Formation of nanoconstriction in thin insulating films by applying electric field.

金属（Al）/绝缘子（SiO_2和/或MgO）/金属（Au）堆叠在薄（5- 20 nm）绝缘膜上的结构已制造。通过applying d. c. voltage的电绝缘状态更改通过调节状态（V_t）实现调节状态（V_t）的阈值电压，即SiO_2 （t_<SiO2>）和MgO （t_<MgO>） films的thickness的一个功能，响应。结果如下：适用于SiO2薄膜，V_t [V] =0.7 [V/nm] ·t_<SiO2>[nm]，适用于MgO薄膜，V_t [V] =0.44 [V/nm]·t_<MgO>[nm]。应用前和应用后都有使用扫描隧道显微镜（STM）观察的Au anodic表面。关于Au anodic表面的形态学被改变以使每个过程在绝缘薄膜中形成纳米结构。目前的实验揭示了一个事实，即MIM结构形式中的电变化，以使其与纳米结构的形成与其表面的变形有关。

Metal (Al)/insulator (SiO_2 and/or MgO)/metal (Au) stacking structure with thin (5-20nm) insulating films have been fabricated. The electrically insulating state changes into conductive state by applying d.c. voltage.The threshold voltage from insulating state to conductive state (V_t) has been measured as a function of the thickness for SiO_2 (t_<SiO2>) and MgO (t_<MgO>) films, respectively. Results are as follows : for SiO2 films, V_t [V] =0.7 [V/nm] ・t_<SiO2> [nm], and for MgO films, V_t [V] =0.44 [V/nm]・t_<MgO> [nm].The Au anodic surfaces before and after applying field have been observed using scanning tunneling microscope (STM). The morphology on the Au anodic surface changed for the each process to form nanoconstrictions in the insulating films. Present experiment revealed the fact that the electrical change in the MIM structure form insulating to conducting related the formation of nanoconstriction due to the deformation of the surface of anodic material.