Title :
Electrical properties of high-k Ta2O5 gate dielectrics on strained Ge-rich layers
Author :
Chakraborty, S. ; Samanta, S.K. ; Bhattacharya, S. ; McCarthy, J. ; Armstrong, B.M. ; Gamble, H.S. ; Dalapati, G.K. ; Das, S. ; Perova, T.S. ; Moore, R.A. ; Maiti, C.K.
Author_Institution :
Dept. of Electron. & Electr. Commun. Eng., Indian Inst. of Technol., Kharagpur, India
Abstract :
Thin films of Ta2O5 have been deposited on strained Ge-rich layers using tantalum pentaethoxide [Ta(OC2H5)5] by plasma enhanced chemical vapor deposition (PECVD) at low temperature. Electrical properties of the deposited samples have been measured using high frequency capacitance-voltage (C-V), conductance-voltage (G-V), and current-voltage (I-V) techniques. The fixed oxide charge density (Qf/q) and interface state density (Dit) are found to be 1.04 × 1012 cm-2 and 3.09 × 1011 cm-2 eV-1, respectively. The leakage current is observed to be dominated by Schottky emission (SE) at low electric field. The stress induced leakage current (SILC) is found to be negligible, indicating the good reliability of the deposited thin films.
Keywords :
Ge-Si alloys; Schottky effect; carrier density; current density; dielectric thin films; electrical conductivity; interface states; leakage currents; plasma CVD coatings; semiconductor-insulator boundaries; tantalum compounds; Schottky emission; electrical properties; fixed oxide charge density; high frequency capacitance-voltage techniques; high frequency conductance-voltage techniques; high frequency current-voltage techniques; high-k Ta2O5 gate dielectrics; interface state density; leakage current; plasma enhanced chemical vapor deposition; strained Ge-rich layers; stress induced leakage current; tantalum pentaethoxide; Capacitance-voltage characteristics; High K dielectric materials; High-K gate dielectrics; Leakage current; Plasma chemistry; Plasma density; Plasma measurements; Plasma properties; Plasma temperature; Sputtering;
Conference_Titel :
Microelectronics, 2004. 24th International Conference on
Print_ISBN :
0-7803-8166-1
DOI :
10.1109/ICMEL.2004.1314868
