Study Of The Dos At The Junction Of In-,Si-addimer Row Located On The Top Of D-a Row Of Si(5512) By The Using UHV-STM

Fabrication method of the thickness tunable one-dimensional atomic Indium wire on the Si(5512) surface is studied. It is found that the density of state on the top of In-addimer row at the junction between Si-addimer and In-addimer rows, which is located on the top of D-A row of Si(5512)-2x1substrate surface, is much higher in the filled state STM image. But in empty state STM image is not. Not only for understand this pronounced phenomena, but also for the importance of the probability of which is the formation the atomic scale diode. For the confirmation of this kind of discovery is or not done by other research groups, review of the references has been performed as follows:1. Temperature variation influences the structure deformation and therefor transforms the distribution of the electron density of state in one-dimensional atomic row.2. When the Ga is adsorbed on the surface of Si (001), the distribution of electron density of state of Ga-addimer is affected by the beneath Si-dimer of the substrate surface.3. The distribution of electron density of state is also affected by the arranged dangling-bond number in a row of the one-dimensional monatomic line.4. The distribution of electron density of state of the single-atom in1-D row is different according to the location site.5. The existence of defect lead to the redistribution of the electron density distribution. Summarization of this review:the distribution of electron density of state is influence by several kinds of effect; and the nature of the existence of the fluctuation and redistribution of the charge density, the density of state of the electrons on the surface dangling bonds can transform to the nearest one easily. The experimental phenomenon of the system analysis are:firstly, Indium is a trivalent element. When it is adsorbed on the surface of Si and formed the In-addimer, each In atom contains4sp3like bonds, three are covalent bond with the adjacent atoms of the substrate surface. The remaining one is an empty orbital without combination, that is empty dangling bond. Si is tetravalent element, every Si atom in surface Si-addimer contains4sp3like bonds, likewise, three covalent bond with the adjacent atoms, the remaining one has an electron filled, that is one electronic dangling bond remain. Therefore, the brightness of In-addimer is higher than Si-addimer in the empty-state STM. In the filled-state of STM image, the brightness of In-addimer seems to be lower than that of Si-addimer. But, the observated result is that the center of In-addimer chain is really dark than Si-addimer, but the In-addimer is brighter than the Si-addimer at the junction site between the In-addimer and Si-addimer. Because of the distribution of electron density of state on dangling bonds is disturbed and redistributed easy. So the electron in Si dangling bonds can easily move to the In empty dangling bond, which leading to increase of the Fermi-level of the dangling bonds, so the electron density for the contribution to the tunnel current increased. Finally, on the endpoint position of In-addimer row, in the filled-state STM image appear very bright. This phenomenon is the micro process of the electron diffusion from the N type semiconductor to the P type semiconductor, i.e., the depletion in atomic scale is observed.