| 摘要 |
PURPOSE:To increase the height of a Schottky barrier, and reduce the gate leak current, by installing a Schottky gate electrode on a modulation doped AlInAs layer via an AlGaAs layer whose thickness is less than or equal to a threshold value generating lattice mismatching dislocation. CONSTITUTION:On a semiinsulative InP substrate 1, the following are provided; a high purity Ga0.47In0.53As layer 2 arranged in the lattice-matching manner, an Al0.48In0.52 As layer 4 which is lattice-matched with the layer 2 to form an electron storage layer 3 in the layer 2 and forms a hetero junction with discontinuity of a specific conduction band by doping N-type impurity at least in a part, and a gate electrode 7 which is in contact with the layer 4, arranged via an Al0.4Ga0.6As (0<x<1) layer 5 of 2nm thick being less than or equal to threshold film thickness generating lattice mismatching dislocation, and controls the electron concentration of the electron storage layer 3 in the layer 2. In this constitution, lattice mismatch exists between Al0.48In0.52As and AlxGa1-x, so that an AlxGa1-xAs layer whose thickness is less than or equal to the threshold film thickness generating dislocation due to lattice mismatching is installed as a means to evade the lattice mismatching. Thereby, the effective height of a Schottky barrier is increased in the state without generating dislocation, so that the gate leak current can be reduced. |
