Titre du document / Document title

Characteristics and mechanism of tunable work function gate electrodes using a bilayer metal structure on SiO₂ and HfO₂

Auteur(s) / Author(s)

LU Ching-Huang ⁽¹⁾ ; WONG Gloria M. T. ⁽¹⁾ ; DEAL Michael D. ⁽²⁾ ; TSAI Wilman ⁽³⁾ ; MAJHI Prashant ⁽⁴⁾ ; CHI ON CHUI ⁽⁴⁾ ; VISOKAY Mark R. ⁽⁵⁾ ; CHAMBERS James J. ⁽⁵⁾ ; COLOMBO Luigi ⁽⁵⁾ ; CLEMENS Bruce M. ⁽¹⁾ ; NISHI Yoshio ⁽⁶⁾ ;

Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)

⁽¹⁾ Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305, ETATS-UNIS
⁽²⁾ Department of Electrical Engineering, Stanford University, Stanford, CA 94305, ETATS-UNIS
⁽³⁾ Intel Corporation, Santa Clara, CA 95054, ETATS-UNIS
⁽⁴⁾ Sertatech Incorporated, Austin, TX 78741, ETATS-UNIS
⁽⁵⁾ Texas Instruments, Inc, Dallas, TX 75243, ETATS-UNIS
⁽⁶⁾ Department of Electrical Engineering and the Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305, ETATS-UNIS

Résumé / Abstract

In this letter, we investigate a method to adjust the gate work function of an MOS structure by stacking two metals with different work functions. This method can provide work function tunability of approximately 1 eV as the bottom metal layer thickness is increased from 0 to about 10 nm. This behavior is demonstrated with different metal combinations on both SiO₂ and HfO₂ gate dielectrics. We use capacitance-voltage (C-V) characteristics to investigate the effect of different annealing conditions and different metal/metal bilayer couples on the work function. By comparing the as-deposited and annealed films, and by comparing with metals that are relatively inert with each other, we deduce that the work function tuning behavior likely involves metal/metal interdiffusion.

Revue / Journal Title

IEEE electron device letters   ISSN 0741-3106   CODEN EDLEDZ 

Source / Source

2005, vol. 26, n^o7, pp. 445-447 [3 page(s) (article)] (15 ref.)

Langue / Language

Anglais

Editeur / Publisher

Institute of Electrical and Electronics Engineers, New York, NY, ETATS-UNIS  (1980) (Revue)

Mots-clés anglais / English Keywords

High k dielectric ; Interdiffusion ; Annealing ; Voltage capacity curve ; Capacitance ; MOS structure ; Bilayers ; Work function ;

Mots-clés français / French Keywords

Diélectrique permittivité élevée ; Diffusion mutuelle ; Recuit ; Caractéristique capacité tension ; Capacité électrique ; Structure MOS ; Bicouche ; Travail sortie ;

Mots-clés espagnols / Spanish Keywords

Dieléctrico alta constante dieléctrica ; Difusión mútua ; Recocido ; Característica capacidad tensión ; Capacitancia ; Estructura MOS ; Función de trabajo ;

Mots-clés d'auteur / Author Keywords

HfO2 ; high-K dielectrics ; metal gate ; SiO2 ; work function ;

Localisation / Location

INIST-CNRS, Cote INIST : 222 V, 35400013855433.0070