Sealing film and a semiconductor device using the same

A method for sealing electrodes on a semiconductor using a sealing film, comprising the steps of:

• providing a sealing film which comprises a resin layer containing the following (A), (B) and (C) and having a viscosity within the range of 10000 to 100000 Pa·s in a B-stage state at 50 to 100° C. in thermosetting viscoelasticity measurement:
• (A) a resin component containing (a1) a high-molecular-weight component comprising crosslinking functional groups and having a weight-average molecular weight of 100,000 or more and a Tg within the range of −50 to 50° C. and (a2) a thermosetting component comprising an epoxy resin as a main component,
• (B) a filler having an average particle size within the range of 1 to 30 μm, and
• (C) a colorant, and
• wherein the sealing film contains 1 to 300 parts by mass of the filler (B) and 0.01 to 10 parts by mass of the colorant (C), based on 10 parts by mass of the resin component (A) containing 5 to 85% by mass of the high-molecular-weight component (a1) and 15 to 95% by mass of the thermosetting component (a2);
• laminating the sealing film by a lamination roll to contact the resin layer with an electrode surface of the semiconductor substrate;
• and
• sealing the electrodes on the semiconductor substrate.