About a change of the threshold voltage at nanostructure formation in the scanning tunneling microscope

It is shown that the process of nanostructure formation is determined in many respects by parameters of the electrical circuit used in the STM . The hills formation probability from the applying voltage pulse U_pulse for various quantities of an impedance of the preliminary amplifier (PA) and for various quantities of additional resistor R_x is investigated. A change of the impedance PA is carried out by the additional capacity C_x. This capacitor shunts an entering impedance PA. Connection C_x results in a change of a threshold voltage U_th of nanostructure formation. The threshold voltage decreases with a reduction of an entering impedance (increase C_x). Such behaviour of U_th argues for the mechanism of thermal expansion tip