Study of electrical properties of ultra-thin Na films on Si(100)

The surface conductivity of samples with the Si(100)3 x 2-Na surface phase was measured in ultra-high vacuum by four-point probe method at room temperature (RT). It was found that the difference in surface conductivity of a surface with Si(100)3 x 2-Na surface phase and that of a clean Si(100)2 x 1 surface is (-1,5 +/- 0, 8) . 10(-5) Ohm(-1) square. During the exposure in atomic hydrogen, the 3 x 2-Na surface phase is destroyed which leads to the decrease in surface conductivity. Further exposure reduces surface conductivity due to the formation of a new dihydride Si(100)1 x 1-H(Na) phase.