Atomic scale extraction of hydrogen atoms adsorbed on Si(001) with the scanning tunneling microscope

Atomic scale extraction of hydrogen atoms on Si(001)-(2 × 1)-H and -(3 × 1)-H surfaces between 300 and 610 K have been studied using a scanning tunneling microscope. Hydrogen atoms were extracted at positive and negative sample bias voltage. Site-selective desorption and reconstruction from the dihydride phase to the monohydride phase are found in the desorption of hydrogen atoms from Si(001)-(3 × 1)-H surfaces. STM-induced desorption of H atoms on a Si(001)-(3 × 1)-H surface occurs preferentially at dihydride units rather than monohydride units. The results support an electric field induced desorption.