In a high-frequency circuit, it is necessary to provide galvanic blocking between active elements such as transistors and between an active element and an external terminal, and thus MIM capacitors or the like are used frequently. A MIM capacitor coupled to an external terminal is easily affected by static electricity from outside and causes a problem of electro-static breakdown or the like. In a MIM capacitor formed over a semi-insulating compound semiconductor substrate, a first electrode thereof is coupled to an external pad and to the semi-insulating compound semiconductor substrate, and a second electrode thereof is coupled to the semi-insulating compound semiconductor substrate.