| 摘要 |
PURPOSE:To reduce the contact resistance of an electrode and to lessen the resistance between an active region and source and drain layers, by increasing the carrier density of the source and drain layers without losing the advantage of a self-alignment method in FET using a compound semiconductor. CONSTITUTION:With an SiO2 mask provided on a half-insulating GaAs substrate 11, Si ions are implanted to form source and drain layers 13 and a gate active region 14. Then, covered with an SiO2 film 15, the layers 13 and the region 14 are subjected to heat treatment to be activated. Holes are made in the film 15, a high-melting-point metal gate electrode 16 is formed on the region 14, and Si ions are implanted to form a layer 17 by self alignment. Then, covering is made with an SiO2 film 18, and the layer 17 is subjected to heat treatment to be activated. Thereafter, electrodes 19 are formed on the layers 13 as usual, and thus a Schottky barrier type FET is completed. By this constitution, the activation temperature of the layers 13 can be raised to about 850 deg.C. Therefore the activation proceeds sufficiently, the fall of the density on the surface of the substrate is very small, and the contact resistance can be reduced to about 1/10 of the usual one. |
