Semiconductor device with T-shaped gate electrode and hollow region adjacent the gate electrode

摘要

In a semiconductor device, a SiN first protective insulating film is formed on a semiconductor layer. A T-shaped gate electrode is formed on the semiconductor layer. A SiN second protective insulating film spreads in an umbrella shape from above the T-shaped gate electrode. A hollow region is formed between the two SiN films. The SiN films are coated with a SiN third protective insulating film with the hollow region remaining.