 2a and the first electrons A first solder joint portion 5a1 for joining the terminal 6a of the component 6 is formed. At the same time, the curing reaction of the thermosetting resin 5b is advanced to form the first resin portion 5b1 that covers the first solder joint portion 5a1 with the gel-like resin (first reflow step). At this time, the flow caused by excessively spreading the molten solder is restricted by the solder resist 3 formed on the first electrode 2a, and the first of the first shape having an appropriate shape.
Solder joint 5a1 is formed. Note that the solder resist 3 is not indispensable, and the solder resist 3 may not be formed if there is no risk of trouble due to solder flow.

  Thereafter, the substrate 1 after the first reflow process is sent to the component mounting apparatus in a posture in which the front and back surfaces are reversed and the second surface 1b faces upward. Next, as shown in FIG. 2A, the solder bonding material 5 shown in FIG. 1 is supplied to the second electrode 4 provided on the second surface 1b. Thereafter, as shown in FIG. 2 (b), the chip-type second electronic component 7 having terminals 7a at both ends of the substrate 1 in a state where the solder bonding material 5 is supplied to the second electrode 4 is formed. Installed. That is, the second electronic component 7 is mounted on the substrate with the solder bonding material 5 containing the solder particles 5a in the thermosetting resin 5b interposed between the second electrode 4 and the terminal 7a of the second electronic component 7. 1 is mounted (second component mounting step).

  Next, the substrate 1 on which the second electronic component 7 is mounted is sent again to the reflow apparatus. Here, as shown in FIG. 2C, the substrate 1 on which the second electronic component 7 is mounted is heated to melt and solidify the solder particles 5a in the solder bonding material 5, so that the second electrode 4 and the second electron A second solder joint 5a2 that joins the terminal 7a of the component 7 is formed. At the same time, the curing reaction of the thermosetting resin 5b is advanced to form the second resin portion 5b2 that covers the second solder joint portion 5a2 with the gel-like resin (second reflow step).

  After the second reflow process, the substrate 1 is sent to the curing device, and the first resin portion 5b1 and the second solder joint covering the first solder joint portion 5a1 formed on the first surface 1a and the second surface 1b, respectively. The second resin portion 5b2 covering the portion 5a2 is heated again to further advance the curing reaction of the thermosetting resin 5b (resin curing step). Thereby, the electronic component mounting substrate 10 in which the first electronic component 6 and the second electronic component 7 are electrically connected to the substrate 1 having the first electrode 2a and the second electrode 4 is completed. In the resin curing step, the substrate is formed at a temperature at which the first solder joint portion 5a1 and the second solder joint portion 5a2 formed by melting and solidifying the solder particles 5a in the first reflow step and the second reflow step are not remelted. 1 is heated. Here, the curing temperature is set to 205 ° C. with respect to the Sn-based solder (melting point 217 ° C.) having the above composition.

  In the electronic component mounting board manufacturing method described above, the first reflow process, the second reflow process, the first resin part 5b1, and the second resin part for soldering the first electronic component 6 and the second electronic component 7 respectively. The substrate 1 is heated three times in the resin curing step for curing 5b2. That is, the thermosetting resin 5b in the solder bonding material 5 supplied for soldering the first electronic component 6 is finally cured through three heating cycles, and the second electronic component 7 is soldered. Therefore, the thermosetting resin 5b in the solder bonding material 5 supplied to be finally cured through two heating cycles.

  In the manufacturing method of the electronic component mounting board shown in the present embodiment, the occurrence of defects in the mounting board manufacturing process is achieved by rationally controlling the progress of the curing reaction of the thermosetting resin 5b in the three heating cycles described above. Is to be suppressed as much as possible. That is, in the second reflow step, the curing reaction rate indicating the degree of progress of the curing reaction of the thermosetting resin 5b is in the range of 10% to 75% immediately after the first solder joint 5a1 is remelted. Thus, the curing reaction of the thermosetting resin 5b is advanced. In the resin curing step performed after the second reflow step, the curing reaction of the thermosetting resin 5b is advanced so that the curing reaction rate is 80% or higher (desirably 90% or higher).

In the present embodiment, the heating in the first reflow process and the second reflow process is performed by the heating profile shown in FIG. Here, a heating pattern in which the temperature is raised and lowered in a short time from normal temperature to the maximum heating temperature (265 ° C.) is adopted for Sn solder having a melting point Mp of 217 ° C. That is, the melting point M
After reaching the maximum heating temperature exceeding p and surely melting the solder particles 5a in the solder bonding material 5, the temperature is rapidly lowered to room temperature. At this time, the heating time t for maintaining the heating temperature at 100 ° C. or higher is 3 min. By controlling the heating so as to be less than, the heating duration time is prevented from being delayed more than necessary. Thereby, it is possible to prevent the curing reaction of the thermosetting resin 5b from proceeding more than necessary, and it is possible to keep the curing reaction rate in the first reflow process and the second reflow process within the aforementioned range.

  Here, the definition of the curing reaction rate will be described. A thermosetting resin such as an epoxy resin is cured by a polymerization reaction caused by heating of a polymer structure constituting the resin. The degree of progress of this curing reaction is determined by performing DSC (differential scanning calorimetry) for uncured thermosetting resin and thermosetting resin in progress of curing reaction. In other words, differential scanning calorimetry was performed for each of the uncured thermosetting resin and the thermosetting resin in the course of the curing reaction with a differential scanning calorimeter, and the calorific value measurement result for the uncured thermosetting resin ( The first calorific value Q1) and the measurement result of the calorific value of the thermosetting resin in which the curing reaction is in progress, that is, the thermosetting resin that is the measurement target for determining the degree of progress of the curing reaction (second calorific value) Q2) is determined.

  Next, the ratio R (R) obtained by dividing the difference between the first heat generation amount Q1 and the second heat generation amount Q2 by the first heat generation amount Q1 using the measured first heat generation amount Q1 and the second heat generation amount Q2. = (Q1-Q2) / Q1) is determined, and the curing reaction rate of the thermosetting resin in which the curing reaction is in progress is defined by a value indicating this ratio in percentage. When the measurement target for determining the degree of progress of the curing reaction is an uncured state, the first heat generation amount Q1 and the second heat generation amount Q2 are equal, so the curing reaction rate is 0%, and the degree of progress of the curing reaction. In the case where the measurement target for obtaining is a completely cured state in which the thermosetting reaction has completely proceeded, the second calorific value Q2 is 0, so that the curing reaction rate is 100%.

  That is, in the present embodiment, the curing reaction rate indicating the degree of progress of the thermosetting reaction of the thermosetting resin 5b is determined based on the uncured thermosetting resin and the thermosetting resin that is in the process of proceeding with the differential scanning calorimeter. Using the first calorific value Q1 and the second calorific value Q2 obtained by measuring each of the above, the difference between the first calorific value Q1 and the second calorific value Q2 is divided by the first calorific value. The ratio R (R = (Q1-Q2) / Q1) is defined by a value expressed as a percentage. In addition, since the thermosetting reaction of the thermosetting resin 5b is prescribed | regulated by the kind and compounding quantity of a hardening | curing agent mix | blended with the thermosetting resin 5b, heating conditions (maximum heating temperature and heating duration), etc., it is the above-mentioned hardening. The reaction rate can be controlled by selecting a curing agent, setting the blending ratio, and heating profile.

  The significance of setting the curing reaction rate thus defined as described above will be described with reference to Table 1. Table 1 shows the relationship between the curing reaction rate of the thermosetting resin in the second reflow process, the component behavior in the second reflow process, the solder behavior, and the connection reliability after the resin curing process. Table 1 shows the curing reaction rate when the above-mentioned second reflow process is executed by using the heating profile shown in FIG. 3 using a plurality of types of solder bonding materials, and the after-curing conditions (205 ° C./heating duration time) shown in Table 1. 30 minutes (however, for Experimental Examples 7 and 8, 5 minutes and 60 minutes, respectively)) The final curing reaction rate measurement results when the resin curing step was executed, and in each case, in the second reflow step The results of evaluating the component behavior, the solder behavior in the second reflow process, and the connection reliability after the resin curing process are summarized in one table.

Here, as described above, as the solder bonding material 5, the solder particles 5a containing Sn-based solder containing 3.0% Ag and 0.5% Cu as the components are thermally cured using the bisphenol A type epoxy resin as the components. The composition mixed in the functional resin 5b is used. Here, an onium salt as a curing agent (activator) is added to the epoxy resin at six different blending ratios, whereby six types of solder bonding materials 5 are prepared. Experimental example 1 to experimental example 8 are used. The numerical value indicating the composition of the solder bonding material 5 used in each experimental example indicates the blending ratio of the thermosetting resin, the solder particles, and the curing agent in weight ratio. The blending ratio of the thermosetting resin and the solder particles is 100: 300 in any of the experimental examples, and the blending ratio of the curing agent is 0.01, 0.05 for each of Experimental Examples 1 to 6. , 0.1, 0.5, 1 and 2 are set. In Experimental Examples 7 and 8, a solder bonding material having a curing agent blending ratio of 0.05 is used as in Experimental Example 2, and in Experimental Examples 7 and 8, the after-curing conditions for the solder bonding material having the same composition are used. This was done to confirm the effect of changing the.

  In the measurement of the curing reaction rate when the above-described second reflow process is performed using these six kinds of solder bonding materials 5, 5, 10, 53, 75, 82 for each of Experimental Examples 1 to 6. , 90 (%) measurement value is obtained. That is, the result of increasing the curing reaction rate is obtained by increasing the blending ratio of the curing agent. When calculating these curing reaction rates, differential scanning calorimetry is performed using a measurement sample that is taken out of the reflow apparatus and rapidly cooled after reaching the melting point temperature of the first solder joint 5a1 in the second reflow step. For differential scanning calorimetry, a differential scanning calorimeter (model DSC 6220) manufactured by Seiko Instruments Inc. is used.

  And about the measurement sample after a 2nd reflow process, the measurement of the cure reaction rate at the time of performing the resin hardening process on the above-mentioned after-cure conditions is performed. As measurement results, measured values of 70, 80, 90, 95, 97, 98, 72, and 89 (%) are obtained for each of Experimental Examples 1 to 8. That is, in Experimental Example 1 to Experimental Example 6 in which the blending ratio of the curing agent was increased, the curing reaction rate was increased by increasing the blending ratio of the curing agent as described above. Moreover, in Experimental Examples 2, 7, and 8 in which the heating duration was changed for the solder joint material in which the curing agent was blended at the same blending ratio, a result in which the curing reaction rate increased as the heating duration increased was obtained. Yes.

  And the evaluation result about the connection reliability after the component behavior in the 2nd reflow process calculated | required about Experimental example 1-Experimental example 8, the solder behavior in a 2nd reflow process, and a resin hardening process is as follows. First, as to the component behavior in the second reflow process, as indicated by * 1, the first resin portion 5b1 has progressed to the extent that it is required to be cured, and the electronic components are normally joined after the second reflow process. A case where it is recognized that the first resin part 5b1 is not cured is insufficient, the first resin part 5b1 flows during the second reflow process (re-reflow), and the parts are displaced or dropped. Is evaluated as x evaluation. As can be seen from Table 1, in Example 1 where the curing reaction rate is 5%, x evaluation is given, but in the case where the curing reaction rate is increased to 10% or more, it is evaluated as ○ in any of the experimental examples. Is obtained. In other words, the curing reaction rate of 10% is such that the first resin part 5b1 does not drop the first electronic component 6 at such a strength that the first electronic component 6 does not drop immediately after the first solder joint 5a1 is remelted in the second reflow process. It has significance as a lower limit value for allowing bonding.

In addition, in the solder behavior in the second reflow process, as indicated by * 2, the case where the solder is normally wet and the first solder joint portion 5a1 having a normal shape is recognized to be formed is evaluated as o. Is evaluated as x evaluation when it is recognized that the protrusion protrudes abnormally from the first solder joint portion 5a1. That is, as shown in the failure example in the prior art of FIG. 4, when the curing reaction of the first resin portion 5b1 proceeds beyond the appropriate range, the first solder joint portion 5a1 has melted in the second reflow process. Immediately after that, the first resin portion 5b1 is already hard enough to inhibit the free expansion of the solder. As a result, the expanded molten solder flows out from a portion that tends to bulge out, such as the interface with the terminal 7a, so that the solder bulging portion 8 is formed. At the same time, in the first solder joint portion 5a1, since the solder volume is reduced by the amount of the molten solder that has flowed out, there occurs a void 9 in which no solder exists within the range enclosed by the first resin portion 5b1. There is.

  As can be seen from Table 1, in Examples 5 and 6 where the curing reaction rate is 82% and 90%, x is given, but when the curing reaction rate is reduced to 75% or less, the experimental example 2-Evaluation in Example 4 is good. That is, the curing reaction rate of 75% has a significance as an upper limit value for normal solder behavior in the second reflow process and for preventing free expansion of the solder. In Experimental Example 1, since the part behavior in the second reflow process is evaluated as x and the subsequent process cannot be executed, the evaluation result on the part behavior in the second reflow process is not obtained.

  And in connection reliability after the resin curing process, as shown in * 3, the case where the standard of the specified reliability test is met is evaluated as ○, and the case where an open defect occurs in the drop test or heat cycle test. × Evaluated. In the experimental results shown in Table 1, evaluations were obtained for Experimental Examples 2 to 6 and Experimental Example 8, and in the range where the experiment was effectively performed, only for Experimental Example 7 with a curing reaction rate of 72%. Evaluation is attached.

  Summarizing the above experimental results, among the experimental examples 1 to 8 shown in Table 1, in the range indicated by the chain line frame [1], the evaluation results of * 1 and * 2 are both evaluated as ◯. That is, the soldering reaction rate of the solder bonding material 5 is such that the curing reaction rate (10% to 75%) shown in the range included in the chain line frame [1] is realized immediately after the first solder bonding portion 5a1 is remelted in the second reflow process. It can be seen that by setting the composition and the heating profile, good results can be obtained for both the component behavior and the solder behavior in the second reflow process.

  In addition, for the range indicated by the chain line frame [2], the evaluation results of * 3 are all ◯ evaluations. In other words, the composition of the solder joint material 5 and the after-cure conditions are set so that the curing reaction rate (80% or more) shown in the range included in the chain line frame [2] is realized in the resin curing process performed after the second reflow process. It can be seen that the bonding reliability of the final product after the resin process is ensured.

  Therefore, in the manufacturing method of the electronic component mounting substrate shown in the present embodiment, based on the knowledge obtained from the above experimental results, in the second reflow process, the curing reaction rate defined as described above is the end of heating. The curing reaction of the thermosetting resin 5b is caused to proceed so as to be within the range of 10% to 75%. Further, in the resin curing step executed after the second reflow step, the curing reaction of the first resin portion 5b1 and the second resin portion 5b2 is advanced so that the curing reaction rate becomes 80% or more.

  In addition, in the experimental example shown in Table 1, although the example which evaluated the component behavior and the solder behavior only for the 2nd reflow process is shown, the result about the component behavior among the experimental results obtained here is The first reflow process can also be applied. That is, in the first reflow process, the curing reaction of the thermosetting resin 5b is advanced so that the curing reaction rate after the end of the reflow process is 10% or more. Thereby, it is possible to prevent a problem that the first electronic component 6 is displaced due to the flow of the first resin portion 5b1 before the transition from the first reflow process to the second reflow process.

In the above embodiment, the heating reaction rate shown in FIG. 3 is applied to the solder bonding material 5 having the composition shown in Table 1 so that the curing reaction rate in the reflow process is within the above range. The present invention is not limited to such an embodiment, and the effects of the present invention can be obtained by applying a heating profile other than the pattern shown in FIG. 3 to a solder bonding material other than the composition shown in Table 1. It is.

  That is, as shown in the experimental results of Table 1, it is qualitatively known that the curing reaction rate increases with an increase in the blending ratio of the curing agent. The same qualitative relationship holds for the case of using the curable resin. In addition, regarding the heating profile, it is obvious that the curing reaction rate increases as the heating duration is increased under the condition that the temperature is raised to a predetermined temperature necessary for sufficiently melting the solder used. . Therefore, the composition and heating profile of the solder joint material are specified, and the experiment shown in Table 1, that is, the experiment for obtaining the curing reaction rate by actual measurement for the solder joint material having the designated composition is systematic or trial and error. By executing the above, it is possible to determine the composition of the solder bonding material so that the curing reaction rate in the solder bonding / resin curing step is within a desired range.

  Moreover, in the said embodiment, although the example of the double-sided mounting which each mounted the 1st electronic component 6 and the 2nd electronic component 7 in the 1st surface 1a of the board | substrate 1 and the 2nd surface 1b, respectively was shown, this invention is a double-sided mounting. The invention is not limited to mounting, and the present invention can be applied as long as a plurality of electronic components are solder-bonded to the same substrate in two steps of a first reflow process and a second reflow process.

  The method for manufacturing an electronic component mounting board according to the present invention has an advantage that the bonding reliability can be ensured in the manufacture of an electronic component mounting board performed using a thermosetting resin containing solder particles as a solder bonding material. It is useful in the field of manufacturing an electronic component mounting board in which electronic components are mounted through two reflow processes such as a double-sided mounting board.

Process explanatory drawing which shows the manufacturing method of the electronic component mounting board of one embodiment of this invention Process explanatory drawing which shows the manufacturing method of the electronic component mounting board of one embodiment of this invention The figure which shows the heating profile of the reflow process in the manufacturing method of the electronic component mounting substrate of one embodiment of this invention Explanatory drawing of solder joint failure in the conventional manufacturing method of electronic component mounting board

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Board | substrate 2 Wiring circuit 2a 1st electrode 4 2nd electrode 5 Solder joint material 5a Solder particle 5a1 1st solder joint part 5a2 2nd solder joint part 5b Thermosetting resin 5b1 1st resin part 5b2 2nd resin part 6 1st Electronic component 7 Second electronic component 10 Electronic component mounting board

Claims (4)

An electronic component mounting substrate manufacturing method for manufacturing a mounting substrate in which a first electronic component and a second electronic component are electrically connected to a substrate having a first electrode and a second electrode,
A first component mounting step of mounting the first electronic component on the substrate in a state where a solder bonding material containing a thermosetting resin containing solder particles is interposed between the first electrode and the terminal of the first electronic component. When,
The substrate on which the first electronic component is mounted is heated to melt and solidify the solder particles to form a first solder joint that joins the first electrode and the terminal of the first electronic component, and the thermosetting A first reflow step of forming a first resin portion that covers the first solder joint by advancing a resin curing reaction;
After the first reflow step, a second component mounting step of mounting the second electronic component on the substrate with the solder bonding material interposed between the second electrode and the terminal of the second electronic component;
The substrate on which the second electronic component is mounted is heated to melt and solidify the solder particles to form a second solder joint for joining the second electrode and the terminal of the second electronic component, and the thermosetting A second reflow step of forming a second resin portion that covers the second solder joint by advancing a curing reaction of the conductive resin,
In the second reflow step, a first calorific value and a second calorific value obtained by measuring the uncured thermosetting resin and the thermosetting resin in the course of the curing reaction by a differential scanning calorimeter, respectively. The cure reaction rate defined by the value obtained by dividing the difference between the first calorific value and the second calorific value by the first calorific value using the percentage is remelted by the first solder joint. A method of manufacturing an electronic component mounting board, wherein a curing reaction of the thermosetting resin of the first resin portion is allowed to proceed within a range of 10% to 75% immediately after the process.   After the second reflow step, the resin composition further includes a resin curing step in which a curing reaction of the thermosetting resin of the first resin portion and the second resin portion proceeds so that the curing reaction rate becomes 80% or more. The manufacturing method of the electronic component mounting board | substrate of Claim 1 to do.   3. The electronic component mounting board according to claim 2, wherein, in the resin curing step, the board is heated at a temperature at which the first solder joint and the second solder joint where the solder particles are melted and solidified are not remelted. Manufacturing method.   4. The electron according to claim 1, wherein in the first reflow step, a curing reaction of the thermosetting resin is advanced so that the curing reaction rate after the reflow step is 10% or more. Manufacturing method of component mounting board.

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