Title :
Current transport in metal/hafnium oxide/silicon structure
Author :
Zhu, W.J. ; Ma, Tso-Ping ; Tamagawa, Takashi ; Kim, J. ; Di, Y.
Author_Institution :
Yale Univ., New Haven, CT, USA
Abstract :
Based on the experimental results of the temperature dependence of gate leakage current and Fowler-Nordheim tunneling characteristics at 77 K, we have extracted the energy band diagrams and current transport mechanisms for metal/HfO/sub 2//Si structures. In particular, we have obtained the following quantities that will be useful for modeling and simulation: i) HfO/sub 2//Si conduction band offset (or barrier height): 1.13 /spl plusmn/ 0.13 eV; ii) Pt/HfO/sub 2/ barrier height: /spl sim/ 2.48 eV; iii) Al/HfO/sub 2/ barrier height: /spl sim/ 1.28 eV; iv) electron effective mass in HfO/sub 2/: 0.1 m/sub o/, where m/sub o/ is the free electron mass and v) a trap level at 1.5 /spl plusmn/ 0.1 eV below the HfO/sub 2/ conduction band which contributes to Frenkel-Poole conduction.
Keywords :
MIS structures; MOS capacitors; Poole-Frenkel effect; conduction bands; effective mass; hafnium compounds; impact ionisation; leakage currents; silicon; tunnelling; 77 K; Fowler-Nordheim tunneling; Frenkel-Poole conduction; HfO/sub 2/-Si; MOS capacitors; Schottky emission; barrier height; conduction band offset; current transport; electron effective mass; energy band diagrams; gate leakage current; high-k dielectrics; leakage current; modeling; simulation; temperature dependence; trap level; Effective mass; Electrons; Hafnium oxide; High-K gate dielectrics; Leakage current; Semiconductor films; Silicon; Substrates; Temperature dependence; Tunneling;
Journal_Title :
Electron Device Letters, IEEE
