Title :
Leakage current comparison between ultra-thin Ta2O5 films and conventional gate dielectrics
Author :
Lu, Qiang ; Park, Donggun ; Kalnitsky, Alexander ; Chang, Celene ; Cheng, Chia-Cheng ; Tay, Sing Pin ; King, Tsu-Jae ; Hu, Chenming
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., California Univ., Berkeley, CA, USA
Abstract :
Capacitors with ultra-thin (6.0-12.0 nm) CVD Ta/sub 2/O/sub 5/ film were fabricated on lightly doped Si substrates and their leakage current (I/sub g/-V/sub g/) and capacitance (C-V) characteristics were studied. For the first time, samples with stack equivalent oxide thickness around 2.0 nm were compared with ultra-thin silicon dioxide and silicon oxynitride. The Ta/sub 2/O/sub 5/ samples showed remarkably lower leakage current, which not only verified the advantages of ultra-thin Ta/sub 2/O/sub 5/ as dielectrics for high density DRAM´s, but also suggested the possibility of its application as the gate dielectric material in MOSFET´s.
Keywords :
CVD coatings; MOS capacitors; MOSFET; dielectric thin films; leakage currents; semiconductor-insulator boundaries; tantalum compounds; 6 to 12 nm; C-V characteristics; MOS capacitors; MOSFET gate dielectric; SiNO-Si; SiO/sub 2/-Si; Ta/sub 2/O/sub 5/-Si; capacitance characteristics; conventional gate dielectrics; high density DRAM dielectric; leakage current characteristics; leakage current comparison; lightly doped Si substrates; silicon oxynitride; stack equivalent oxide thickness; ultra-thin Ta/sub 2/O/sub 5/ films; Annealing; Capacitance; Capacitors; Dielectric materials; Dielectric substrates; Electrodes; Furnaces; Leakage current; Semiconductor films; Silicon compounds;
Journal_Title :
Electron Device Letters, IEEE
