KR20230075504A - Low-temperature solder, low-temperature solder manufacturing method and low-temperature solder coated lead wire - Google Patents

Abstract

[Purpose] The present invention relates to low-temperature soldering, a method for manufacturing low-temperature soldering, and a low-temperature solder-coated lead wire, and in low-temperature soldering composed of Sn and Bi or an alloy of Bi and In, Al, P, Sb, In It is an object of the present invention to provide a low-temperature solder capable of being soldered to electrodes (aluminum, copper, etc.) on a resin film by incorporating one or more of these and melting/alloying them, and at a low cost.
[Construction] In a base material that is Sn, Bi, In, or an alloy of Bi and In, a main material composed of one or more of Al, P, Sb, and In (excluding cases in which In is contained in the base material) is used, and the total maximum It is a low-temperature solder whose adhesion is enhanced by mixing 3 wt% or less, preferably 1.0 wt% to 1.5 wt% or less, 0.01 wt% or more, melting and alloying.

Description

Low-temperature solder, low-temperature solder manufacturing method and low-temperature solder coated lead wire

The present invention relates to low-temperature solder used for resin films used in solar cell substrates, liquid crystal substrates, and the like, methods for manufacturing low-temperature solder, and low-temperature solder-coated lead wires.

Conventionally, soldering of lead wires to electrodes such as solar cell substrates or liquid crystal substrates is more commonly used for reasons such as the strength of tin lead soldering and low price.

Further, in the case of an electrode made of aluminum or the like, since sufficient soldering strength could not be obtained, silver paste was applied and sintered, and a lead wire was soldered thereon by tin lead soldering.

Moreover, these days, the demand for lead-free soldering is becoming stronger from the viewpoints of pollution and the like.

In addition, there is a demand for forming a solar cell on a flexible resin film such as PET and soldering a lead wire to the electrode (aluminum electrode, copper electrode, etc.) at a low temperature.

Compared to tin-lead soldering, conventional lead-free soldering has problems in that its strength is slightly less than the required strength or is expensive, so that it cannot be replaced.

Further, in solar cells formed on resin films or the like, a problem that the soldering temperature is too high has arisen.

The inventors of the present invention, for low-temperature soldering composed of Sn, Bi, In, or an alloy of Bi and In, which is a type of lead-free soldering, Al, P, Sb, In (except when the base material contains In) ) up to 3 wt% in total of one or more such. Low-temperature solder, which is preferably melted and alloyed by mixing a trace amount of 1 wt% or 1.5 wt% or less, can be soldered extremely firmly to an electrode (aluminum, copper, etc.) such as a resin film. found.

Therefore, in the present invention, in low-temperature soldering composed of Sn, Bi, In, or an alloy of Bi and In, Al, P, Sb, In the main material consisting of one or more of In (excluding the case where In is contained in the base material), the total maximum of 3 wt% or less, preferably 1.0 wt% to 1.5 wt% or less, 0.01 wt% or more is mixed. It is melted and alloyed to enhance adhesion.

At this time, the melting temperature of the low-temperature solder after melting/alloying is equal to or lower than the melting temperature of the base material.

In addition, an auxiliary material made of an alloy containing at least one of Al, P, Sb, and In is incorporated into the base material as necessary to melt and alloy it.

In addition, as an alloy of sub-materials, it is intended to be an alloy of Cu and P.

Further, in the base material, Al, CuP, and, if necessary, In as the main material are incorporated in a total maximum of 3 wt% or less, preferably 1.0 wt% to 1.5 wt% or less, and 0.1 wt% or more, so that they are melted and alloyed.

In addition, the base material, the main material, and the sub-material are mixed together or divided into a plurality of parts to be melted and alloyed.

In addition, it is intended to be used for soldering lead wires to electrodes of solar cell substrates and liquid crystal substrates (resin films).

In addition, the low-temperature solder is melted and applied to the surface of the wire rod and the ribbon.

In addition, melt coating is performed in a state in which ultrasonic waves are applied.

As described above, the present invention relates to a low-temperature solder composed of Sn, Bi, In, or an alloy of Bi and In, including at least one of Al, P, Sb, and In (except when the base material contains In). Total up to 3wt%. Preferably, the low-temperature solder melted and alloyed by incorporating a trace amount of 1 wt% to 1.5 wt% or less can be soldered extremely firmly to an electrode (aluminum, copper, etc.) such as a resin film. In particular, low-temperature solder of Sn and Bi It could be manufactured very cheaply.

In addition, the melting temperature of the low-temperature solder after melting/alloying was equal to or lower than the melting temperature of the base material, so that an increase in the melting temperature due to mixing could be eliminated.

In addition, by mixing one or more of Al, P, Sb, In (except when In is included in the base material), melting and alloying to produce low-temperature solder, the adhesion strength to the soldering target can be significantly increased. could

[Fig. 1] An explanatory diagram of low-temperature solder manufacturing according to the present invention.
Fig. 2 is an explanatory diagram of the low-temperature solder material manufacturing apparatus of the present invention.
[Fig. 3] An explanatory diagram of low-temperature soldering of the lead wire of the present invention.
[Fig. 4] An explanatory diagram of the low-temperature soldering of the present invention.
[Fig. 5] is a composition example of the low-temperature solder of the present invention.
[Fig. 6] This is a trial example of the low-temperature soldering of the present invention.
[Fig. 7] An example of low-temperature soldering according to the present invention.
[Fig. 8] An example of low-temperature soldering (metal-metal) of the present invention.
[Fig. 9] An example of bonding the PET film of the present invention.
[Fig. 10] An experimental example of the low-temperature solder of the present invention.
[Fig. 11] An example of a bonding test result of the low-temperature solder of the present invention.
[Fig. 12] is an experimental example of the absence of ultrasonic output (without preheating) of the present invention.
[Fig. 13] An example of a temperature cycle test of the low-temperature solder of the present invention.

[Example 1]

1 shows an explanatory diagram of low-temperature solder manufacturing of the present invention.

Fig. 1 (a) shows a flow chart, and Fig. 1 (b) shows a material example.

In Fig. 1 (a), S1 prepares a base material and a main material. This prepares the following material shown in the material example of Fig. 1(b).

Base material: Sn42, Bi58

·Main materials: Al, GuP, In

Here, the base metal is a material (base metal) that is the basis of the alloy forming the low-temperature solder of the present invention, and, for example, Sn is 42 wt% and Bi is 58 wt% (melting temperature: 139° C.). The weight ratio of Sn and Bi is arbitrary within the range in which an alloy can be formed, for example, Bi is 3 wt% to 58 wt%, and the rest may be Sn. Which ratio should be selected appropriately so as to reach the desired value by experimenting with the melting temperature (the more Bi, the lower the temperature, and the melting temperature is 139 ° C. at 58 wt%). In addition, as for other low-temperature solders, Sn-In type, and Sn-Bi-In type, as described in Fig. 5 and the description thereof, the ratio may be appropriately selected.

In addition, the main material is a material that affects soldering, such as removal of oxide film on the surface of the object to be soldered, adhesion, hygroscopicity, flowability, and viscosity during soldering. In the present invention, the main material It is a material whose total amount is at most 3 wt% or less, preferably 1 wt% to 1.5 wt% or less, and 0.01 wt% or more. Here, one or more of Al (adhesion to a target to be soldered), P (or CuP, oxide film removal to a target to be soldered, adhesion), In (hygroscopicity, fluidity), and Sb (adhesion) is mixed to form an object to be melted and alloyed. It is a material. In addition, the total amount of the main material is at most 3 wt% or less, preferably 1 wt% to 1.5 wt% or less, and a trace amount of 0.01 wt% or more, and the melting temperature of the low-temperature solder after melting and alloying the main material is mixed with the base material. The same as or slightly lower than the melting temperature (eg, 1 ° C to 3 ° C lower). This is presumed to be that the total amount of the main material is a very small amount of up to 3 wt% or less, preferably 1 wt% to 1.5 wt% or less with respect to the base material, and enters into the skeleton of the base material to be re-skeletonized.

S2 mixes the main material with respect to the base material. This mixes the main material with the base material prepared in S1.

In S3, the base material and the main material are melted and alloyed. In S2, the main material is mixed with the base material, heated, melted, and well stirred to form an alloy. At this time, if the main material is oxidized by oxygen in the air and alloying is difficult, etc., inert gas (for example, nitrogen gas) is blown into the crucible as necessary, or a melting furnace or vacuum melting furnace filled with inert gas is used. use additional

In S4, the low-temperature solder material is completed.

By preparing a base material and a main material as described above, mixing them and melting/alloying them, the low-temperature solder (Sn-Bi-based, Sn-In-based, or Sn-Bi-In-based low-temperature solder) according to the present invention can be produced. It will be described in detail sequentially below.

Fig. 2 shows an explanatory diagram of the low-temperature solder material manufacturing apparatus of the present invention.

In Fig. 2, the solder material 1 is a base material and a main material prepared in S1 of Fig. 1, which are metal fragments (roughly pulverized) here.

The solder material input tray 2 loads the solder material 1 and puts it into the melting furnace 3.

The melting furnace 3 is for heating with a heater 4 or the like, injecting the solder material 1 into the inside, melting the base material and the main material, and stirring them to form an alloy. The melting furnace 3 melts and stirs the base material and the main material introduced into the inside in normal atmosphere to form an alloy. At this time, if necessary, inert gas (such as nitrogen gas) is blown in to reduce oxidation due to oxygen in the air, or if necessary, it is sealed and filled with inert gas (or vacuum exhausted).

As described above, the base material and the main material prepared in S1 of FIG. 1 are mixed, melted in the melting furnace 3, stirred and alloyed, and the low-temperature solder (Sn-Bi-based, Sn-In-based, Sn-Bi- Indium-based low-temperature solder) can be manufactured.

Fig. 3 shows a low-temperature soldering explanatory diagram of the lead wire of the present invention.

Fig. 3(a) shows a flow chart, and Fig. 3(b) shows an example of a substrate/lead wire.

In (a) of FIG. 3, S11 performs pre-soldering of a low-temperature solder pattern on a substrate by means of ultrasonic waves. This is, for example, a solar cell board (PET plate 0.1 mmt, etc.), a part (pattern) to be soldered from now on, and the low-temperature solder of the present invention (low-temperature solder prepared in S4 in FIG. 1) is applied to the tip of an ultrasonic soldering iron. It is supplied and melted, and ultrasonic waves are applied to solder the pattern portion on the substrate (referred to as ultrasonic pre-soldering) in advance.

S12 solders lead wires with or without ultrasonic waves. In S11, for example, the ultrasonic pre-soldered portion (pattern) on the electrode (eg, aluminum foil) of the solar cell substrate (PET plate) is applied along the lead wire or without ultrasonic waves applied thereon. The lead wire is soldered by melting the low-temperature solder of the present invention. Further, supply of solder is unnecessary when low-temperature solder is pre-soldered to the lead wire in advance.

As a result of the above, pre-soldering of the low-temperature solder of the present invention is performed on the part to be soldered (for example, the electrode part (aluminum part) of the substrate (PET plate) of the solar cell) using ultrasonic waves (S11), and the pre-soldering The electrode part (aluminum foil part) of the solar cell substrate, which is impossible to solder in the prior art, by ultrasonically soldering the lead wire using the low-temperature solder of the present invention or soldering (S12) without ultrasonic waves on the part (pattern) applied. ), etc., it is possible to pre-solder with ultrasonic waves and solder the lead wires thereon with ultrasonic soldering or without ultrasonic soldering.

In addition, ultrasonic soldering is performed at 10 W or less, usually at about 1 W to 3 W. If it is strong, the film formed on the solar cell substrate (for example, nitride film) or the crystal on the surface of the substrate is damaged, so it is not strengthened.

Figure 3(b) shows an example of the substrate/lead wire.

In FIG. 3(b), the substrate is a heat-resistant resin substrate such as PET (for example, a flexible resin substrate having a thickness of about 0.1 mm), which is extremely difficult to solder in normal soldering. Yes. The low-temperature solder that imparts the adhesion of the present invention is pre-soldered by ultrasonic waves to the portions (patterns) serving as electrodes (aluminum electrodes, copper electrodes, etc.) of these substrates. Then, the lead wire can be soldered to the board (aluminum electrode, copper electrode) by ultrasonically soldering the lead wire to this pre-soldered portion (pattern) or by soldering without ultrasonic wave.

In addition, the lead wire is a lead wire soldered to an electrode part (pattern) on a substrate using the low-temperature solder that gives the adhesion of the present invention, and the wire (circular copper wire of the present invention is soldered to the low-temperature solder A wire that has been solder-plated (ultrasonic solder plating), and it is easy to solder if it is slightly crushed into an ellipse), ribbon (a thin copper plate cut into a width of about 1 mm, and the low-temperature solder of the present invention is pre-solder plated (ultrasonic solder plating) ), and so on.

Fig. 4 shows a low-temperature soldering explanatory diagram of the present invention.

Fig. 4(a) shows an example of pre-soldering, and Fig. 4(b) shows an example of ribbon or wire soldering.

In (a) of FIG. 4, the substrate (e.g., PET sheet 0.1 mmt) 11 is an example of a solar cell substrate, and an aluminum film is formed on the entire surface of the back surface of the substrate 11, for example. (Park) (12) was formed.

The aluminum film (foil) 12 is an electrode formed by forming (adhering, evaporating, etc.) an aluminum film (foil) on the entire surface of the back surface of the illustrated substrate (PET plate) 11, which is a solar cell substrate. aluminum electrode).

The ultrasonic soldering iron tip 13 is a soldering iron tip heated while applying ultrasonic waves from an ultrasonic generator not shown.

The low-temperature solder 14 is the low-temperature solder of the present invention (the low-temperature solder produced in S4 in Fig. 1).

The soldering operation will be explained next.

(1) The substrate 11 is transferred onto a preheating table, vacuum adsorbed, fixed, and preheated (for example, preheated to about 130°C).

(2) From the starting point to the ending point of the electrode pattern (rectangular pattern) formed on the aluminum film (foil) 12, low-temperature solder 14 is automatically supplied to the illustrated ultrasonic soldering iron tip 13 and melted. While applying ultrasonic waves, the aluminum film (foil) 12 is moved at a constant speed in a state close enough not to be rubbed to form a rectangular pre-soldering pattern on the aluminum film (foil) 12.

As a result of the above, it is possible to low-temperature solder the low-temperature solder 14 of the present invention onto the aluminum film (foil) 12 in a predetermined pattern of pre-soldering.

Figure 4(b) shows an example of low-temperature soldering of a ribbon or wire.

In Fig. 4(b), the ultrasonic soldering iron tip 13-1 is a soldering iron tip that is heated with or without applying ultrasonic waves from an ultrasonic generator (not shown).

The low-temperature soldering ribbon or wire 15 is obtained by pre-soldering the low-temperature solder of the present invention to the ribbon or wire. Further, solderability is better when the wire 15 is slightly deformed into an elliptical shape.

Next, a soldering operation for the pre-soldering pattern portion of the ribbon or wire will be described.

(1) The substrate 11 is preheated as in FIG. 4(a).

(2) Regarding the ribbon or wire 15 with low-temperature solder disposed along the portion of the pre-soldering pattern formed on the aluminum film (foil) 12 portion on the upper (rear surface) of the substrate 11, with or without ultrasonic waves, from above While lightly pressing with the soldering iron tip 13-1, it is moved at a constant speed in the right direction in the drawing to melt the solder of the low-temperature soldering ribbon or wire 15 and solder it to the pre-soldering pattern portion.

As a result, the ribbon or wire 15 pre-soldered with the low-temperature solder 14 of the present invention can be soldered to the pre-soldering pattern portion on the aluminum film (foil) 12.

In addition, the quality of the soldering with ultrasonic waves or the soldering without ultrasonic waves of the present invention is that the ribbon or wire is subjected to ultrasonic soldering or ultrasonic-less soldering to the part to be soldered, and the force of pulling the ribbon or wire to break the board or the like (Bending force, about 2 to 5 Kg), it is judged as good when it is not peeled off from the substrate or the like by pulling with a force slightly weaker, and when it is peeled off, it is judged as bad.

5 shows a composition example of the low-temperature solder of the present invention.

In FIG. 5, the base material and the main material are the distinction between the base material and the main material described in FIG.

The composition example is the composition example of the parent material and the main material.

The wt% example is an example of the wt% of the composition of the parent material and the main material.

The wt% range is an example of the range of wt% of the composition of the base material and the main material.

As shown in Figure 5, the composition example, wt% example, wt% range.

parent material main ingredient Remarks (example of melting point)

Cho Sung-rye Sn-Bi alloy Al P Sb In Melting Point: Yes 139°C

(Excluding cases where In is included in the base material)

Sn-In alloy Melting Point: Yes 120℃

SnBi-In alloy Melting Point: Yes 90℃

wt%yes Sn Bi In Al CuP8 Sb In

42 58 -- 0.5 0.5 0.5 0.5

52 - 48 0.5 0.5 0.5 0.5

A A/2 A 0.5 0.5 0.5 0.5

wt% range 0.1 trace amount 0.1 0.1

| |(P) | |

1.0 0.1 1.0 1.0

Total amount: maximum 3wt%, preferably 1.0wt%-1.5wt% below

Here, as a composition example, Sn42wt% and Bi58wt% in the city were used as base materials in the trial production. In addition, the composition range may be stable within a range in which low-temperature solder alloys (Sn-Bi-based, Sn-In-based, and Sn-Bi-In-based solder alloys) can be created, for example, Sn-Bi-based The solder alloy may contain 3 wt% to 58 wt% of Bi and the balance of Sn, and may be appropriately selected through experiments by actually measuring the melting temperature of the prepared low-temperature solder alloy (base material).

There are Al.P (or CuP8), In, Bi, Sb, etc. as the main materials, but P is an alloy of P (red phosphorus) and CuP8 at the beginning (an alloy in which P is 8wt% and the rest is Cu, the wt% of P is 8% of CuP8 Phosphate copper) was used. In the case of P, it is saturated at about 0.1 wt% (or about P = 0.16 wt% in the case of CuP8), and when added further, the viscosity increases significantly. For this reason, in normal use to ensure fluidity, hygroscopicity, etc., it is preferable to add less than saturation of P (the amount of P added is about 1/10 compared to other materials (preferably 0.1 wt% to 0.01 wt%). %) is good). Similarly, since other main ingredients tend to do the same, it is good to determine an appropriate amount of addition by experiment as necessary.

In addition, the total amount of the main material is at most 3 wt% or less, preferably 1 wt% to 1.5 wt% or less, and preferably 0.1 wt% or more. In the addition of the main material within this range, it is almost the same as or slightly lower than the melting temperature of the base material.

6 shows a trial example of the low-temperature soldering of the present invention. The illustration shows an example of one that can be used for the soldering shown in FIG. Those that cannot be used are omitted.

6, the base material of the low-temperature solder (low-temperature solder manufactured in S4 of FIG. 1) of the present invention is

・Sn52/In48 (melting point: 120℃)

・Sn42/Bi58 (melting point: 139℃)

・Sn48/Bi52 (melting point: )

· Four types of Sn40/In40/Bi20 (melting point: 90°C) were used.

Metal materials of Al, CuP8, and In (0.5 wt% each) were used as the main materials. CuP8 used phosphide copper with 8 wt% P and the rest Cu.

Sample No is the number of the starting sample.

Regarding the above prototype samples, only good ones were described by ultrasonic soldering and non-ultrasonic soldering of FIG. 5 described above. Those that cannot be soldered are omitted. The results are shown in Figure 7.

Fig. 7 shows an example of low-temperature soldering according to the present invention. Here in Figure 7,

·Ultrasonic is a distinction between soldering with ultrasonic waves and soldering without ultrasonic waves.

내지 0.4mm

)/리본(100μｍｔ, 50μｍｔ, 30μｍｔ), Si웨이퍼(0.2mmt)의 구별이다.・The object to be soldered is a material to be soldered using the low-temperature solder sample of FIG.

to 0.4 mm

)/ribbon (100 μmt, 50 μmt, 30 μmt) and Si wafer (0.2 mmt).

의 주석도금선을 납땜하고 잡아 당겼을 때에 Si웨이퍼가 깨어지는 힘(인장강도 약 1kg 내지 5kg 정도)보다 약간 약한 힘)을 나타낸다.◎ indicates the excellent adhesion of the low-temperature solder of the present invention to the object to be soldered (0.4 mm

It shows a force that is slightly weaker than the force (tensile strength of about 1 kg to 5 kg) that breaks the Si wafer when the tin-plated wire of is soldered and pulled.

의 주석도금선을 납땜하고 잡아 당겼을 때에 조금 힘을 가하면 박리되는 상태)을 나타낸다.△ is about the adhesion of the low-temperature solder of the present invention to the soldering target (0.4 mm

When the tin-plated wire of is soldered and pulled, if a little force is applied, it is peeled off).

In the above experiment of Fig. 7, it was found that sufficient soldering strength can be obtained with respect to the Al plate, Cu plate, Cu wire/ribbon, and Si wafer in the case of "with ultrasonic waves".

In addition, in the case of "no ultrasonic wave", it peeled off when pulled. When the surface of the object to be soldered was cleaned, a considerably strong adhesion was obtained in some cases, and in some cases it was not, so it was unstable.

Fig. 8 shows a soldering example (metal-metal) of the low-temperature solder of the present invention. Fig. 8(a) shows a soldering example. Here, the soldering conditions are as shown in the drawing,

・Solder melting point: about 138℃

· Maximum process temperature: 180 ° C. or less.

The low-temperature solder used was obtained by adding 0.5 wt% each of Al, CuP, and In to 42 wt% Sn and 58 wt% Bi. Also, the low-temperature soldering of other Sn-In alloys and SN-Bi alloys is the same.

In Fig. 8 (a), as shown in the figure, a sheet in which an aluminum foil is bonded to a PET base film using a Co-PET adhesive material as shown in the figure is shown. cut with Then, as shown in the drawing, the surfaces of the aluminum foil are partially overlapped vertically and soldered so that the low-temperature solder (Sn-Bi low-temperature solder) of the present invention is soldered to the overlapping portion.

As for the soldering method, for example, the upper and lower aluminum foils are pre-soldered with low-temperature solder. Further, soldering can be reliably performed by applying ultrasonic waves (ultrasonic soldering).

Then, the pre-soldered portion on the upper aluminum foil pre-soldered and the pre-soldered portion on the lower aluminum foil are overlapped as shown in the drawing, the whole is held down with a soldering iron tip from above, and the low-temperature solder is melted and soldered. At this time, ultrasonic soldering can ensure soldering.

As described above, as shown in FIG. Soldering without ultrasonic waves can also be performed, but ultrasonic soldering is preferable.

Figure 8 (b) shows an example of a photograph of soldering. These photographs show examples of photographs in which an elongated aluminum foil is placed horizontally on a PET surface and only the "soldered portion" shown in the center is ultrasonically soldered at a low temperature. In the "soldering area" shown, the aluminum foil was strongly soldered to the PET surface.

Next, using FIG. 9, the PET film bonding example of FIG. 8 will be explained in detail.

9 shows an example of bonding the PET film of the present invention.

Fig. 9(a) shows a flow chart, and Fig. 9(b) shows an explanatory diagram thereof.

In Fig. 9(a), S21 fixes the film to the sponge. As shown in (b-1) on the right, a film (for example, PET film) is fixed to a heat-resistant sponge (for example, it is fixed with a heat-resistant polyimide tape coated with an adhesive).

S22 puts enough solder on the iron tip. As shown in (b-2) on the right, the low-temperature solder of the present invention is generously attached to the iron tip.

S23 is ultrasonically soldered so that the iron tip does not close to the film.

In S24, one side of the film is turned over, and the other side of the soldering surface is overlapped. This causes the pre-soldered film sides to overlap, as shown in (b-3) on the right.

S25 cuts the copper plate to the size of the soldering area.

S26 presses the copper plate with a tip like an iron.

S27 confirms that the melted solder overflows from the tip and completes it. As shown in (b-4) on the right, when these S26 and S27 are pressed with an iron tip (with ultrasonic waves) on a copper plate with good thermal conductivity, the low-temperature solder on the pre-soldered joint surface melts and overflows from the tip. Accordingly, when the iron tip was directly brought into contact with the film, ultrasonic low-temperature soldering could be performed cleanly, as if ironing, without the film melting or becoming soft and shrinking.

Fig. 9 (c) shows examples of soldering conditions. Examples of soldering conditions in (a) and (b) of FIG. 9 are shown. Here, the following conditions were set.

·Iron tip temperature : 175℃±5℃

・Sliduck setting value : 14

Absence : Poron sponge

·Ultrasound output : 10W

Fig. 9 (d) shows a sectional view of soldering. This is a cross-sectional diagram in the case of ultrasonic low-temperature brazing of aluminum foil (Al) (ultrasonic pre-soldered) bonded to the PET surface through a polyimide tape instead of the copper plate of FIG. 9 (a). In this case, if a polyimide tape coated with an adhesive is attached so as to surround only the portion to be soldered, low-temperature soldering to unnecessary portions can be prevented.

Fig. 10 shows an experimental example of a member of the low-temperature solder of the present invention. This shows an example of soldering with and without ultrasonic waves under the conditions of Figs. 8 and 9 described above. In the low-temperature soldering of the present application, for example, the following results were obtained.

No. texture Remarks (shape, hardness, surface condition, etc.)

·3 SUS plate Low-temperature soldering is possible with preheating

(Ultrasonic soldering, the same below)

·4 cutting board Low-temperature soldering is possible without preheating

·5 MDF Same as above

·6 cork board same

·7 acrylic board Same as above

·9 EPDM Sponge Rubber same

·10 NR Sponge Rubber Same as above

·11 Poron Sponge same

·12 NR rubber sheet Low-temperature soldering is possible with preheating

It has been found that the above cellulose/resin materials can also be soldered with the low-temperature soldering of the present invention (soldering with ultrasonic waves or preheating (about 10 degrees lower than the melting temperature) if necessary).

Fig. 10(b) shows an example photograph of the member in Fig. 10(a).

Fig. 11 shows an example of a bonding test result of the low-temperature solder of the present invention. Here, the experimental results show the following.

와이어를 접합해서 300g 이상의 밀착력을 ○로 판정했다.*1: Joinability: 0.2 mm

The wire was bonded, and the adhesive force of 300 g or more was judged as (circle).

*2: US non-marking can be adhered without ultrasonic waves

*3: PET of 29 is the No. 1 candidate for Perovskite.

The metals (1 silver, 2 copper, 3 aluminum, etc.) shown in the drawing of FIG. 11 could be soldered at low temperature with or without ultrasonic waves.

In addition, inorganic materials (7 alumina, 8 barium titanate, 10 silicon carbide, 11 silicon nitride, 12 fluorite, 13 quartz, 14 ceramics, etc.) formed by firing oxides shown in the drawing of FIG. or low-temperature soldering was possible without ultrasonic waves.

In addition, the cellulose/resins (16 polyethylene, 17 polypropylene, ..., 29 PET, etc.) shown in the drawing of Fig. 11 were capable of low-temperature soldering with ultrasonic waves. In addition, ultrasonic soldering was possible for 4 cutting boards, 6 cork boards, etc. shown in FIG. 10 described above.

12 shows an experimental example of the absence of ultrasonic output (without preheating) of the present invention.

Figure 12 (a) shows an example of experimental conditions. Here, experiments were conducted under the following experimental conditions.

Iron tip temperature: 180±5℃

·Slide-duck setting value (V): 14

・Sanbonda (trade name of ultrasonic soldering device) Display temperature (℃): 180±5

Material: Poron sponge

12(b) shows an example of an experimental result of ultrasonic output. Here, the items in the horizontal direction respectively represent the following.

·Ultrasonic power (W) represents the ultrasonic power (W) applied to the iron tip.

· Solderability shows workability, solder adhesion, etc.

Adhesion at the time of bending was judged by the degree of peeling when the film was bent.

·Film effect indicates the degree of penetration due to damage when a soldering iron is applied.

Among the above, when the ultrasonic power (W) was changed to 1, 2, 3...10, experiments were conducted on three different items, and the experimental results shown in Fig. 12(b) were obtained.

From these experimental results, it was revealed that good results (ultrasonic soldering results) were obtained for three items at an ultrasonic power of about 7 W or more (preferably about 10 W).

Fig. 13 shows an example of a temperature cycle test of the low-temperature solder of the present invention. This represents an intermediate result at 337.8H of the temperature cycle test. At the time of this intermediate result, no change was recognized in the adhesiveness at the time of the start of the experiment and the time of the intermediate result in both ultrasonic soldering and soldering without ultrasonic waves.

1: Solder material
2: Solder material input dish
3: melting furnace
4: heater
11: Substrate (e.g. PET plate 0.1mmt)
12: aluminum film (foil)
13, 13-1: ultrasonic soldering iron tip
14: low temperature solder
15: ribbon or wire with low temperature solder

Claims (20)

In low-temperature soldering composed of Sn, Bi, or In, or an alloy of Bi and In,
A main material composed of at least one of Al, P, Sb, and In (except for the case where In is contained in the base material) in a base material that is Sn, Bi, or In, or an alloy of Bi and In. ) in a total maximum of 3 wt% or less, preferably 1.0 wt% to 1.5 wt% or less, and 0.01 wt% or more are mixed and melted and alloyed to enhance adhesion. characterized by
low temperature solder. According to claim 1,
The melting temperature of the low-temperature solder after melting and alloying is equal to or lower than the melting temperature of the base material.
low temperature solder. According to any one of claims 1 to 2,
Characterized in that an auxiliary material made of an alloy containing at least one of Al, P, Sb, and In is incorporated into the base material as necessary to melt and alloy it.
low temperature solder. According to claim 3,
Characterized in that the alloy of the sub-material is an alloy of Cu and P
low temperature solder. According to any one of claims 1 to 4,
Into the base material, Al, CuP, and, if necessary, In as the main material, in a total maximum of 3 wt% or less, preferably 1.0 wt% to 1.5 wt% or less, 0.1 wt% or more are mixed and melted and alloyed.
low temperature solder. According to any one of claims 1 to 5,
Characterized in that the base material, the main material, and the sub-material are divided into batches or a plurality and mixed and melted and alloyed.
low temperature solder. According to any one of claims 1 to 6,
Characterized in that it is used for soldering lead wires to electrodes of solar cell substrates and liquid crystal substrates
low temperature solder. According to claim 1,
As a product in which adhesion is enhanced by melting and alloying, alloying is performed for metals to be soldered, sintering is performed for inorganic materials formed by firing oxides, and With respect to cellulose/resin materials, it is characterized in that one or more of the adhesive forces to be solidified by entering into gaps between irregularities on the surface and to be fixed are enhanced.
low temperature solder. According to claim 8,
The metal is at least aluminum, copper, iron, stainless, or silicon, the inorganic material is at least glass or ceramic, and the cellulose/resin is at least paper, wood, resin film, resin fiber, or carbon fiber. doing
low temperature solder. According to any one of claims 8 to 9,
10 each from 139 ° C for melting at least in the Sn-Bi alloy, 120 ° C for melting at least in the Sn-In alloy, and 90 ° C for melting in the Sn-In-Bi alloy. Characterized in that the adhesion is enhanced by soldering at a high temperature of ℃ or higher
low temperature solder. According to any one of claims 8 to 10
Low-temperature solder, characterized in that the soldering is ultrasonic soldering. According to claims 1 to 7,
Characterized in that low-temperature solder is melt-coated on the surface of a wire rod or ribbon
Low-temperature solder coated lead wire. According to claim 12,
The melt coating is characterized in that the melt coating in the state of applying ultrasonic waves
Low-temperature solder coated lead wire. In the manufacturing method of low-temperature solder made of Sn, Bi, or In, or an alloy of Bi and In,
A main material consisting of one or more of Al, P, Sb, and In (except for the case where In is contained in the base material) is added to a base material that is Sn, Bi, or In, or an alloy of Bi and In, in a total maximum of 3 wt% Below, preferably 1.0wt% to 1.5wt% or less, a step of mixing 0.01wt% or more,
The step of melting and alloying the mixed material
equipped,
characterized by enhancing adhesion
Manufacturing method of low-temperature solder. According to claim 14,
The melting temperature of the low-temperature solder after melting and alloying is equal to or lower than the melting temperature of the base material.
Manufacturing method of low-temperature solder. The method of any one of claims 14 to 15,
Characterized in that a sub-material made of an alloy containing at least one of Al, P, Sb, and In is incorporated into the base material as necessary to melt and alloy it.
Manufacturing method of low-temperature solder. According to claim 16,
Characterized in that the alloy of the member is made of an alloy of Cu and P
Manufacturing method of low-temperature solder. The method of any one of claims 14 to 17,
Into the base material, Al, CuP, and, if necessary, In as the main material, in a total maximum of 3 wt% or less, preferably 1.0 wt% to 1.5 wt% or less, 0.1 wt% or more are mixed and melted and alloyed.
Manufacturing method of low-temperature solder. According to any one of claims 10 to 14,
Characterized in that the base material, the main material, and the sub-material are divided into batches or a plurality and mixed and melted and alloyed.
Manufacturing method of low-temperature solder. According to any one of claims 14 to 18,
Characterized in that it is used for soldering lead wires to electrodes of solar cell substrates and liquid crystal substrates
Manufacturing method of low-temperature solder.

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