| 摘要 |
PURPOSE:To obtain an MESFET having low source resistance and low gate resistance, and having a superior withstand voltage by a method wherein the under part of a gate electrode metal in the neighborhood of the part to come in contact with an active region is formed in narrower width in the gate length direction as compared with the top part, and moreover the under part wall faces of the gate electrode metal are protected by insulating films. CONSTITUTION:The sectional shape of a gate electrode 24 formed on an active region 22 forms a narrow width part narrowed in width in the gate length direction at the under part in the neighborhood of the part to come in contact with the active region 22, the top part is a broad width part making the edge parts to reach a pair of high electron concentration regions 23, and forms nearly a T-shape. The distance between the high electron concentration regions 23 for a source and a drain on both the sides interposing the active region 22 between them is formed sufficiently shorter than size of the top part of the gate electrode 24, and formed longer than size in the gate length direction of the gate electrode at the part of the contact face with the active region 22. Moreover the side wall faces of the under part of the gate electrode 24 are made in structure protected by third insulating films 29 consisting of an Si3N4 film having superior humidity resistance, for example, and moreover, the upper parts of the high electron concentration regions 23 adjoining to the third insulating films 29 thereof are made in structure covered with second insulating films 28 consisting of an SiO2 film. |
