| 摘要 |
<p>Two layers of protection films (8, 9) are formed such that a sheet resistance at a part directly below the protection film (8) is higher than that at a part directly below the protection film (9). The protection films (8, 9) are formed of, for instance, a SiN film, as insulating films. The protection film (8) is formed with a hydrogen concentration higher than that of, for instance, the protection film (9) so that the refractive index of the protection film (8) is higher than that of the protection film (9). The protection film (8) is formed to cover a gate electrode (7) and extend to the vicinity of the gate electrode (7) on an electron supplying layer (3). The protection film (9) is formed over the entire surface to cover the protection film (8). Thus, a highly reliable compound semiconductor device wherein a gate leak is remarkably reduced with the relatively simple configuration and high voltage operation, high withstand voltage and high output are achieved is provided.</p> |
