Semiconductor device, semiconductor module, and wireless communication apparatus

A semiconductor device (1) having high heat dissipation and high operational reliability is provided. This semiconductor device is provided with: a semiconductor substrate (10); a first semiconductor layer (20) provided on the semiconductor substrate, having a first opening (20K), and having a first thermal conductivity; a transistor (Tr) provided on the first semiconductor layer; and a heat dissipation unit (40) in contact with the semiconductor substrate via the first opening and having a second thermal conductivity higher than the first thermal conductivity. 提供了具有高散热性和高操作可靠性的半导体设备(1)。该半导体设备包括：半导体基板(10)；设置在半导体基板上、具有第一开口(20K)、并且具有第一热导率的第一半导体层(20)；设置在第一半导体层上的晶体管(Tr)；以及经由第一开口与半导体基板接触并具有高于第一热导率的第二热导率的散热单元(40)。