Scanning tunneling potentio-spectroscopic microscope and a data detecting method

摘要

A scanning tunneling potentio-spectroscopic microscope, includes a conductive probe and a circuit for selectively applying one of first, second and third bias voltages to a sample. A tunnel current flowing between the probe and sample is detected, and a tunnel current signal is produced upon detection thereof. A servo circuit controls a distance between the probe and sample on the basis of the tunnel current signal by producing a servo signal as a feedback signal. A hold circuit switches the servo circuit between operating and non-operating states. Configuration data on a surface of the sample is obtained, on the basis of the servo signal, with the first bias voltage applied to the sample and with the servo circuit in the operating state. A first dependence of the tunnel current on the bias voltage is obtained, from the tunnel current signal and the second bias voltage, with the second bias voltage applied to the sample and with the servo circuit in the non-operating state. A second dependence of the tunnel current on the bias voltage is obtained from the tunnel current signal and the third bias voltage, with the third bias voltage applied to the sample and with the servo circuit in the non-operating state. Electron state data is obtained on the basis of the first dependence, and potential data is obtained on the basis of the first and second dependencies.