High temperature-induced crystallization in tantalum pentoxide layers and its influence on the electrical properties

Progress in Materials for Microelectronics and Further Challenges

“…Interfacial layer for films of good quality is SiO2-like layer [31]. In the case of nonreactive gate, the obtained MOS structure is metal/Ta2O5/SiO2/Si.…”

Structural and electrical properties of Zn doped Mn oxide thin films grown on p-Si substrates

“…The field-lowering coefficient, β RS is given by: β RS = (e 3 /4πε 0 ε dyn ) 0.5 , where ε 0 ε dyn is the dynamic permittivity of the insulating layer, which must obey the following condition: n 2 < ε dyn < ε ox , where ε ox is the high-frequency relative permittivity and n is the optical refractive index [41,42]. For evaluation of the calculation, it is possible to use the refractive index driven from ε dyn , i.e.…”

Stress-induced leakage currents of the RF sputtered Ta2O5 on N-implanted silicon

“…Our structural studies of both RF sputtered and thermally grown Ta 2 O 5 have shown that the interfacial layer is composed of ultrathin SiO 2 and a near interfacial region containing Taand Si-suboxides [12,13]. We have also reported that the dielectric and electrical characteristics of the Ta 2 O 5 /Si structures can be improved by annealing in O 2 or N 2 [14][15][16], and this is due to the better microstructure and stoichiometry of both the bulk Ta 2 O 5 and the interfacial layer including reduction of its thickness after annealing. Nevertheless the low dielectric constant of this interfacial layer compromises the benefits of Ta 2 O 5 as a high-k material and limits the minimal achievable equivalent oxide thickness.…”

“…A number of methods compatible with silicon technology are successfully developed for obtaining thin films Ta 2 O 5 [2][3][4][5][6][7][8][9]. During the formation of Ta 2 O 5 on Si, however, an interfacial SiO 2 -containing layer is inevitably formed at the Si substrate [9][10][11][12][13][14][15][16]. The growth of this layer is related with the known thermodynamical instability of the most high-k materials in direct contact with Si against formation of SiO 2 (Ta 2 O 5 is not an exception).…”

“…The precise description of the behavior of high-k dielectrics requires considering them as stacked high-k/interfacial layer structures. The thickness and the composition of thin interfacial lower-k layer depend strongly on the technological history of the system Ta 2 O 5 /Si (including all annealing steps), and consequently are a subject of a great debate and ongoing investigations [2,5,9,13,15,[17][18][19][20][21][22]. Our structural studies of both RF sputtered and thermally grown Ta 2 O 5 have shown that the interfacial layer is composed of ultrathin SiO 2 and a near interfacial region containing Taand Si-suboxides [12,13].…”