TW200908392A - Electrically conductive die bonding agent for LED - Google Patents

Abstract

This invention provides an electrically conductive die bonding agent for LEDs, the electrically conductive die bonding agent exhibits an excellent reliability on connection and an optical stability (stable reflection index). The electrically conductive die bonding agent contains: (A) an alicyclic epoxly resin containing an average of 0. 5 or more of hydroxide group per molecule, (B) a non aromatic, blocked poly isocyanate, and (C) an electrically conductive filler.

Description

200908392 IX. OBJECTS OF THE INVENTION: The present invention relates to a conductive die attaching agent for LEDs for bonding a light emitting diode (LED) wafer to a substrate or the like, and An LED obtained by using the LED material (4) agent. [Prior Art] LED has long life, low power consumption, low heat generation, high speed responsiveness, right! The characteristics of environmental impact, small size, etc., are applied to various fields such as liquid crystal display, light signal, illumination, and display devices. b d. ^ In the law, the method of using the die attach _ ring to slap the LED chip on the WP, lead frame, substrate, etc. From the point of view of the south elastic rate of the Pan Guyan I. On the agent - #是# From the point of view of the two, this grain is viscous oxygen resin or aging slag varnish phenol nov〇iac When the type is used, the resin in the county will absorb the LEDs; the color is the same as the light and the material, and the height is degraded when the coffee is long. In the case of the lamp, there will be a macro/by θ h in order to cope with the 4 problems, but when an argon-type epoxy tree is added as an acid anhydride hardener as a hardener (see;, Guang:: Xuan (―会_ Not only does it have problems in terms of workability: the effect of improving the safety of the period is also a problem. Another resin (see Patent Document 2), but the second one has the use of poly-wei, and the strength of the acquisition is weak. It is difficult to ensure the reliability of the special 320307 5 200908392. So now we are expecting led good. 'From the point of view of connection reliability and light stability, the use of conductive die attach adhesives can be more advanced. [Patent Document 1] JP-A-2003-26763 [Patent Document 2] pp. Unexamined-Japanese-Patent No. 7-25987 (Summary of the Invention) The object of the present invention is to provide a conductive grain adhesion I for LEDs. The conductive die attach adhesive for the LED can provide a LED with excellent connection reliability. A woman (method of solving the problem) The inventor has continuously studied carefully to achieve the above object, and the result is that the LED is electrically conductive with a specific composition. Amorphous die attach adhesive can be achieved Therefore, the invention is completed. That is, the invention relates to a kind of LED material electric grain adhesive, two = 丨), each of which contains an average of 〇, more than 5 kinds of alicyclic latex U-day (8) a non-four fragrant polyisocyanate § blocking compound (10) such as H 〇 cylnate), and (c) a conductive filler, and in addition to the use of the day granule adhesive to obtain the led. (Effects) By using the conductive die attach adhesive for LEDs of the present invention and using the = wafer (four) on an interposer, a lead frame, a substrate, or the like, it is possible to provide a LED excellent in connection reliability and light stability. Application method] 320307 6 200908392 The invention relates to the (4) branch of the present invention, which comprises: L) a mother-molecule containing an average of 0.5 or more-based alicyclic gas trees (8) a non-aromatic non-polyisocyanuric acid blocking compound. And (c) a conductive filler. (A) The component is an alicyclic epoxy resin having 0.5 or more hydroxyl groups per molecule + containing a preferred cross-linking yield. At the same time, it can be used as a household. In addition, the ice and hydroxyl groups are averaged from 0.5 to (A). 2 or more. & When using a plurality of waxy ring-shaped epoxy waxes, although the above, as a whole, it is preferable to prepare one of eight τ ^ 3 3 hydroxy groups preferably per molecule - two: The knife contains an average of more than 5 interesting bases, and the sub-thousands contain 〇.5 to one of the hydroxyl groups. The alicyclic epoxy resin is a resin and hydrogenated double. The bisphenol-incorporated epoxy chlorine is added. _ varnish type epoxy two = 曰: 虱 biphenyl type epoxy tree gambling, plus chlorinated epoxy resin 3? Erli saki lacquer type epoxy resin has been burned a few vinegar, 2 Μ 己 基 基Base 3,4,4,-epoxycyclohexylmethyl)hexylenylcyclohexene, bis (3,4.epoxycycloaliphatic hydrocarbon, etc., ring-to-ethyl group _3,4· county base ring Epoxy resin such as hexane or the like: fat and the like. In the case of (4), each of the eight, and one of the three soils is used together. As described above, the whole molecule has an average of i ο containing more than 5 ketone groups, preferably 0.5 to 6 per gram. Hydroxyl.隹: For the component (4), the argon-type epoxy tree wax shown in the following formula is 320307 7 200908392

(wherein, X is -CH2-, -C(CH3)2- or direct bonding; 111 is on average 0.5 or more, preferably 〇.5 to 6). Among these, from the viewpoint of storage stability, an epoxy resin of a hydrogenated bisphenol A type or a hydrogenated bisphenol F type is used in the present invention by using the non-fragrance of the component (B). The blocking compound of the polyisocyanate as a hardener can suppress the decrease in the reflectance of the hardened crystal grain adhesive and contribute to light stability. In addition, since the amine vinegar bond ((10)thane b〇nd) is generated by hardening, strong bonding strength can be maintained at a high temperature, resulting in an increase in connection reliability. The component (B) and f may, for example, be an aliphatic polyisotope such as hexamethylene diisocyanate, diisocyanate, or trimethylhexamethylene diisocyanate. A waxy cyclic polyisocyanate such as cyanic acid vinegar or isophorone diisocyanate: a phenolic compound (for example, phenol, cresol, phenol, butanol, etc.) or an indoleamine compound (for example, hexamidine) Amines such as valeramine, butylamine, etc., and oxime compounds (such as aldoxime (Amp), keoxime (acetone) Jiang, methyl ethyl ketone jiang, cyclohexanone, etc.), malonic acid diacetate, b-bundle = acetaminophen, acetamidine acetone and other blocking agents (10) can be closed by the state = from light stability From the point of view of the nature, the viewpoint of the light stability of the _ 细 细 芳 四 四 四 化合物 化合物 化合物 化合物 化合物 化合物 化合物 化合物 化合物 化合物 脂肪 脂肪 脂肪 脂肪 脂肪 脂肪 脂肪 脂肪 脂肪 脂肪 脂肪 脂肪 脂肪 脂肪The oxime compound or the indoleamine 320307 8 200908392 In addition, the blocking compound obtained by blocking the component (B) may be used singly or in combination of two or more. The bismuth-and-conductive filler is not particularly limited, and examples thereof include metal fine powders such as silver, gold, steel, and alloys, and inorganic or organic fillers coated with gold, silver, and palladium. The shape of the palladium is not particularly limited, and may be, for example, a spherical shape or a scaly shape. The scale is preferably a sheet, and the average particle diameter may be, for example, 5 to 15 mm. (6) The ingredients are used alone or in combination of two or more. In the present invention, the component (A) is preferably 2 to 15 parts by weight, more preferably 3 to 13 parts by weight, based on 100 parts by weight of the total of the components (8), (8) and (C). (8) The composition is preferably! It is preferably 2 to 8 parts by weight to u parts by weight. The component (C) is preferably from 74 to 97 parts by weight, more preferably from 79 to % by weight. From the viewpoint of reactivity, the die attach adhesive of the present invention preferably contains a hardening catalyst. The hardening catalyst may, for example, be (D) an aluminum chelate compound. (D) The aluminum chelate compound is not particularly limited, and examples thereof include a compound obtained by disposing an anion with three cold-ketoenolates in an anion. It can be used as aluminum ethyl acetoacetate diisopr〇pylate, aluminum triacetate, ethyl diacetate diisoxyl aluminum, bis(acetic acid ethyl acetate) Ethyl acetonate aluminum, or bis(acetonitrile)aluminum, or acetonitrile acetate diisopropoxide aluminum is used. Among them, from the viewpoint of the pot life, it is preferred to be a base (equivalent to the following formula: 〇 is C1SH37 of acetonitrile acetate diisopropoxy aluminum (octadec-9-alkenyl-ethene) Acetate-0^,03) dipropen-2-anoyl aluminum: 320307 200908392 H7C-〇n

H, C, /°, c3h7

OR The '(9) component may be used singly or in combination of two or more. The total of 100 parts by weight of the components of r=:, (B) and (C), and (9) preferably 0.05 to L1 parts by weight, more preferably 〇 to 7 parts by weight. Further, in view of k-bonding property, the die attaching agent of the present invention preferably contains a coupling agent. The coupling agent may, for example, be a (8) decane coupling agent. (8) Shi Xi siu coupling _ is not particularly limited, and examples thereof include a vinyl-containing stone m (3,4· ring) such as vinyl chlorochloride, ethylene trimethoxy (tetra), vinyl triethoxylate or the like. Oxycyclohexyl)ethyltrimethoxy, 3_glycidoxypropyltrimethoxy, 3·glycidoxypropylmethyldiethoxylated 3-epoxypropoxy a styrene-containing decane, such as propyldiethoxy oxalate or the like; a p-styryl trimethoxy group (tetra) or the like; a styryl-containing decane; a 3-methylpropenyloxypropyl group; Methyldimethoxydecane, 3-methacryloxypropyltrimethoxydecane, 3-methylpropenyloxydiylmethyldiethoxydecane, 3-mercaptopropenyloxypropane The base of triethoxy decane special 3 has a gas base based on Shi Xizhuo; 3 · (meth) propyl welding azeoxypropyl tridecyloxy decane and the like (fluorenyl) propylene sulfhydryl decane; N-2 -(Aminoethyl)_3-aminopropylmethyldimethoxydecane, N_2-(aminoethyl)_3•aminopropyltrimethoxydecane, N-2-(aminoethyl) · 3-Aminopropyltriethoxydecane, 3-aminopropyltrimethoxy Baseline, 3-aminopropyltriethoxydecane, 3-3-triethoxydecyl-N-(l,3-dimethyl-butylene)propylamine, oxime-phenyl_3_ 320307 10 200908392 An amine-based zebra or the like containing amino group, such as aminopropyltrimethoxy sulphate. From the viewpoint of lightness, it is preferred that it does not contain an aromatic ring, and = cyclyl) ethyltrimethoxydecane, 3-glycidoxypropyldimethyl decyl decane, 3-epoxy Propyloxypropylmethyldiethoxymei 3-glycidoxypropyltriethoxydecane or the like contains an epoxy two group: hydrazine: may be suitable. Further, the component (8) may be used singly or in combination. The component (6) is preferably from 0.1 to 11 parts by weight, more preferably from 5 to 95 parts by weight, based on 1 part by weight of the total of the components (A), (8) and (C). The present invention may contain a viscosity modifier, an antifoaming agent, a flame retardant, an ultraviolet absorber, an antioxidant, a solvent or the like as an optional component insofar as the effects of the present invention are not impaired. The conductive die attaching agent for LED of the present invention is prepared by mixing and mixing (9) and (8) as needed. The conductive grain adhesive for LED of the present invention can be applied to an interposer, a lead frame, a substrate, or the like, and after the L £ D wafer is disposed on the coated portion, it can be 1 to 3 hours at 140 to mt (for example, (9) to 17th generation to jade to 2 hours), the die attach adhesive is heat-hardened to form led. (10) Wafer system Any of a blue coffee wafer and a white LED wafer can be used. According to the present invention, a coffee conductive grain adhesive excellent in light stability can be obtained. The light stability can be evaluated by measuring the reflectance of the grain adhesive after hardening, and the change in reflectance is small and the stabilizer can be regarded as excellent in light stability. Specifically, the die attach adhesive of the present invention is applied to a glass substrate at a thickness of 150 "m, and then heat-hardened for 2 hours, 320307 11 200908392 and then cooled to room temperature to obtain a coating film. The reflectance Xa at 450 nm in the initial stage of the film and the 450 nm of the coating film after the light is irradiated for 1000 hours at a distance of 50 mm from a distance of 50 mm using a blue high-intensity discharge (HID) lamp (400 W, 8000 Lm, 20000 Lx) for the coating film. The reflectance Xb can satisfy Xb/Xa2 0.75. Further, in the present specification, the reflectance is a value measured from an incident angle of 45 degrees from the back side of the glass substrate. (Examples) The present invention is illustrated by the examples, but the present invention is not limited by the examples. In addition, in the following examples, "parts" and "%" mean "parts by weight" and "% by weight" unless otherwise specified. Each of the components was mixed in the blending composition shown in Table 1, and the conductive die attaching agents for the LEDs of the examples and the comparative examples were prepared. The following tests were carried out for each of the examples and the comparative examples. (1) Reflectance Each agent was applied onto a glass substrate at a thickness of 150 / zm, and heat-cured at 150 ° C for 2 hours, and a sample for reflectance measurement was prepared. For this sample, the reflectance was measured from the back side of the glass substrate at an incident angle of 45 degrees by a color difference meter NF999 machine manufactured by Sakamoto Denshi Kogyo Co., Ltd. Then, using a blue HID lamp (400 W, 8000 Lm, 20000 LX, Fig. 1), the sample is irradiated with light at a distance of 50 mm from about 50 ° C for 50, 100, 400, 1000 hours, and the reflectance after the irradiation is compared with the above. The same method was used for the measurement. The results are shown in Fig. 2. (2) Contact resistance on FR4 substrate with Cu/Ni/Au electrode (Fig. 3-A), 12 320307 200908392 Apply each agent to a thickness of 70 // m to a side length 〇 5 mm square ( Figure 3-B), and a plate made of silver-nickel alloy (iron: nickel = 58: 42) is plated on the coated portion to make the thickness of each agent 50 / / m (Figure 3-C). Second, at 15 baht. (: heat hardening for 2 hours, applying sealant (sealant) (bisphenol F type epoxy resin, alicyclic epoxy resin, methyl nadic anhydride, and mixture of hardening accelerators) reset ratio 17.5 : 32.0 : 50.0 : 0.5), at 18 〇. Heated for 2 hours, cooled to room temperature, and prepared a sample for resistance measurement (Fig. 3_D). Connect the probe to the electrode of this sample and circulate 1 mA. The current was measured, and the resistance value was measured. Then, the sample was placed on a hot plate of 300 t for 15 seconds, and then cooled to room temperature, and the resistance value was measured in the same manner as above. This operation was repeated for 4 samples. 3 times. The results are shown in Fig. 4. In addition to this test, according to the JEDEC level 3 test, the predetermined inhalation reflow is performed by placing the sample for measuring the resistance value at 30 t and the relative humidity of I 7〇% for 10 hours. It was circulated to the 26th generation (4), and the money was cooled to the chamber: the resistance value was measured in the same manner as above. This operation was repeated 3 times for 4 samples. The results are shown in Fig. 5. (3) Shear strength In the silver-plated copper FR4 its cylinder μ ^ ^ m... 4 On the substrate, 'dissolve each agent into a square with a thickness of 125// = 2 sides, and place the side of the stone on the coated part, iA ^ at the time of the second, at 150 〇 Heat hardening 2 is less than VP i temperature 'Preparation of shear strength

At room temperature and warfare from the horizontal 胄 I I I 片 , , , , , 307 307 307 307 307 307 307 307 307 307 307 307 307 307 307 307 307 307 307 307 307 307 307 307 307 The results are shown in Figure 7. On the glass substrate, each agent was applied to a square having a side length of 1 mm at a thickness of 50 μm, and a square wafer having a side length of 1 mm was placed on the coated portion, and secondly, heated at 150 ° C. After hardening for 2 hours, it was cooled to room temperature, and a sample for shear strength measurement was prepared. For this sample, the shear strength was measured at room temperature in the same manner as described above. Then, for the sample, the shear intensity after the irradiation was measured by using a blue HID lamp (400 W, 8000 Lm, 20000 LX, Fig. 1) from 50 mm to 150 ° C for 50, 100, 400, and 1000 hours. The results are shown in Fig. 8. (4) Pot life: Each of the agents was placed at 25 ° C and a relative humidity of 50%, and was measured at 25 ° C and 2.5 rpm using an E-type viscometer (machine name TVE-22) manufactured by T0KIMEC. Viscosity. The results are shown in Figure 9. 14 320307 200908392 [Table 1] Resin Hardener Hardening accelerator

Hydrogenated bisphenol A type epoxy resin 氺1 hydrogenated bisphenol A type epoxy resin

氺A Hydrogenated bisphenol A type epoxy resin*2 Cyclohexenyl group, ketone-3', 4'-epoxy ring dilute carboxylic acid vinegar __ Cyclone type epoxy resin containing decane Phenol F type epoxy resin *4 butyl stupyl ring-based propyl group blocked non-aromatic polyisocyanate (nonvolatile content 80%) * 5 closed non-aromatic polyisocyanate (nonvolatile content 80%) * Β methyl Hexahydrophthalic anhydride hydrogenated methyl nadic anhydride containing vinyl phenol resin

^glycidoxypropyltrimethoxymethane·^醯acetic acid alkyl ester diisopropoxy aluminum hydrazine 6 jade, 4-diamino-6-[2'-methylimidazolyl-(1,) ]-ethyl-all three ^__ fluorenyl-4_methyl_5. hydroxy hydrazinium _ ΪΤ8-diazabicyclo[5.4.0]-+ —桷-7 1 : ring amount = 290 g/eq (Average per molecule * 2 : Epoxy equivalent = 200 g / eq (average of 2 hydroxy groups per molecule) 320307 15 200908392 氺 3 : Epoxy when 1 = * 4 : Epoxy equivalent = i58g / eq * 5 · 〇本聚胺酉制制制制制 c〇ronate 2507 *6 :(18- 9-alkenyl-acetamidine acetate_〇ι,,〇3) dipropen-2-oxyaluminum*7: BET Flank silver powder with specific surface area 〇27m2/g, tap density 3.3g/cm3, D5〇 particle size 7.5/zm*A: epoxy equivalent = 1〇〇〇g/eq (average hydroxyl group per molecule) *B: Coronate B1301 manufactured by Sakamoto Polyurethane Industry Co., Ltd. As shown in Fig. 2, Examples 丨 to 4 and Comparative Example 2 using polyoxynoxy resin, even after long-time light irradiation, the reflectance is also It does not change, and it is known that the optical text is excellent in qualitative. As a matter of course, in the initial example, the 450 nm (wavelength) reflectance Xa is 42 2%, and the light irradiation is 1〇. After a few hours, the reflectance xb was 33.8%, and Xb/Xa was 0.8. In Example 2, the reflectance xa of the initial Onm was 29.4%, and the reflectance after the light irradiation for 1 hour was 3.3%. Xb/Xa is 1 〇 5. In Example 3, the initial reflectance Xa is 30, and the reflectance along the light after 1 hr is 23.6/, and Xb/xa is 〇78. Example 4 is in the early stage. The reflection rate after the reflection of (10) is less than that of the hair of the hair. On the other hand, in the comparative example i in which the base of the epoxy resin is outside the (fourth) of the month and the acid anhydride-based hardener is used,反射The rate of deterioration of the reflectance occurs slowly. In the case of using 方 裱 裱 裱 裱 * 巾 巾 巾 巾 巾 巾 巾 巾 巾 巾 巾 巾 反射 反射 反射 反射 反射 反射 反射 反射 反射 反射 反射 反射 反射 反射 反射 反射 反射 反射 反射 反射 反射 反射 反射In the comparative example 5 in which 32307 16 200908392 peeling (confirmation of choking phenomenon) and no blocked isocyanate was used between the time and the glass substrate, some reflectance deterioration occurred. As shown in Fig. 4, 3回流 of the predetermined reflow. (: Temperature cycling with room temperature 'Examples 1 to 4, Comparative Examples 3 and 4 are stable. In the comparative example 1, it is seen that the resistance value is somewhat dispersed. On the other hand, in the comparative example 2 using the poly-resin resin, not only the correctable resistance value but also the "resistance value" can be seen. It is presumed that this is due to the presence of the Shixia oxygen-burning skeleton in the scorpion scorpion, which causes the thermal fluctuation to become large and the strength to be low. In Comparative Example 5 in which the blocked isocyanuric acid was not used, not only the resistance value was largely dispersed, but also the increase in the resistance value was observed. Further, = the second figure does not, even in the case of a predetermined moisture absorption reflow and a more severe temperature cycle, only % of examples 1 to 4 are still stable and exhibit a low resistance value. As shown in Fig. 7, Comparative Example 2, which is pure to use (iv) an oxygen resin, exhibits a preferred shear strength at room temperature. The shear strength of Example 1 and Comparative = Temperature was also higher. Further, as shown in Fig. 8, even in the case of the color-adjusting HID lamp, no deterioration was observed. The values of Examples 1 to 4 were not the same, and none of Comparative Examples 1 and 2 changed the viscosity at 24 hours. 2. It is understood that when an acid anhydride-based curing agent is used, the application period is difficult to satisfy the viscosity stability of Examples 1 to 4, Comparative Examples 3 and 4, and it is remarkable: I is used. In particular, the viscosity of Example 1 was small, and it was found that workability and the like were excellent, and not only the stability of the calendering property was excellent, but also the conductive die attach adhesive for LED of the present invention was also in terms of shear strength and electric resistance value. 320307 200908392 It is excellent, and it can provide connection reliability and it can be obtained even at high temperatures. Especially, the resistance value changes, so it is excellent. It is 3 degrees better, and it can suppress the electric motor in the operation (4). The phase is also excellent in phase, (industrial availability). Conductive grain adhesives for fish can provide reliable connection. [Simple illustration] It is helpful for developers of coffee. Figure 1 is the wavelength of the blue hid lamp. Fig. 2 is a graph showing changes in the day π M a f t of the lamp from the blue ΗΠ). The reflectance caused by the lamp is shown in Fig. 3. The method for producing the sample for measuring the resistance value is... the eight graphs are not prepared in the opposite direction, the third graph is shown in Fig. 3_B, and the panel is shown in Fig. 3D. The figure shows the seal. The :4 figure shows a graph of the change in resistance value under the condition of predetermined reflow. Figure 5 is a graph showing the conditions under the predetermined moisture absorption reflow. ^ & Figure 6 is a schematic diagram of shear strength measurement. Figure 7 is a graph showing the values of shear strength at room temperature and elevated temperature. Figure 8 is a graph showing the change in shear caused by illumination of a blue HID lamp. Figure 9 is a graph showing the change in viscosity. [Main component symbol description] 320307 18

Claims (1)

200908392 X. Patent application scope: 1. A conductive die attaching agent for LEDs, comprising: (A) a lipid-resin containing an average of more than 5 hydroxyl groups per molecule, ^ % ^ (B) non-aromatic A blocked block of a polyisocyanate, and (C) a conductive filler. 2. The die attach adhesive of claim 1, wherein the hydrogenated epoxy resin of the following formula is: 77 (wherein 'X is -CH2·, -C(CH1 2 3)2· or direct bonding; m is an average of 0.5 or more). The invention relates to a die attaching agent according to claim 1 or 2, wherein the component (B) is obtained by blocking an aliphatic diisocyanate with a lanthanoid compound or an indoleamine compound. Blocking compound. The die attaching agent according to any one of claims 1 to 3, wherein the '(C) component is a silver powder. 3. The die attaching agent of any one of claims 1 to 4, wherein the total amount of the components (A), (B) and (C) is 1 part by weight, (A) The component is 2 to 15 parts by weight, the component (B) is from 0.01 to 11 parts by weight, and the component (C) is from 74 to 97 parts by weight. 6. The grain spotting agent as claimed in any one of claims 1 to 5, which comprises (D) a chelate compound of aluminum. 200908392 7. The die attach adhesive according to any one of claims 1 to 6, which further comprises (E) a breaker coupling agent. 8. The die attaching agent according to any one of claims 1 to 7, wherein the die attaching agent is applied to a glass substrate at a thickness of 150 // m at 150 ° C The film was heat-hardened for 2 hours, and then cooled to room temperature to obtain a coating film, and the initial reflectance Xa of the coating film was 4 5 nm (wavelength), and the blue HID lamp (400 W, 8000 Lm, 20000 Lx) was used for the coating film. The reflectance Xb of 450 nm after a distance of 50 mm at 150 ° C for 1000 hours satisfies Xb / Xa2 0.75. An LED manufactured by using the die attaching agent of any one of claims 1 to 8. 20 320307