| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a substrate flatening material useful for a wiring substrate and a semiconductor element, etc., having level difference or unevenness, comprising a linear siloxane-based polymer containing a silphenylene bonding in a molecule skeleton. SOLUTION: This material is a polymer of formula I having 500-50,000 weight-average molecular weight (R<1> -R<4> are each a 1-3C alkyl or a 2C or a 3C alkylene; (n) is a positive integer) or a polymer of formula II having 500-50,000 weight-average molecular weight (R<5> and R<6> are each a 1-3C alkyl or a 2C or a 3C alkylene; (m) and (n) are each a positive integer and a ratio of (m) to (n) is (m/m)<2). As the polymer of formula I, polytetramethyl silphenylene siloxane, polytetraethyl silphenylene siloxane, etc., is exemplified. As the copolymer of formula II, poly(tetramethyl silphenylene siloxane/divinyl siloxane) copolymer, etc., is exemplified. The flattening material is applied on the uneven surface of the substrate, heated to reflow to flatten the substrate surface.</p> |
