| Since the1980s, the development of semiconductor industry was miniaturization,high integration, good reliability and flattened. The degree of integration wasdeveloping at a surprising rate every three years on average increased by4times.Integrated circuit （IC） is constituted of fine elements on the silicon chip and precisionof the line. Electronic packaging techenology is the key to this problem: outside dust,heat, moisture and mechanical shock. Furthermore, packaging techenology also playsas mechanical support and cooling functions.Epoxy molding plastic as microelectronics packaging material has become themost important packaging materials, because its low cost, high performance andreliability. Currently, more than95%of IC used epoxy molding compound aselectronic package material. In recent years, epoxy resin package molding compoundfollowed by the the rapid development of ultra-high-ICs. Although, new varietiesconstantly emerge, there also were some challenges. High temperature and low waterabsorption have always been purposed in high-performance epoxy moldingcompound. The epoxy molding resistance performance depended on the heatdistortion temperature and thermal oxidative stability of the cured product. Epoxymolding after absorption of mosture will lead to deterioration of the electricalproperties, mechanical properties and thermal stability, moreover, package crackingphenomenon occurs after expansion and vaporization of the water molecules, Focus on heat-resistant epoxy molding compound, the current approach was: onone hand, decreasing moisture absorption of the resin by introducing fluorine, siliconeand sulfone group, reducing the free volume and reducing the concentration of polargroups mehod to solve water absorption rate; on the other hand, introducing heatexcellent functional groups, such as biphenyl, heterocycle, naphthalene ring and so on.In the case of other performance did not decrease, the more heat rigid radicals, thegreater the high temperature mechanical properties and the heat resistance. Therefore,how to solve the epoxy molding compound and keeping a higher resistance andmaintains low water absorption was very necessary.The purpose of this article was to prepare a high-performance epoxy resin. Frommolecular design, biphenyl, a trifluoromethyl group, a naphthalene ring, a methylgroup and methylene structure were introduced into the molecular structure,expectantly, epoxy resin were both a superior high temperature performance andmoisture resistant packaging materials. In addition, blending a biphenyl structure ofthe epoxy resin not only improved the heat resistance and the glass transitiontemperature, but also decreased the water absorption of the epoxy molding compound.-SO2-group had a higher electron cloud density than-C （CH3）2-group. BisphenolS epoxy resin exhibited a better performance than the bisphenol A epoxy resin. Firstby nucleophilic substitution reaction, bisphenol S and epichlorohydrin react underphase transfer catalyst. The amount of epichlorohydrin used in the synthesis process,the selection of phase-transfer catalyst, the amount of the alkali, the concentration ofalkali and the adding methods were discussed in detail, and the yield and the epoxyvalue were to evaluate the best synyhesis process. This process was simple and rapid,getting produce by the precipitated method. Epoxy exhibited its value in applicationwhen forming a three-dimensional network of insoluble and infusible with a curingagent. Therefore, we used three typical agents, aromatic amines, imidazole and acidanhydride, with non-isothermal method of DSC, discussed each curing agent underthe curing temperature and the curing kinetics. Coats-Redfern formula obtained adifferent degree of the apparent activation energy Ea. Ea increaseed with the conductof the reaction, indicating that the reaction was more difficult in the end of reaction. Curing mechanism of bisphenol S epoxy resin and the three type curing agents werediscussed in detail.Seconly, starting from molecular design, both containing a biphenyl structure,and a trifluoromethyl group-containing epoxy resin was prepared. By diazotization,coupling reaction and the reduction reaction, prepared trifluoromethylphenylhydroquinone. By nucleophilic substitution reaction, the two-step method synthesizedtrifluoromethylphenyl epoxy containing fluorine in the side chain. Since the3F-PQEcontained rigid biphenyl structure, all the curing system had a better thermal stability.All the IPDTs were more than410oC. Rigid DDM curing system owned a high glasstransition temperature. By introduction of the fluorine element, the contact angle ofthe four curing system were greater than90°, and3F-PQE-PA surface of the curedself-assembled, the contact angle was105.5°. DDM and PA curing systems alsoexhibit lower water absorption.Since the fluorined epoxy resin was relatively expensive, therefore, in chapterfive, by molecular design, prepared by a novel epoxy resin containing a biphenylstructure and a methyl group side chains. The glass transition temperature wasmeasured by DSC and DMA.4M-PQE/DDM had the highest glass transitiontemperature. The thermal stability of cure system: the aliphatic chain polyetheramines D230relative worst, DDM curing system of the aromatic amine had the bestthermal stability. IPDT values were more than400oC. DDM and PA system ownedlow water absorption. Imidazole ring of2MI with water could form hydrogen bonds,therefore, the water absorption increased. Naphthalene skeleton-containing epoxyresin was hot in the electronics packing field, a naphthalene ring could greatlyimprove Tg and thermal stability. Therefore, we designed an epoxy resin containing anaphthalene ring and a benzoyl group, which had a good heat-resistant property.Usually, the introduction of the flexible segment and the hard segment in themain chain improved the comprehensive performance of the material. Based on theabove principles, in the chapter six of this thesis, we had designed a new type ofepoxy resin that was introduced between the structure of the benzene ring of thebiphenyl-CH2-group, compared with the structure of the methylene bisphenol A type epoxy isopropyl group, there was a greater rotational reduced rigidity, increasing theflexibility and improving the use of beneficial processing. By aldol condensationreaction, and bit barrier effect of methyl groups on the benzene ring, to prevent theformation of byproducts, the successful synthetized of tetramethyl bisphenol F. Byelectrophilic substitution reaction, tetramethyl bisphenol F epoxy resin were synthesisby two-step process. Then, tetramethyl bisphenol F epoxy resin was blending with abiphenyl epoxy resin. With DDM curing agent, the tendency of Tg increased withincreasing the content of TMBP. Introduce huge biphenyl rigid segments, the chainmight be the proportion of internal rotation of a single bond occurred relativelyreduced, relatively difficult to rotate within, and thus obtained a high Tg and heatresistance temperature. All the curing system had lower water absorption. |
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