| 摘要 |
PURPOSE:To accurately evaluate MESFET characteristic by using the height of a Schottky barrier obtained by forward I-V characteristic of a gate electrode as an ideal factor value, and dividing the irregularity of the measured MESFET characteristic into the irregularities by the Schottky characteristic of the gate electrode and an active layer. CONSTITUTION:There are relationships of equations I and II among the height phiBO of a Schottky barrier obtained from the forward I-V characteristic of a gate electrode of MESFET, an ideal factor n value determined by a boundary state, K value and threshold value Vth obtained from Vgs-ID<1/2> based on ID=K (Vgs-Vth)<2>, where Vbi*, phiBF are the built-in voltage and the height of the Schottky barrier in a flat band state, phiBF is represented by an equation III (where Vn is the potential difference between Fermi level and conduction band) by using phiBO, n value obtained from forward I-V characteristics. Thus, the n value which preferably represents the boundary between a gate metal nd a semiconductor is employed to divide the irregularity of MESFET characteristic into the irregularities of the Schottky characteristic and the substrate active layer to be evaluated. |
