The present disclosure relates to a semiconductor device, an electronic device, and a manufacturing method that can maintain the mounting reliability of an underfill. A chip is formed by a circuit of an imaging element being produced on a Si substrate that is a first substrate and a second substrate being produced on an adhesive formed on the circuit. In this event, a photosensitive material is formed around the chip after the chip is mounted on a mounting substrate by a solder ball or in the state of the chip, then an underfill is formed, and then only the photosensitive material is dissolved. The present disclosure can be applied to, for example, a CMOS solid-state imaging sensor used for an imaging device such as a camera.