SEMICONDUCTOR DEVICE AND ITS MANUFACTURING METHOD

PROBLEM TO BE SOLVED: To provide a semiconductor device wherein heat dissipating performance is improved without obstructing high speed and high level integration of a semiconductor element which are achieved by SOI technique and obstructing miniaturization of a package which is achieved by flip chip mounting, and to provide a method for manufacturing the device. SOLUTION: In the semiconductor device 101 wherein a semiconductor layer 10 is laminated on a retaining substrate 11, semiconductor elements 81-83 are formed on a first surface 70 on a semiconductor layer 10 side, trenches 2 are formed from a second surface 71 on a retaining substrate 11 side toward the semiconductor layer 10, and the insides of the trenches 2 are filled and formed with high thermal conducting material 3 whose thermal conductivity is greater than that of the retaining substrate 11, and heat dissipating performance of the semiconductor device 101 is improved. COPYRIGHT: (C)2004,JPO