Observation of band bending of metal/high-k Si capacitor with high energy x-ray photoemission spectroscopy and its application to interface dipole measurement

被引：34

作者：

Kakushima, K. ^{[1
]}

Okamoto, K. ^{[1
]}

Tachi, K. ^{[1
]}

Song, J. ^{[1
]}

Sato, S. ^{[1
]}

Kawanago, T. ^{[1
]}

Tsutsui, K. ^{[1
]}

Sugii, N. ^{[1
]}

Ahmet, P. ^{[2
]}

Hattori, T. ^{[2
]}

Iwai, H. ^{[2
]}

机构：

[1] Tokyo Inst Technol, Interdisciplinary Grad Sch Sci & Engn, Midori Ku, Yokohama, Kanagawa 2268502, Japan

[2] Tokyo Inst Technol, Frontier Res Ctr, Midori Ku, Yokohama, Kanagawa 2268502, Japan

来源：

JOURNAL OF APPLIED PHYSICS | 2008年 / 104卷 / 10期

关键词：

binding energy; elemental semiconductors; hafnium compounds; high-k dielectric thin films; lanthanum compounds; MIS structures; MOS capacitors; silicon; silicon compounds; surface potential; tungsten; work function; X-ray photoelectron spectra;

D O I：

10.1063/1.3021461

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

Band bendings of Si substrates have been observed using hard x-ray photoemission spectroscopy. With a capability of collecting photoelectrons generated as deep as 40 nm, the binding energy shift in a core level caused by the potential profile at the surface of the substrate results in a spectrum broadening. The broadening is found to be significant when heavily doped substrates are used owing to its steep potential profile. The surface potential of the substrate can be obtained by deconvolution of the spectrum. This method has been applied to observe the band bending profile of metal-oxide-semiconductor capacitors with high-k gate dielectrics. By comparing the band bending profiles of heavily-doped n(+)- and p(+)-Si substrates, the interface dipoles presented at interfaces can be estimated. In the case of W gated La(2)O(3)/La-silicate capacitor, an interface dipole to shift the potential of -0.45 V has been estimated at La-silicate/Si interface, which effectively reduces the apparent work function of W. On the other hand, an interface dipole of 0.03-0.07 V has been found to exist at Hf-silicate/SiO(2) interface for W gated HfO(2)/Hf-silicate/SiO(2) capacitor.

引用

页数：5

共 23 条

[21] Physical and electrical characteristics of high-κ gate dielectric Hf(1-x)LaxOy [J].