TW200408727A - Surface treating agent and surface treating method for tin alloy - Google Patents

Abstract

The present invention provides a surface treating agent for improving the solder wettability and anti-oxidation ability of tin alloy. Furthermore, the present invention also provides a surface treating agent, which enables a solder paste with high storage stability, and a tin alloy in which the whisker formation being inhibited. Said surface treating agent is characterized in comprising acid phosphate ester, and/or its salt, and is useful for treating tin alloy, the said acid phosphate ester containing one or two saturated or unsaturated alkyl group. The present invention provides a method using said surface treating agent for treating tin alloy. The preferred tin alloy is the solder alloy containing any one or two or more metal of Zn, Bi, Cu, Ag, Sb in Sn.

Description

200408727 Description of the invention [Technical field to which the invention belongs] The present invention relates to a surface treatment agent for a tin alloy and a surface treatment method using the same. [Previous technology] Less than the connection technology, a material with a lower melting point is used to join objects. It is widely used in the modern industry to join and assemble electronic equipment. Generally, the solder used is Sn_Pb alloy, because its eutectic composition (63% Sn_remaining pb) has a melting point that is lower than 183t, so soldering is performed to 23 (TC, almost no heat is caused by electronic parts and substrates) In addition, the Sn_Pb alloy not only has good weldability, but also solidifies immediately during welding. It has the superior feature that it is difficult to cause cracking or peeling even if vibration is added to the welded part. Synthetic resins such as substrates and substrates, and metals such as conductor frames, are buried under the ground without being incinerated when discarded. In recent years, the rainfall on the ground has shown acidic inclination (acid rain), buried under the ground The solder of electronic equipment will dissolve, which will cause the problem of contamination of groundwater. For this reason, especially in the electronic equipment industry, the process of replacing lead-free solder (lead-free lead) is rapidly progressing. In addition, On the external wire terminals, in order to improve the #wetability and softness, 'the main implementation of the material is (9Q% Sn_except for the rest:' For this reason, it is also expected to move towards non-pure development. No material ore cover ^ Adopt Alloy 's can be broadly divided into]] _ Ag (Cu), Department,

Sn-B] · Departments, each with its own advantages and disadvantages are called Ding and Wen Que. It is known that they have not yet reached the point where they can completely replace s „_Pb 3150] 〇 200408727 alloy.

Sn-Zn series alloys have the advantage that the melting point is closer to that of the conventional Sn_pb series alloys, so there is no need to change the existing equipment and procedures. In addition, the mineral film has superior mechanical strength and low cost. However, because Zll is an active metal, it is relatively easy to oxidize, and because the solder wettability of Zn_Sn-based alloys is very poor, it is currently considered to be the least practical. Soldering is used to mount electronic components on the upper surface of the substrate. The amount of soldering has increased in recent years. Generally, solder paste is mainly composed of solder alloy powder, and a flux containing a binder, an active agent, a thixotropic agent, a surfactant, and a solvent is added. Although lead-free solder paste is discussed for Sn_Ag (Cu) -based alloys, Snjn-based alloys, and Sn_Bi-based alloys, the sn_h-based A is all the same as described above because it is closer to the eutectic temperature of the conventional Sn_pb-based tan materials, so it is considered to be the most With alternative candidate potential. But as mentioned above, because. Comparator 2 is emulsified, so the solder paste using Sn_Znf 'alloy as the solder powder is significantly suboxidized with the activator contained in the flux, and the storage stability is significantly submerged. However, the disadvantage of H Yan is due to JP ¥. In addition, there is a need for 0 friends. Non-reactive gas generally has many proposals to prevent solder network φ $ & For example, in Japanese Patent Document I, it is revealed that on the surface of the powder: coatings based on base ether phosphate, polypropylene, etc. * Emulsified ethyl ether, alkyl ether-based non-ionic surfactants, coatings such as metal salts, etc. To prevent oxidation. In addition, it is disclosed in the patent that polyoxygen is used to prevent oxidation of the obtained solder paste by combining the solder powder with the ethylene oxide-containing alkyl ether phosphoric acid N r 0 xy ethy] ejle. d 卞 315010 6 200408727 Ball Grid Array (, _U Gl: id Array, BGA) is an external terminal used by solder balls. Sub-configuration of the main_dimension surface-mount package 'B in the middle = ball' For example, in order to prevent the contact between electronic components and the substrate I, a proposal has revealed that the solder ball is applied to the elastic member to implement the Sn clock (Patent (Patent Document 1) said that the book is not profitable 4 inches open 2001- Japanese Patent Publication No. 294901 (Patent Document 2) Japanese Patent Special Deduction 4 inch opening 2000-271 Japanese Patent Publication No. 781 (Patent Document 3) Japanese Patent winning n Japanese Patent Publication No. 1 1-284029 [Content of the Invention] ^ Yes Due to the above facts, the solder wettability and oxygen resistance of the too A dq alloy are as follows: the second is to provide-a kind of surface treatment agent that clarifies the purpose of Sn. The occurrence of this ~ ~ alloy recording Surface treatment agent. The inventors said that the present inventors have targeted Sjl Yaken, and found that the treatment agent that contains and inhibits the oxidation of the W surface is used to deeply iron the acidic phosphate ester, and the surface of the base 11 is not modified. $ 纟 予 oxidation resistance, and improve solder adhesion, .Q.,., In addition, it was found that the storage stability of ^ ^ ^ a, 含有 containing Sn alloy powder subjected to the surface treatment was significantly improved. Moreover, the 经 i, l -k ^ Jka a ^ treatment The Sn alloy plating was confirmed to significantly suppress the occurrence of crystals. That is, the present invention is as follows: (]) A surface treatment agent for Sn alloy Yumoto ^ " containing and] or 2 saturated or not "Saturated alkyl acids" are self-initiating phosphates and / or linoleum. (2) The surface treatment agent of Bali is as described in the above (1), wherein the above-mentioned Sn alloy 3150J0 7 200408727 is Sn contains one or both of ~,, ~, or one of the solder alloys. (3) The surface treatment as described in the general description (2), wherein the upper alloy is a Sn-Zn alloy. ⑷- A surface treatment method for an Sn alloy, using the surface treatment agent described in any one of the above items ⑴. ^ An electronic component or substrate, which is obtained by applying a Sn alloy ore coating to the surface of the right terminal of the connecting terminal of the electronic component or substrate. , And then use the surface treatment method described above to perform surface treatment =: Sn alloy balls are those that have been subjected to surface treatment by the surface treatment method described in the above paragraph. One of the BGA (ball grid array) packages uses the above-mentioned Sn alloy balls as electrical connection components. (8) Structural products are those in which the Sn alloy solder balls as described in (6) above are arranged, and connected to a circuit board. Two types of Sn alloy solder powders are prepared by surface treatment by the surface treatment method described in (4) above. By. ⑽A solder paste 'uses the Sn alloy solder powder described in ⑼) 构) above-mentioned components, and uses the embodiment described in (10) above. [Embodiment] Dry Q. The Sn alloy used in the present invention is best viewed from the perspective of environmental pollution and other issues. It is preferably Q person without a buckle / v,]

Cu, In, and A include, for example, solder alloys in which any one or more of Zn, Bi, and δb are included in ~. In addition, 315010 8 200408727

The Sn-Zn alloy is preferably used because its melting point is close to the conventional Sn_Pb alloy. The acidic phosphate ester having one or two saturated or unsaturated alkyl groups used in the present invention is one shown in the following general formula (丨). In general formula (1), R1, R2, and R3 are saturated or unsaturated. A saturated alkyl group or hydrogen, and any one of R], R2, and R3 is a saturated or unsaturated alkyl group or hydrogen. o = p

OR2

Tetraene The aforementioned saturated or unsaturated alkyl group is preferably a saturated or unsaturated alkyl group having 10 to 26 carbon atoms, and particularly preferably a saturated or unsaturated alkyl group having 12 to 24 carbon atoms. Acid phosphates with one or two saturated or unsaturated alkyl groups, such as: acid dodecanoate, bis (dodecane) phosphate, acid tetradecane, and acid di ( Fourteen burns) Cool, Filled acid monohexadecyl ester, Filled acid dihexadecyl ester, Broken acid monooctadecyl ester, Filled acid di (eighteen burner) Cool, Lepicric acid monoicosyl ester, Di (icosane) phosphate, mono-dialkyl phosphate, bis- (di-alkyl) phosphate, mono-tetra-alkyl phosphate, bis- (tetra-alkyl) phosphate, di-dodecyl phosphate, di (ten) phosphate Diene) Cool, Monodecyl Phosphate, Monohexadecyl Phosphate, Di (Decyl Ester, Di (octadecene) Phosphate, Si Monophosphate, Mono-Phenadiene Phosphate, Di (Phenyl Phosphate) Esters, bis (tetraene) phosphates, etc.). One (or two) acid phosphates with less end groups are saturated (or unsaturated) 315200] 408200727 The salt system only belongs to the above one (or two) ) It is sufficient to have a saturated (or unsaturated) alkyl 2 I 11 phosphate and a salt dissolved in water as a basic substance, preferably an amine salt. Furthermore, it has one or two salts. Saturated or unsaturated alkyl acid phosphoric acid ^ In the manufacture, when a mixture of acidic phosphorous esters with one saturated or unsaturated alkyl ester and acid phosphates with two saturated or unsaturated alkyl esters is obtained, it is not necessary to cut The mixture can be used directly. In addition, the acid phosphate mixture can also contain a small amount of phosphate triester. The surface treatment agent of the present invention can be an acid phosphate having one or two saturated or unsaturated alkyl groups, and / Or its salt is used by dissolving in a solvent, and the d 'used is only required to be soluble, and is not particularly limited, but from the viewpoints of solubility, easy drying, cost, etc., isopropyl alcohol, Solvents having a hydroxyl group such as lysin, hydrocarbons such as toluene or n-hexane, or ketones such as propane, etc. Furthermore, the "surface treating agent of the present invention may be contained without impairing the purpose of imparting desired properties". And the amount of additives within the range of the original properties. The additives may include, for example, preservatives, surfactants, etc. The surface treatment of the Sn alloy using the surface treatment agent of the present invention /, a method for forming a coating on the surface of the Sn alloy Yes, the method of immersing Sn alloy in # 1 3 such as only-again / shell side, surface treatment agent, or spraying the surface agent> Li or air, ... tender, doctor blade coating machine, type coating machine , Gravure coater, reverse coater, liquid-injection coater, and other methods of coating. The method of drying the village cloth is, for example, using hot air drying and newspaper type] 〇3] 5〇] 〇2UU4U « / 2 / d'Infrared drying, far-infrared drying, and other methods can be used alone or in combination of two or more types. In other words, there is no special thickness of 6mm. From the viewpoint of cost, it is rolled. The shape of the surface treated by the surface treatment agent can be any shape such as linear, plate, tape. 笮 μ paste ”u Mengzhi / flake, granular (Sn solder ball), powder (n bad powder), etc. The Sn 5 gold powder is treated with the surface treatment agent of the present invention, and a soldering aid containing a binder, an active agent, a deflection agent, a surfactant, and a solvent can also be added to the Sn 5 gold powder for use as a solder paste. The above-mentioned adhesives, active agents, thixotropic agents, and surfactants can be used as known. Embodiments Hereinafter, embodiments of the present invention will be described. < Example 1 > In yoke example 1, the solder wettability of the Sn-Zn alloy plated surface treated with the surface treatment agent of the present invention was significantly higher than that of the surface treated without the surface treatment. Improved results. 1 to 4 kinds of} wt% isopropanol solutions with a saturated or unsaturated alkyl acid 4 Ijl 酕 as an active ingredient are prepared in the following Table 丨. In addition, the above-mentioned acidic phosphate-based monomers or dimers are approximately equimolar compounds. Furthermore, the scale bronze hoop material (18x100mm) was subjected to the following treatment. Alkaline electrolytic degreasing (room temperature, 5A / dm2, treatment at about 30 seconds) —Water leeches—Acid stains (10% sulfuric acid, room temperature, 5 seconds) —Washing—Chemical polishing π 315010 200408727 (CPB-40, room temperature Immersion for 1 minute and water leaching ^ acid leaching (10% sulfuric acid, normal temperature, 5 seconds) —water-washing is performed on this substrate with a film thickness of about 5 μηι for 811_211 minutes (bell bath: sn_ 10zn (zn content rate 10%), Electric clock conditions: cathode current density 3A / dm2, temperature 35 ° C, pH 4.0, liquid flow, and cathode shake plating). This Sn-Zn-plated substrate (hereinafter referred to as "sn_zn substrate") was used in Immerse in the isopropyl alcohol solution of the above-mentioned saturated or unsaturated sulphuric acidic phosphoric acid for 1 minute. Then, use a dryer to dry and use it as a test substrate, and perform the following solder wettability evaluation test. After the surface treatment agent of the present invention is subjected to surface treatment (immediately after post-treatment) and PCT treatment (placed in a closed steel at a temperature of 105 ° C and a humidity of 100% for 16 hours), the menisc method (menisc) is used. 〇graph method) evaluation and lead-free solder (tin: silver: copper = 96 5: 3: 〇5, Temperature 245 ^). In addition, the 'welding aid system uses Cai 2 00 (Durham Chemical Research (company name' transliteration)). The test results are shown in Table q. In addition, the comparative example is a Those who did not apply a surface treatment to the above Sn_Zn substrate were used as test substrates, and the results of the same evaluation are shown in Table 丨. 315010 12 200408727 Table

〇 = 〇 seconds or more, less than 3 seconds, χ = 5 seconds * = Comparative Example It can be judged that the surface treatment method of the present invention has significant improvement in solder wettability to the Sn-Zn alloy. Other "alloys also have improved solder wettability < Example 2 >" In Example 2, the Sn-Zn alloy was plated and applied | The surface treatment was performed after the two old whiskers were produced.丄 々 々 phenomenon, compared to the suppression effect is not implemented. t main test, the silk clerk will not clearly show that the treatment will be implemented as in Example 丨 4 kinds, and not implemented > ϋ η & gold plating base The substrates that have not been processed are left for 24 hours in a temperature but humidity environment with a temperature value of 315030 33 200408727. After the substrates are sufficiently dried, the scanning electron microscope (S) EM, scanning eiectr0m1Cr is used. 〇scope) surface observation, as a result, a lot of crystals were observed in those who had not been subjected to the surface treatment. In contrast, those who had undergone the surface treatment had no whiskers at all regardless of their active ingredients. ≪ Example 3 > The result of improving the solder wettability of the f solder paste in Example 3. The results of using the surface-treated Sn-Zn alloy powder as compared to those who did not perform the surface treatment showed that a Mingshi same household was used. 1 'Modulation! 4 types with saturation or desaturation The acidic phosphoric acid of alkyl is an effective ingredient! After wt% isopropyl alcohol solution, hUBi is finally crushed in this cold liquid for i minutes, then filtered through a glass filter and dried. This surface is treated with low degree丨 | μ of 枓 枓, and welding aids (rosin 60wt% / 0, butylcarbitol 30wt%, know #i 余 占, a wind castor oil 9wt%), according to weight ratio 9: 1 Thoroughly mix to form a solder paste. This customer flat; g is coated on a copper plate with a 7mm 0 / lmmt cylindrical shape using a jig.. Place this copper plate on a hot plate set to 230 ° C. Add it, it takes 1 () seconds since the fire-dried T begins to melt ... Λ ± Φ 'ft-,… Remove the copper plate. The heating system is ordered in the chaos. After the welding solidification date…, refers to shooting and measuring the welding thickness The upper and upper wet diffusion areas. The test results are shown in Table 2. In addition, the bad samples were made in the comparative example except that the acoustic surface treatment was not performed, and the solder paste was made in the same way as in the third example. One is not in Table 2. 3150) 0 \ 4 200408727 Table 2 Number of active ingredient diffusion area (mm2) 1 Monophosphate / di (dodecane) purpose 72 2 Acid mono / di (tetradecane) vinegar 74 3 Monolithic acid mono / di (hexadecane) vinegar 73 4 Mono / di (octadecane) phosphate 76 5 Mono / di (icosane) phosphate 78 6 Mono / di (phosphoryl dioxane) vinegar 77 7 Mono / di (phosphoryl dioxane) vinegar 77 8 Limonic acid mono / di (dilute) distillate 75 9 Limonic acid mono / di (dilute 14) ) Purpose 78 10 Carboxylic acid mono / di (hexadecene) 77 77 Phosphate mono / di (octadecene) 76 76 12 / Bis (fluorenediene) purpose 78 14 Mono / bis (fluorene-tetra dilute) ester of carnic acid 79 151 Untreated 40) 5 335010 1 Comparative Example < Example 4 > In Example 4, a surface-treated surface was used. The storage stability of the treated Sn-Zn alloy powder solder paste showed significantly improved results compared to those without surface treatment. The solder paste shown in Example 3 was stored frozen at 5 ° C, and the storage stability was evaluated. Table 3 shows the period during which the wet spread area of the solder paste is less than half of the initial period. 200408727

Table Number Active Ingredients _ ^ 1 Monophosphate / di (dodecane) citrate 2 Dipic acid mono / di (tetradecyl) Pyridium 3 Monophosphate / di (hexadecane) phosphate 4 Monophosphate / di (ten) Octane) SI 5 Phosphate mono / di (icosane) _ 6 Phosphate mono / di (dioxane) _ -J or more 7 Phosphate mono / di (tetrateane) g Purpose 3 3 8 Phosphate mono / di ( Dodecene) Sterilization—3 or more 9 Carboxylic acid mono / di (tetradecene) S for more than 3 months 10 Mono / di (hexadecene) phosphate 3 11 Mono / di (octadecene) phosphate Esters 3 months or more 12 Mono / di (icosene) phosphates More than 3 months 13 Mono / bis (pinediene) phosphates 3 months or more 14 Mono / bis (tetraene) phosphates 3 More than 15 months * Untreated 1 month Comparative Example Industrially available 'According to the present invention, the use contains one or two remaining and remaining

A surface treatment agent for the acidic linoleic acid § and / or its salt, and a surface treatment agent for ^ τ M alloy, which can impart oxidation resistance and improve solder wettability. Furthermore, the surface treatment agent of the present invention The treated solder paste containing Sn alloy powder will greatly improve the storage stability. The Sn alloy plating after this surface treatment can greatly suppress the occurrence of whiskers. 16 315〇] 〇

Claims (1)

Also, the scope of patent application: a kind of surface treatment agent for tin alloys, straight acidic phosphoric acid and / or salts thereof, which are saturated or unsaturated based on Af characteristics. • If the scope of patent application is 坌 All-in-one member of the surface treatment agent, among the above-mentioned tin-manganese series tin containing Zn, Bi, Cu, Ag, s solder alloy. One or more of the above: • As the surface treatment agent of the second patent application in the patent application, among them, the above 3 Meng series Sn-Zn series alloy. .Surface treatment method of tin alloy, etched field from ^ Zhouzhou to any of the 3 items _ ^^ ^ Use of the surface treatment agent in the scope of patent application No. 1,1. Sub = substrate is a person who has performed surface treatment on the surface of the connection part of the electronic component or the substrate in item 4 without gold plating, and then applies the surface treatment method of the patent application 6. tin. Jin Qiuqiu is the one who applied the surface treatment in the 4th patent application; ^ $ 考 Method. Surface treatment of the 4 items of dry siege. The ball grid array package uses gold solder balls as thunder gas, pot pull ^ Concentrate on the tin of the 6 sieges, "" users of milk connection components. The spleen is placed on the electronic parts by two main strikes: the tin alloy solder ball with the range of the 6th item is 9-^. And it is connected to the circuit board. • A kind of tin δ gold solder powder, which has been treated on the surface. The surface of the item. 10. A kind of solder paste, which is used by Shinsaki. The tin alloy solder powder U of the patent No. 9 of the monthly patent. 3] 5〇] 〇17 200408727 柒. Designated representative map: No plan in this case (I) The designated representative map in this case is: (). (II) The component representative of this representative map Simple explanation of symbols: 捌. If there is a chemical formula in this case, please disclose the chemical formula that best shows the characteristics of the invention ... OR1 0 = P—OR OR 2 3 315010