Charge transport across metal/molecular (alkyl) monolayer-Si junctions is dominated by the LUMO level

被引：50

作者：

Yaffe, Omer ^{[1
]}

Qi, Yabing ^{[2
]}

Scheres, Luc ^{[3
]}

Puniredd, Sreenivasa Reddy ^{[4
]}

Segev, Lior ^{[1
]}

Ely, Tal ^{[1
]}

Haick, Hossam ^{[4
]}

Zuilhof, Han ^{[3
]}

Vilan, Ayelet ^{[1
]}

Kronik, Leeor ^{[1
]}

Kahn, Antoine ^{[2
]}

Cahen, David ^{[1
]}

机构：

[1] Weizmann Inst Sci, Dept Mat & Interfaces, IL-76100 Rehovot, Israel

[2] Princeton Univ, Dept Elect Engn, Princeton, NJ 08544 USA

[3] Wageningen Univ, Lab Organ Chem, NL-6703 HB Wageningen, Netherlands

[4] Technion Israel Inst Technol, Dept Chem Engn, IL-32000 Haifa, Israel

来源：

PHYSICAL REVIEW B | 2012年 / 85卷 / 04期

基金：

美国国家科学基金会; 以色列科学基金会;

关键词：

SELF-ASSEMBLED MONOLAYERS; ALKANETHIOL MONOLAYER; ELECTRONIC TRANSPORT; CHAIN MONOLAYERS; MOLECULE; PHOTOEMISSION; CONDUCTANCE; BARRIER; SILICON; GAAS;

D O I：

10.1103/PhysRevB.85.045433

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We compare the charge transport characteristics of heavy-doped p(++)- and n(++)-Si-alkyl chain/Hg junctions. Based on negative differential resistance in an analogous semiconductor-inorganic insulator/metal junction we suggest that for both p(++)- and n(++)-type junctions, the energy difference between the Fermi level and lowest unoccupied molecular orbital (LUMO), i.e., electron tunneling, controls charge transport. This conclusion is supported by results from photoelectron spectroscopy (ultraviolet photoemission spectroscopy, inverse photoelectron spectroscopy, and x-ray photoemission spectroscopy) for the molecule-Si band alignment at equilibrium, which clearly indicate that the energy difference between the Fermi level and the LUMO is much smaller than that between the Fermi level and the highest occupied molecular orbital (HOMO). Furthermore, the experimentally determined Fermi level - LUMO energy difference, agrees with the non-resonant tunneling barrier height, deduced from the exponential length attenuation of the current.

引用

页数：8

共 68 条

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