Curable organopolysiloxane composition and semiconductor device

A thermally conductive cured product obtained by curing at 80 to 180° C. a curable organopolysiloxane composition in the form of grease or paste, said curable composition comprising:

• (A) 100 parts by weight of an organopolysiloxane having at least two alkenyl groups bonded to silicon atom in one molecule;
• (B) an organohydrogenpolysiloxane having at least two hydrogen atoms bonded to silicone atom in the molecule in such an amount that the number of the hydrogen atoms bonded to the silicon atom in component (B) is at 0.1 to 5.0 per one alkenyl group in component (A);
• (C) 7,000 to 20,000 parts by weight of gallium and/or a gallium alloy having a melting point of 0 to 70° C.;
• (D) 10 to 1,000 parts by weight of a thermally conductive filler having an average particle size of 0.1 to 100 μm;
• (E) 0.1 to 500 ppm, relative to the weight of component (A), of a platinum-based catalyst;
• and
• (G) 20 to 500 parts by weight of a polysiloxane of the following general formula (1):
• wherein R1 may be the same or different and represents a monovalent hydrocarbon group, R2 represents an alkyl group, an alkoxyl group, an alkenyl group or an acyl group, a is an integer of 5 to 100, and b is an integer of 1 to 3.