How Scanning tunneling Microscope works ?
Scanning tunneling microscope scans the electrons at fixed distance. First, a voltage bias is applied and the conducting tip is placed closer to the sample to be examined.The tip is also known as stylus ,stylus is extremly sharp and usually made up of a finnest diamond , which is swiched off when the tip and sample are sufficiently close. When a conducting edge or tip is brought near the surface to be tested, a specific voltage variation is applied which allows electrons to pass through the tunnel in the vaccum.In the result, tunneling current is obtained which is the function of accurate tip position. Information is gathered by monitoring the current according to the tip position which scans across the surface, and this information is usually displayed in form of image. The stylus is moved in the upward direction and then lowered in order to keep the each signal undistorted .This allows it to follow even the smallest data of the surface it is scanning. Storing the vertical movement of
