Semiconductor device and liquid jet apparatus using the same

摘要

A semiconductor device having a high source breakdown voltage and high performance and high reliability and a liquid jet apparatus are provided. In a semiconductor device having a switching element for flowing current through a load and a circuit for driving the switching element, respectively formed on the same substrate, the circuit has a source follower transistor for generating a drive voltage to be applied to a control electrode of the switching element, and the source region of the source follower transistor has a first doped region connected to the source electrode and a second doped region having an impurity concentration lower than that of the first doped region, the second doped region forming a pn junction with a semiconductor region forming a channel.