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Mesa- and planar-type InP metal/insulator/semiconductor field effect transistors (MISFETs) were fabricated on iron-doped semi-insulating substrates with plasma anodic Al 2 O 3 as the gate oxide. The characteristics of the MISFETs were measured with a curve tracer and by a pulse method. The effective channel mobilities obtained from these measurements for mesa-type and planar-type devices are 800–2500 cm 2 V -1 s -1 and 350–500 cm 2 V -1 s -1 respectively. The drift of the current-voltage characteristics was measured and is discussed.

Aluminium oxide-InP structures were fabricated by plasma anodization of evaporated Al-InP systems with intention of fabricating InP MISFETS. It was found that the resistivity and break-down strength of the A12O3 film were influenced by the selection of the end point of the anodization. At appropriate conditions the resistivity of 5 × 1010 − 1012Ω cm for the anodic Al2O3 and the minimum density of the interface trap states of 4 × 1011 cm−2 ev−1 for Al2 O3 -InP systems were obtained.

Metal‐insulator‐semiconductor diodes were fabricated on an n‐type GaAs substrate by means of plasma anodic oxidation of aluminum film evaporated on the GaAs substrate. The capacitance‐voltage (C‐V) characteristics of these diodes were significantly affected by the deposition rate of the aluminum onto the GaAs substrate. Depth profiles revealed by Auger electron spectroscopy show that the amount of gallium atoms migrated from the GaAs surface through the aluminum oxide film increases with decreasing the deposition rate of the aluminum. At the appropriate deposition rate, the C‐V curves show the increase of capacitance in negative‐bias (polarity of inversion) region at low frequency.

Thermal oxidation of GaAs has been carried out for temperature range between 470°C and 830°C in dry and wet atmosphere. The experimental results show that the oxidation rate and the properties of the oxide film are dependent on the surface orientation and surface treatment of the wafers and the oxidation condition. For temperature range between 470°C and 530°C the oxidation follows the linear oxidation relationship for wafers with (111), (110) and (100) surface etched by HF, and the oxide dissolves in HF solution. The activation energy of the rate constant is 2.2 eV, while the oxidation of the wafers with (100) surface dipped into methanol just before the oxidation follows the parabolic relationship and the oxide dissolves in boiling HCl.

Enhancement type InP metal‐insulator‐semiconductor field‐effect transistors were fabricated using plasma anodic aluminium oxide as the gate insulator. The effective electron mobilities in the surface channel are 1250 cm2/Vs and 2000 cm2/Vs at 300 and 80 K, respectively. The drift of the drain current at 300 K ceases a few minutes after applying a gate voltage and stable dc operation is observed over several hours.

The transition probability of a hot electron in metals due to phonons is calculated by using Bardeen's self-consistent field approach. The results show that the mean free path is slightly dependent on the initial energy of the electron. A hot electron in gold with an initial energy 1 eV higher than the Fermi energy has a calculated mean free path of 330 Å. The measured hot electron's attenuation length of 350 Å in gold can thus be explained by the present calculation, together with Quinn's result for the hot electron mean free path due to interaction with conduction electrons.