Effect of surface treatment of Si substrates and annealing condition on high-k rare earth oxide gate dielectrics

Atomic Layer Deposition of Gadolinium Oxide Films

“…[9,21] Using NiSi metal gates on Gd 2 O 3 grown on Si, it has been possible to achieve equivalent oxide thicknesses as low as 0.86 nm. [10] Gd 2 O 3 films can be grown by several techniques such as the sol-gel method, [2] electron beam evaporation (EBE), [4,6,9,13,14,17] sputtering, [12] ion-beam epitaxy, [5] molecular beam epitaxy (MBE), [10,19,21] oxidation of Gd metal films, [16,20,22] metal-organic (MO)CVD, [15,23] and ALD. [24][25][26] The growth techniques available may be distinguished on the basis of optimum deposition temperatures and suitability for large area substrate processing.…”

“…[9,13,14] In some cases of ultrathin (2.8-5.3 nm) film growth, the films were deposited at 250°C with an obligatory post-deposition long-term anneal at 400°C. [17] Analogous demand for high deposition temperatures and/or annealings applies to ion-beam deposited and MBE-grown films, as well as to sol-gel technology.…”

Characteristics of high dielectric cubic Gd2O3 thin films deposited on cubic LaAlO3 by pulsed laser deposition

“…The rare earth metal oxides have recently attracted much attention to replace silicon dioxide as the potential candidate materials for gate dielectric in the future CMOS devices because most of these oxides have many advantages such as medium dielectric constant, high-energy bandgap, and very good thermodynamic stability with respect to silicon [2]. In recent years, these amorphous materials with higher dielectric constants are topics of research worldwide [3][4][5][6][7][8]. For most of the high-k oxides, however, crystallization occurs during high-temperature post-deposition processing, leading to higher leakage current due to the formation of grain boundaries [9].…”

Characterisation of oxidised gadolinium film deposited on Si (100) substrate

“…They have high resistivity (ρ = 10 12 -10 15 cm), high relative permittivity (ε = [7][8][9][10][11][12][13][14][15][16][17][18][19][20] and large band gap (E g = 4-6 eV) [2]. Moreover, REOs are stable in contact with silicon at room temperature, but there is a possibility of formation of silicates during annealing at high temperatures (800-1000 • C) especially in oxygen or air atmosphere [3][4][5][6].…”

“…Most studies [6][7][8][9][10][11] were focused on pure REOs as insulators of a few-nanometres thickness for the production of a SiO 2 -alternative or concentrated on investigation of the composition of the interface layer formed between REOs films and Si substrates. Gadolinium oxide films grown on Si substrates were studied in several works [12][13][14][15][16]. They were prepared by different techniques, especially by electron-beam-gun (EBG) evaporation technique.…”