Electronic transport properties of surface-state bands on semiconductors

半导体表面态带的电子输运特性

• 批准号: 10650025
• 负责人: HASEGAWA Shuji
• 金额: $ 2.56万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10650025/
• 关键词: surface electronic transport; surface-state band; surface superstructure; semiconductor; two-dimensional electron system; RHEED; epitaxy; magneto resistance

(1) We have developed an RHEED sample holder for surface conductivity measurements at low temperatures in ultrahigh vacuum, and installed it in a UHV-RHEED chamber with a superconducting magnet to measure Hall effect and magnetoresistance.(2) Temperature dependence of surface conductivity of Si(111)-ィイD83ィエD8 X ィイD83ィエD8-Ag and ィイD821ィエD8 X ィイD821ィエD8-Ag surfaces was measured in a range of 40 to 300 K. In a temperature range of 100 to 300K, the conductivity of the ィイD821ィエD8 X ィイD821ィエD8 was the highest while that of the 7 X 7 was the lowest. The conductivity of the Ag-covered surfaces increased with temperature lowering, meaning a metallic conductivity. Below 100K, the 7 X 7 surface showed the highest conductivity.(3) Magnetoresistance of Bi atomic layers on Si(111) surface was measured under a magnetic field up to 6 T at room temperature. The resistance changed by a few %.(4) A ィイD83ィエD8 X ィイD83ィエD8 surface superstructure induced by 1/3 monolayer Sn adsorption on Si(111) surface was found to show a phase transition into a 3 X 3 phase by cooling down to around 100 K. This may be a charge-density wave transition, similar to that observed on Sn-covered Ge(111) surface.

(1)我们研制了一种用于超真空低温表面电导测量的RHEED样品保持器，并将其安装在带有超导磁体的超高压RHEED室中，用于测量霍尔效应和磁阻。(2)在40 ~ 300 K范围内，测量了Si（111）-Si_（111）D_83）D_8 × Si_（111）D_83）D_8-Ag和Si_（111）D_821）D_8 × Si_（111）D_821）D_8-Ag表面的表面电导率随温度的变化。在100 ~ 300 K温度范围内，导电率最高的是D821-D8 × D821-D8，最低的是7 × 7。Ag覆盖的表面的导电性随着温度降低而增加，这意味着金属导电性。在100 K以下，7 × 7表面显示出最高的电导率。(3)在室温下，在高达6 T的磁场下，测量了Si（111）表面Bi原子层的磁电阻。电阻变化了几个百分点。(4)Sn在Si（111）表面上的1/3单层吸附诱导出的超结构为D_83 → D_8 × D_83 → D_8，当温度降至100 K时，超结构转变为3 × 3相。这可能是一个电荷密度波跃迁，类似于在Sn覆盖的Ge（111）表面上观察到的。

项目成果

S.Takeda,X.Tong,S.Ino,S.Hasegawa: "Structure-dependent electrical conductance through indium atomic layers on Si(111) surface" Surface Science. 415. 264-273 (1998)

S.Takeda、X.Tong、S.Ino、S.Hasekawa：“Si(111) 表面上铟原子层的结构依赖性电导”表面科学。

D.A.Tsukanov,S.V.Ryzhkov,S.Hasegawa,V.G.Lifshits: "Surface conductivity of submonolayer Au/Si system"Physics of Low-Dimensional Structures. 7/8. 149-154 (1999)

D.A.Tsukanov、S.V.Ryzhkov、S.Hasekawa、V.G.Lifshits：“亚单层 Au/Si 系统的表面电导率”低维结构物理学。

C.-S.Jiang,S.Hasegawa: "Photoconductivity of the Si(111)-7×7 and √<3>×√<3>-Ag surfaces"Sarface Science. 427/428. 239-244 (1999)

C.-S.Jiang、S.Hasekawa：“Si(111)-7×7 和 √<3>×√<3>-Ag 表面的光电导性”表面科学 427/428 (1999)。

T.Nagao,S.Ohuchi,Y.Matsuoka,S.Hasegawa: "Morphology of ultrathin manganese silicide on Si(111)" Surface Science. 419. 134-143 (1999)

T.Nagao，S.Ohuchi，Y.Matsuoka，S.Hasekawa：“Si（111）上超薄硅化锰的形态”表面科学。

N.Sato,T.Nagao,S.Takeda,S.Hasegawa: "Electron Standing waves on the Si(111)-√<3>×√<3>-Ag surface" Physical Review B. 59. 2035-2039 (1999)

N.Sato、T.Nagao、S.Takeda、S.Hasekawa：“Si(111)-√<3>×√<3>-Ag 表面上的电子驻波”物理评论 B. 59. 2035-2039 ( 1999）