Threshold voltage controls of Ni/Ti/Au gate and Ti/Au gate two-dimensional electron gas (2DEG) AlGaAs/GaAs FETs through only heat treatment are investigated. Ni/Ti/Au gate FETs vary over quite a wide range from a depletion mode to an enhancement mode without degradation of FET characteristics after heat treatment at 300 degree C. The same experiment is made for Ti/Au gate FETs, but the threshold voltage change is negligibly small. It is confirmed that Ni/Ti/Au can be used as the gate metal for E-FET and Ti/Au as the gate metal for D-FET under simultaneous heat treatment. In addition, a mechanism for penetrating the barrier metal into the underlying layer is discussed.
|ジャーナル||Electron device letters|
|出版物ステータス||Published - 1984 7|
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