THERMOSETTING RESIN SHEET, SEMICONDUCTOR DEVICE, AND MANUFACTURING METHOD OF SEMICONDUCTOR DEVICE

PROBLEM TO BE SOLVED: To efficiently discharge a gas existing between a thermosetting resin sheet and a component and in the thermosetting resin sheet to the exterior of a resin during heat hardening by forming slits in the thermosetting resin sheet in advance.SOLUTION: A semiconductor device includes: a semiconductor substrate 1; a semiconductor component 2 mounted on the semiconductor substrate 1; a thermosetting resin sheet 3 having an area larger than an area of the semiconductor component 2 and having multiple slits 6. The slits 6 are provided in at least an entire region where the semiconductor component 2 is mounted and an area surrounding the region, and the semiconductor component 2 is sealed by the thermosetting resin sheet 3 and the semiconductor substrate 1.