ULTRAFAST METAL-SEMICONDUCTOR-METAL PHOTOCONDUCTIVE SWITCHES FABRICATED USING AN ATOMIC-FORCE MICROSCOPE

The oxidation using an atomic force microscope was applied in the fabr ication of ultrafast metal-semiconductor-metal photoconductive switche s. The photoconductive gap was formed by the oxidation of a 4 nm-thick -titanium layer. The photoconductive gap which was 100 nm wide and cov ered with the oxidized titanium which is not only a good insulator but also transparent to the excitation Learn. A full width at half-maximu m response of 380 fs was obtained at a bias voltage of 10 V.