JP2012024834A - Solder material and method for preparing the same, and method for manufacturing semiconductor device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve impact resistance and increase joining reliability, in a solder material containing bismuth (Bi).SOLUTION: The solder material includes: a tin-bismuth (Sn-Bi) alloy; copper (Cu); and an alloy represented by X-Y; wherein X is at least a metallic element selected from a metallic element group comprising Cu, Ni, and Sn and Y is at least a metallic element selected from a metallic element group comprising Ag, Au, Mg, Rh, Zn, Sb, Co, Li and Al.

Description

  The present invention relates to a solder material, a manufacturing method thereof, and a manufacturing method of a semiconductor device using the same.

  As electronic devices such as mobile phones and digital cameras have become more sophisticated and smaller in size in recent years, semiconductor devices such as integrated circuit chips are directly flip-chip mounted on a wiring board, reducing the mounting area and making efficient use. A mode for achieving the above has been proposed. Depending on the scale of the LSI circuit, bumps (bonding protruding electrodes) may be formed over almost the entire surface on which the circuit is formed. In this case, solder is often used as the metal material of the bump, and the solder bump is melted by reflow to obtain an electrical connection between the semiconductor chip and the circuit board.

  On the other hand, Pb-free solder that does not contain Pb has been studied in place of tin-lead (Sn-Pb) based solder containing lead (Pb) that has an adverse effect on the human body while interest in global environmental protection is increasing. In particular, although Sn-Ag-Cu Pb-free solder, which has a melting point of about 40 ° C higher than Sn-Pb solder, has become widespread, there is a problem that power consumption and CO2 emissions during mounting will increase more than before. It was. In addition, problems such as a decrease in connection reliability of large and thin parts due to thermal stress and an increase in raw material cost due to high heat resistance of parts and substrates have become apparent.

In order to solve the above problems, efforts are being made to reduce thermal stress on electronic components by adding bismuth (Bi), which is a low melting point material, to solder. By including Bi in the solder alloy, in addition to lowering the melting point, the effects of increasing the mechanical strength of the solder joint structure and improving wettability can be obtained. However, if the amount of Bi increases, the effects of lift-off due to Se segregation of Bi and reduction in bonding reliability due to the brittleness of Bi will increase.

For example, as shown in FIG. 1A, when a solder material containing SnBi particles 102 and Cu particles 101 is used, Sn—Bi is liquid when the melting point of SnBi (139 ° C.) or higher is reached immediately after heating. In addition to the phase 104, a Cu—Sn alloy layer 103 is formed on the surface of the Cu particles 101 (see FIG. 1B). Thereby, melting | fusing point in a solder joint part rises to 250 degreeC or more. When the heating is further continued for melting and bonding, the fragile Bi layer 105 is segregated on the Cu—Sn alloy layer 103 in the subsequent cooling process (see FIG. 1C). In the Bi segregation layer 105, cracks 106 are likely to occur, and the impact resistance is greatly reduced.

In order to cope with this problem, a method for adjusting the amount of Bi to be added (for example, see Patent Document 1), a joining method for reducing the influence of brittleness (for example, Patent Document 2), and the like have been studied. In the method of adjusting the amount of Bi added, by setting the weight ratio of Bi to the solder alloy to 21% by weight or less, the ratio of Bi dissolved in Sn is improved in a state of being left at a high temperature. The rate decreases. Thereby, the elongation as a whole solder joint part increases, the thermal stress concerning a solder joint part is relieved, and the connection reliability of an electronic component and a circuit board improves. In addition, in the joining method for reducing the influence of brittleness, Bi and the third are added by adding at least one metal of a third element metal (Cu, Ag, Zn, In) to the Sn—Bi based solder. An intermetallic compound is formed between elemental metals to prevent cracks and Bi segregation after mounting, improve connection reliability, and reduce connection failures.

JP 2008-130697 A JP-A-11-33775

  However, the method of adjusting the Bi addition amount has a problem that the thermal fatigue strength of the solder joint structure is not good due to the brittleness of Bi itself. In particular, in a high temperature environment, the Bi structure becomes coarse, and when stress is applied to the solder joint structure, slippage occurs at the interface between the Sn and Bi structures and solder cracks are likely to occur. On the other hand, in the method of adding the third metal element, even if an intermetallic compound of Bi is formed between Bi and the third metal element, Sn in the solder and a wiring electrode (for example, a copper (Cu) electrode) If an alloy phase (Cu6-Sn5) is formed between the two layers, the Bi phase is deposited in a layer form on the alloy phase (Cu6-Sn5), so that the impact resistance such as a drop test is still insufficient.

  The present invention has been made in view of the above-described problems, and in a solder material containing Bi, a solder material capable of improving connection reliability, a manufacturing method thereof, and a semiconductor device using the same It is an object to provide a method.

In order to solve the above problem, in one aspect, the solder material includes a tin-bismuth (Sn—Bi) alloy, copper (Cu), and an alloy represented by XY, ,
X is at least one metal element selected from the metal element group consisting of Cu, Ni, and Sn;
Y is at least one metal element selected from the metal element group consisting of Ag, Au, Mg, Rh, Zn, Sb, Co, Li, and Al.

In another aspect, a method for making a solder material is provided. The method for producing the solder material is as follows:
A film or protrusion of an XY alloy is formed on the surface of the Cu particles, where X is at least one metal element selected from the metal element group consisting of Cu, Ni, and Sn, and Y is Ag, Au, Mg , Rh, Zn, Sb, Co, Li, Al, at least one metal element selected from the metal element group,
Mixing the Cu particles on which the film or protrusions of the XY alloy are formed, and a tin-bismuth alloy material,
Process.

In yet another aspect, a method for manufacturing a semiconductor device using the solder material described above is provided. That is, the above-described solder material is disposed on the electrode on the substrate,
The protruding electrode of the semiconductor element is attached to the electrode on which the solder material is arranged,
The solder material is heated and melted to join the protruding electrodes of the semiconductor element and the electrodes on the substrate.

With the solder material having the above-described configuration, the connection reliability between an object to be joined, for example, an electronic component such as a semiconductor element, and the substrate can be improved.

It is a figure for demonstrating the problem of the conventional SnBi type solder joint. It is a schematic diagram for demonstrating the basic composition of an Example. It is a schematic diagram for demonstrating the basic composition of an Example. It is the schematic which shows the manufacturing process of Cu particle | grains which have XY alloy protrusion. It is the schematic which shows the manufacturing process of Cu particle | grains which have XY alloy protrusion. It is the schematic which shows the manufacturing process of Cu particle | grains which have XY alloy protrusion. It is the schematic which shows the manufacturing process of Cu particle | grains which have XY alloy protrusion. It is the schematic which shows the manufacturing process of Cu particle | grains which have XY alloy protrusion. It is a schematic sectional drawing which shows mounting of the semiconductor element using the solder material of an Example. It is a table | surface which shows distribution of the connection resistance change rate of the semiconductor device which has the solder joint structure of an Example with a comparative example.

  2 and 3 are schematic views illustrating the basic configuration of the solder material 10 of the embodiment. In the embodiment, the solder material 10 includes three kinds of metals: a Cu material 11, an alloy material 12 including tin-bismuth (Sn—Bi), and an XY alloy 16. In the XY alloy 16, the metal X is at least one metal selected from Cu, Ni, and Sn. The metal Y is at least one metal element selected from the group consisting of Ag, Au, Mg, Rh, Zn, Sb, Co, Li, and Al. The metal material contained in X and Y is a metal that can incorporate (diffuse) Bi into the XY alloy at the eutectic temperature to form the XY-Bi eutectic.

  The XY alloy 16 is, for example, spherical or scaly particles as shown in FIG. In this case, the XY alloy particles 16 can be mixed with SnBi particles 12 and Cu particles 11 which are the other two materials to form a powdery solder material. Alternatively, a binder or flux may be added to these materials to form a paste solder material. Such a solder material 10 is applied to an object to be joined at the time of solder joining, and heated and melted to constitute a joint portion. It can also be used as a material for solder bumps.

  Immediately after the heating of the solder material 10, as shown in FIG. 2B, SnBi having a low melting point becomes a liquid phase 14, and Sn contained in the SnBi particles 12 reacts with Cu on the surface of the Cu particles 11. A Cu—Sn alloy layer 13 is formed. XY alloy particles 16 are interposed between the Cu particles 11 having the Cu—Sn alloy layer 13 formed on the surface. The XY alloy is an arbitrary combination selected from the above-mentioned X and Y, and examples thereof include Cu-18Ag, Cu-2.3Al, Cu-10Zn, 85Cu-5Sn-4Zn-1Ni.

  When further heated and melt-bonded from this state, in the subsequent process, Bi is finely dispersed in the XY alloy 16 as shown in FIG. 2C, and a ternary alloy (XY-Bi) is obtained. ) Particles 17 are formed. As an example, when Cu—Ag alloy particles 16 are used as the XY alloy particles 16, a Cu—Ag—Bi alloy is formed, and a Cu—Ag—Bi alloy layer 17 is deposited between the Cu particles 11. Thereby, the segregation of the fragile Bi phase on the Cu-Sn layer 13 on the surface of the Cu particles 11 can be reduced. In addition, since the Cu-Ag-Bi alloy layer (eutectic composition) 17 is interposed between the Cu particles 11, even if a crack 16 occurs in Bi segregated on Cu-Sn, the Cu-Ag-Bi alloy layer. 17 functions as a stopper, and the progress of cracks can be prevented. With this configuration, the impact resistance of the joint is improved.

  The eutectic alloy represented by XY-Bi is not limited to a ternary system, but is an N-based system alloy (X is a first metal element, Y is a second metal element, and N is 3 or more). . For example, in the case where 97Cu-1Zn-2Ni alloy particles 16 are formed using Cu and Ni as the first metal X and Zn as the second metal Y, Cu-Zn-Ni- A quaternary eutectic composition of Bi is obtained.

  The shape of the XY alloy 16 is not limited to the method of forming it in a spherical shape or a scale shape as shown in FIG. 2 and mixing it in the solder material 10, but also on the surface of the Cu particles 11 as shown in FIG. You may form as the processus | protrusion 26 or a porous pattern. Alternatively, as shown in FIG. 3B, the same effect can be obtained even when the XY alloy is configured as an XY alloy film 36 that covers the Cu particles 11. When the projections 26 are formed of an XY alloy (for example, Cu-Ag alloy) as shown in FIG. 3A, bismuth (Bi) 27 in the material is precipitated near the roots of the Cu-Ag projections 26, and the ternary It becomes easy to form the Cu-Ag-Bi alloy 29 of the system. This configuration has a higher effect of suppressing Bi segregation compared to the case where Bi precipitates randomly in the mixed material of FIG. As shown in FIG. 3B, when the Cu particles 11 are covered with the Cu—Ag alloy layer 36, the Cu—Sn layer is hardly formed and the segregation of Bi is suppressed. Further, Bi27 is taken into the Cu-Ag alloy film 36 at the eutectic temperature to form the Cu-Ag-Bi alloy layer 39, so that the segregation of Bi is suppressed.

  In Example 1, Cu particles having a projection or porous XY alloy layer formed on the surface thereof as shown in FIG. 3A are used as a solder material, which is mixed with SnBi particles to form a bonding material (solder). Material). An Sn-15Ag alloy is selected as the XY alloy. More specifically, Cu particles having Sn-15Ag protrusions formed on the surface are prepared, and this is mixed with Sn-58Bi solder alloy particles and a flux to prepare a conductive paste material. Sn-58Bi particles have a particle size of 10 to 25 μm and a weight ratio of 40 wt%. Cu particles on which Sn-15Ag alloy is formed have a particle size of 25 to 45 μm and a weight ratio of 50 wt%. The flux content of the conductive paste material is 10 wt%.

  4 to 8 are schematic diagrams for explaining a method of forming a protruding Sn-15Ag alloy on Cu particles of a core material (core material). First, as shown in FIG. 4, a silane compound 32 is prepared. A first organic functional group 33 is formed at one end of the silane compound 32. The first organic functional group is at least one of functional groups such as a thiol group, a phenyl group, an amine group, and an amino group. For example, a hydroxyl group (not shown) is formed as the second organic functional group at the other end of the silane compound 32. The silane compound 32, inorganic fine particles 31 or organic fine particles 31, and Cu particles 11 are mixed and dispersed in a solvent. Here, the inorganic fine particles 31 are used. By mixing and dispersing in the solvent, the inorganic fine particles 31 and the hydroxyl groups (not shown) of the silane compound 32 react to bond the inorganic fine particles 31 to the silane compound 32.

  As the inorganic fine particles 31, for example, non-conductive inorganic particles such as silica (SiO2) and alumina (Al2O3) are used, but glass particles, various ceramic particles, and FRP (fiber reinforced plastic) particles may be used. The size of the inorganic fine particles 31 is preferably 10 μm or less, particularly preferably 1 μm or less. When organic fine particles are used, non-conductive organic particles such as polymethyl methacrylate, melamine, urethane, urea, benzoguanamine, polyethylene, and polystyrene can be used. The size of the organic fine particles 31 is preferably 10 μm or less, and particularly preferably 1 μm or less. The silane compound 32 may use a titanium or aluminum coupling agent. As the second organic functional group, a compound containing at least one of a vinyl group, an epoxy group, a nitro group, a methacryl group, an amino group, a mercapto group, an isocyanato group, and a carboxyl group in addition to a hydroxyl group may be used.

  When the inorganic fine particles (or organic fine particles) 31 to which the organic functional group 33 has been added and the Cu particles 11 are mixed and dispersed in a solvent, as shown in FIGS. 5 (A) and 5 (B), the inorganic fine particles (or Organic fine particles) 31 are attached to and bonded to the surface of the Cu particles 11 serving as the core. The shape of the Cu particles 11 is not particularly limited, and various shapes such as a spherical shape, a granular shape, a lump shape, a crushed shape, a porous shape, an agglomerated shape, a flake shape, a spike shape, a filament shape, a fiber shape, and a whisker shape are used. Of particles can be used. In general, it is desirable to use a true spherical powder having a uniform particle size as much as possible from the viewpoint of reducing variation in electric conductivity when used. The size of the Cu particles 11 is preferably 100 μm or less, particularly preferably 50 μm or less when a solder material for flip chip mounting is used. In the embodiment, the Cu particles 11 having a particle size of 25 to 45 μm are used as described above. .

  Although the inorganic fine particles 31 are randomly deposited on the surface of the Cu particles 11, the density at which the inorganic fine particles 31 adhere to the Cu particles 11 is controlled by adjusting the temperature of the solution, the content of the silane compound, the reaction time, and the like. It is possible to deposit at least a part of the surface of the Cu particles 11, preferably 1% to 50%.

  Next, as shown in FIG. 6, for example, by performing electroless plating using the inorganic fine particles 31 attached and bonded to the surface of the Cu particles 11 as a mask, the gap between the inorganic fine particles 31, that is, the exposed surface of the Cu particles 11. Then, an XY plating metal layer 41 is grown. The XY plating metal is, for example, Sn-15Ag. Instead of the electroless plating method, the surface may be coated by a known method such as sputtering or vapor deposition.

  Next, as shown in FIG. 7, the inorganic fine particles 31 are removed with an inorganic acid such as hydrofluoric acid. When organic fine particles are used, the organic fine particles 31 on the surface of the Cu particles 11 are removed by etching with an organic solvent such as acetone. As a result, as shown in FIG. 8 (A), a crater-like protrusion 46A of Sn-15Ag alloy or a spike-like protrusion 46B as shown in FIG. 8 (B) remains on the surface of the Cu particle 11. In order to collect and take in Bi in the vicinity at the eutectic temperature, the length of the protrusion 41A formed on the Cu particles 11 is 10% to 50%, particularly 10% to 30% of the diameter of the conductive particles (Cu particles) 11. % Is preferable. In order to efficiently accumulate Bi in the vicinity of the protrusions 46A and 46B made of the Sn-15Ag alloy, it is preferable that the protrusions 46A and 46B of the Sn-15Ag alloy have an appropriate specific surface area. For this reason, the length of the protrusion 45A is preferably within the above range. On the other hand, from the same viewpoint, the diameter of the base portion of the protrusion 41 </ b> B is preferably 1% to 30% of the diameter of the Cu particles 11.

  In order to form the protrusion 46 having the above length (or diameter) on the surface of the Cu particle 11, the diameter of the inorganic fine particle (or organic fine particle) 31 is 1/20 to 3/10 of the diameter of the Cu particle 11. It is desirable.

  In the examples, Cu particles 11 having protrusion-shaped Sn-15Ag alloy 46 formed on the surface are prepared, and this is mixed with Sn-Bi particles to form a solder powder, or a flux is added to form a conductive paste. As described with reference to FIG. 2, a solder material is prepared by mixing Sn-15Ag alloy particles such as spheres, scales, protrusions, and porous with Cu particles and Sn-Bi particles. May be. Further, as shown in FIG. 3B, a Sn-15Ag alloy film 36 may be formed on the surface of the Cu particles 11 by plating, sputtering, vapor deposition, or the like.

FIG. 9A and FIG. 9B are diagrams illustrating an application example in which the above-described solder material is used for manufacturing a semiconductor device. The Cu paste 11 with Sn-15Ag protrusions 46 produced as shown in FIG. 8 is mixed with Sn—Bi particles and flux to produce a conductive paste material 63. This conductive paste material 63 is applied on the electrode 62 of the printed circuit board 61 by screen printing. A semiconductor element 51 having solder bumps 53 is mounted on the printed conductive paste 63 by a chip mounter. A semiconductor device 70 in which the semiconductor element 51 is flip-chip bonded to the printed board 61 as shown in FIG. 9B is completed by solder-bonding the semiconductor element 51 and the printed board 61 using N ₂ reflow. The preheating condition at the time of joining was set to a temperature of 100 to 120 ° C. for 90 to 120 seconds, and the peak condition was set to 170 ° C. for 50 to 60 seconds. The cooling rate was 2-3 ° C./s.

  The semiconductor element 51 used in this example has a size of 8.5 mm × 8.5 mm, and has a configuration in which about 120 Sn-3Ag-0.5Cu solder bumps 53 are arranged along the periphery of the circuit formation surface. The printed board 61 is a 40 mm × 40 mm FR-4 board having Cu electrodes arranged in the same manner as the solder bumps 53 of the semiconductor element 51.

  As a result of testing the continuity of the junction 65 using a lead wiring (not shown) on the substrate 61 side of the semiconductor device 70, it was confirmed that all the junctions were conductive. Further, a drop impact test was repeated with a drop height of 1.6 m and a substrate strain of 4000 με for one cycle, and this was repeated 50 cycles, and the change in connection resistance was measured every 10 cycles. As a result, the connection resistance change rate of the junction 65 of the semiconductor device 70 of Example 1 was + 5% or less through 50 cycles as shown in the table of FIG.

  Further, as a result of the cross-sectional SEM / EPMA analysis of the solder joint portion 65, no segregation of Bi was observed on the Cu particle interface of any joint portion, and the protruding Cu-15Ag formed on the Cu particle surface It was confirmed that fine Bi was dispersed and precipitated inside.

  Instead of the Cu particles 11 having the Sn-15Ag protrusions 46 of Example 1, a conductive solder paste was prepared using a material in which the protrusions 46 were formed on the Cu particles 11 by Cu-10Zn alloy plating. As shown in FIG. 9, a semiconductor device was manufactured, and continuity measurement and a drop impact test were performed in the same manner as in Example 1. As a result, as shown in FIG. 10, the connection resistance value after 50 cycles of the drop impact test was + 5% or less.

  As a result of the cross-sectional SEM / EPWA analysis of the solder joint portion 65, no Bi segregation was observed on the Cu particle interface of the joint portion 65, and the protrusion Cu-10Zn formed on the surface of the Cu particle had a fine inside. It was confirmed that Bi was dispersed and precipitated.

(Comparative example)
The conductive paste was prepared by mixing Cu particles, Sn-Bi particles, and flux without mixing the XY alloy with the Cu particles and without mixing the XY particles. As shown in FIG. 9, a semiconductor device was manufactured, and continuity measurement and a drop impact test were performed in the same manner as in Example 1. As a result, the connection resistance value after 3 cycles of the drop impact test was 10 times that of Example 1, and the connection resistance increase rate after 10 cycles was 5 times. Further, as a result of the cross-sectional SEM / EPMA analysis of the solder joint portion 65, it was confirmed that Bi was segregated in a layered manner on the Cu particle interface of the joint portion 65, and a crack was formed at the same location.

  In this way, by mixing an XY alloy selected from a predetermined metal into Cu particles and Sn-Bi solder particles, or forming protrusions or coatings on Cu particles with an XY alloy, low temperature mounting can be achieved. It is possible to realize a solder material capable of improving the bonding reliability and yield of the semiconductor device at the same time.

The following additional notes are presented for the above explanation.
(Appendix 1)
A solder material containing a tin-bismuth (Sn-Bi) alloy, copper (Cu), and an alloy represented by XY,
X is at least one metal element selected from the metal element group consisting of Cu, Ni, and Sn;
Y is a solder material characterized in that it is at least one metal element selected from a metal element group consisting of Ag, Au, Mg, Rh, Zn, Sb, Co, Li, and Al.
(Appendix 2)
Cu is contained in the solder material in the form of particles,
The solder material according to appendix 1, wherein the XY alloy is a protrusion or a film formed on the surface of the Cu particles.
(Appendix 3)
The solder material according to appendix 2, wherein the protrusions of the XY alloy are crater-like or spike-like protrusions.
(Appendix 4)
The solder material according to appendix 3, wherein a length of the protrusion is 10% to 50% of a diameter of the Cu particle.
(Appendix 5)
The solder material according to appendix 1, wherein the tin-bismuth alloy, the Cu, and the XY alloy are mixed with the solder material in a powder state.
(Appendix 6)
X and Y take in Bi after heating and melting of the solder material to form an N-based alloy (N is 3 or more) having a eutectic composition represented by XY-Bi. The solder material according to any one of appendices 1 to 5.
(Appendix 7)
A film or protrusion of an XY alloy is formed on the surface of the Cu particles, where X is at least one metal element selected from the metal element group consisting of Cu, Ni, and Sn, and Y is Ag, Au, Mg , Rh, Zn, Sb, Co, Li, Al, at least one metal element selected from the metal element group,
Mixing the Cu particles on which the film or protrusions of the XY alloy are formed, and a tin-bismuth alloy material,
A method for producing a solder material including a process.
(Appendix 8)
The formation of the protrusions is
Attaching inorganic fine particles or organic fine particles so that at least part of the surface of the Cu particles is exposed;
Forming the XY alloy film on the exposed surface of the Cu particles using the adhered inorganic fine particles or organic fine particles as a mask;
The method for producing a solder material according to appendix 7, further comprising a step of removing the inorganic fine particles or the organic fine particles after the formation of the XY alloy film.
(Appendix 9)
The adhesion of the inorganic fine particles or organic fine particles is performed by mixing a compound in which an organic functional group is bonded to one end of a silane compound and the inorganic fine particles or organic fine particles are bonded to the other end and the Cu particles in a solvent. The method for producing a solder material according to appendix 8, which includes a step of dispersing.
(Appendix 10)
The method for producing a solder material according to appendix 9, wherein the diameter of the inorganic fine particles or the organic fine particles is 1% to 30% of the diameter of the Cu particles.
(Appendix 11)
The method for producing a solder material according to appendix 9, wherein the inorganic fine particles or the organic fine particles are attached such that 1% to 50% of the surface of the Cu particles is exposed.
(Appendix 12)
Arrange the solder material of any one of Supplementary notes 1 to 6 on the electrode on the substrate,
The protruding electrode of the semiconductor element is attached to the electrode on which the solder material is arranged,
Heating and melting the solder material to join the protruding electrode of the semiconductor element and the electrode on the substrate;
The manufacturing method of the semiconductor device characterized by including a process.

  As a solder material, it can be applied to the formation of solder bumps of semiconductor elements and solder bonding in flip chip mounting of semiconductor elements.

DESCRIPTION OF SYMBOLS 10 Solder material 11 Cu particle | grain 12 SnBi particle | grain 13 Cu-Sn alloy layer 16 XY alloy particle | grain 17 XY-Bi alloy layer (eutectic composition)
26, 46A, 46B XY alloy protrusion 31 Inorganic or organic fine particles 32 Silane compound 36 XY alloy film 51 Semiconductor element 53 Solder bump (projection electrode)
61 Printed Circuit Board 62 Electrode 63 Solder Paste 65 Joint 70 Semiconductor Device

Claims (8)

A tin-bismuth (Sn-Bi) alloy;
Copper (Cu),
A solder material including an alloy represented by XY,
X is at least one metal element selected from the metal element group consisting of Cu, Ni, and Sn;
Y is a solder material characterized in that it is at least one metal element selected from a metal element group consisting of Ag, Au, Mg, Rh, Zn, Sb, Co, Li, and Al. Cu is contained in the solder material in the form of particles,
The solder material according to claim 1, wherein the XY alloy is a protrusion or a film formed on a surface of the Cu particles.   The solder material according to claim 2, wherein the protrusion of the XY alloy is a crater-like or spike-like protrusion.   4. The solder material according to claim 3, wherein the length of the protrusion is 10% to 50% of the diameter of the Cu particles. A film or protrusion of an XY alloy is formed on the surface of the Cu particles, where X is at least one metal element selected from the metal element group consisting of Cu, Ni, and Sn, and Y is Ag, Au, Mg , Rh, Zn, Sb, Co, Li, Al, at least one metal element selected from the metal element group,
Mixing the Cu particles on which the film or protrusions of the XY alloy are formed, and a tin-bismuth alloy material,
A method for producing a solder material including a process. The formation of the protrusions is
Adhering inorganic fine particles or organic fine particles so that at least part of the surface of the Cu particles is exposed,
Forming the XY alloy film on the exposed surface of the Cu particles using the adhered inorganic fine particles or organic fine particles as a mask;
The method for producing a solder material according to claim 5, further comprising a step of removing the inorganic fine particles or the organic fine particles after the formation of the XY alloy film.   The adhesion of the inorganic fine particles or organic fine particles is performed by mixing a compound in which an organic functional group is bonded to one end of a silane compound and the inorganic fine particles or organic fine particles are bonded to the other end, and the Cu particles in a solvent. The method for producing a solder material according to claim 6, comprising a step of dispersing. A solder material according to any one of claims 1 to 4 is disposed on an electrode on a substrate,
The protruding electrode of the semiconductor element is attached to the electrode on which the solder material is arranged,
Heating and melting the solder material to join the protruding electrode of the semiconductor element and the electrode on the substrate;
The manufacturing method of the semiconductor device characterized by including a process.

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