Ab Initio Modeling of Schottky-Barrier Height Tuning by Yttrium at Nickel Silicide/Silicon Interface

Author

Geng, Li ; Magyari-Kope, Blanka ; Zhang, Zhiyong ; Nishi, Yoshio

Author_Institution

Dept. of Microelectron., Xi´´an Jiaotong Univ., Xian

Volume

29

Issue

7

fYear

2008

fDate

7/1/2008 12:00:00 AM

Firstpage

746

Lastpage

749

Abstract

The mechanism of Schottky-barrier height (SBH) tuning by yttrium (Y) segregated at nickel silicide (NiSi₂)/silicon interface is investigated based on first-principle calculations. SBH modification can be explained by a new chemical structure that forms when Y atoms substitute silicon atoms near the interface. Silicon dangling bonds are saturated, leading to a new pinning-free interfacial structure. When other layers of Y atoms are segregated in , SBH for electrons can be reduced from 0.65 to 0.1 eV. The previously reported experimental phenomena can be explained by the calculations.

Keywords

Schottky barriers; ab initio calculations; chemical structure; dangling bonds; elemental semiconductors; interface structure; nickel compounds; semiconductor-insulator boundaries; silicon; yttrium; NiSi₂-Y-Si; Schottky-barrier height; ab initio modeling; chemical structure; first-principle calculations; nickel silicide-silicon interface; pinning-free interfacial structure; silicon dangling bonds; yttrium; Atomic layer deposition; Chemicals; Conductivity; Electrons; Nanoscale devices; Nickel; Schottky barriers; Silicides; Silicon; Yttrium; Nickel silicide $(hbox{NiSi}_{2})$; Schottky barrier (SB) modulation; segregation; yttrium (Y);

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2008.2000647

Filename

4558097