| 摘要 |
PURPOSE:To manufacture a filler of a good coating performance capable of breaking alpha line, by refining silicon compound and aluminum compound by distillation so that uranium and thorium contents become prescribed amounts and then oxidizing them by heating. CONSTITUTION:A silica compound, such as tetraethoxisilane, etc. and an aluminum compound, such as ethyl acetate aluminum diisopropylate, etc. are mixed with resin and the refined by distillation so that to total content of uranium and thorium becomes less than 0.2ppb. And then this is heated and oxidized to form a silica- alumina type filler which is composed of SiO2-Al2O3 (containing carbon) and has a good coating performance. When this filler is used by being mixed with a resin such as epoxy resin, etc., it is possible to cover a semiconductor memory element with a good alpha-line-breaking characteristics and coating performance. Further, in the case of a silica compound and an aluminum compound provided with hydrolysable group combined with silica and aluminum, these compounds may well be refined by distillation, hydrolyzed and then heated for oxidation. |
