| 摘要 |
PURPOSE:To obtain a short-channel Schottky gate type field-effect transistor with the favorable characteristics, in which no abnormal phenomenon is generated, by a method wherein the depth of the N<+> type contact layers, which is measured from the surface of the active layer, and the distance between the contact layers are set in the specific relation. CONSTITUTION:The thickness of an N type active layer 13, the thickness of N<+> type contact layers 12 and the distance between the contact layers 12 are respectively assumed to be do, dc and Lc. Current ISUB 17, which flows in between the N<+> type contact layers 12 through a semiinsulative GaAs substrate 11 and flows on the part between the contact layers in the substrate 11, is proportioned to the impressing voltage VDS to be applied to the drain; the higher the voltage to be applied to the drain is, the larger the drain conductance gd is and the deterioration of the characteristics of the short-channel Schottky gate type field-effect transistor results in being brought. However, when the dc and the Lc are set so that the current ISUB 17 becomes about 5% or less of the maximum current to flow on the drain at practical saturated region, the effect due to the current ISUB can be almost ignored in the actual characteristics of the FET. As a result, the favorable characteristics of the short-channel FET, which have the small drain inductance gd, can be obtained. |
