Gadolinium scandate as an alternative gate dielectric in field effect transistors on conventional and strained silicon

Nano-laminate vs. direct deposition of high permittivity gadolinium scandate on silicon by high pressure sputtering

“…It remains with the same thickness after the FGAs, 9 so the ternary compound shows a good stability, at least up to 450 °C. Assuming a relative permittivity of 3.9 for this SiO x layer, then the relative permittivity obtained for the gadolinium scandate is around 24, which agrees with the permittivity of the bulk material [8]. On the other hand, the C HF in accumulation of the nano-laminate, shown in reported that Gd-rich Gd 2-x Sc x O 3 presents higher dielectric constant than the stoichiometric ternary oxide.…”

“…This material could also be applied on high mobility substrates for high frequency applications [6]. Its main advantages over HfO 2 are that GdScO 3 remains amorphous and stable up to 1000 °C in contact with Si [7], showing a relative permittivity of 20-30 [8]. HfO 2 presents a low crystallization temperature (around 500 °C) [9], so a mixture of this oxide with SiON is used to keep the dielectric amorphous.…”

Optimization of in situ plasma oxidation of metallic gadolinium thin films deposited by high pressure sputtering on silicon

“…4,5 Among them, GdScO 3 shows adequate properties: [6][7][8] a k value up to 20, 6 greater than its binary constituents: Sc 2 O 3 (k $ 13) 9 and Gd 2 O 3 (k $ 17), 10 a band gap larger than 5 eV. 11,12 Additionally, some reports show that the films, in contact with Si, remain amorphous up to 1000 C. 4 This work is focused on the study of the properties of Gd 2 O 3 , obtained by high pressure sputtering (HPS) together with in situ plasma oxidation.…”

“…This is the first step toward the combination with Sc to produce GdScO 3 . Several groups are researching the properties of high k materials deposited by different techniques: metal-organic chemical vapor deposition, 8 atomic layer deposition, 13 pulsed laser deposition, 4 electron beam evaporation, 6,7 reactive sputtering, 14 etc. Yet, except for our group, there is no information reported on HPS for these materials.…”

Advanced CMOS Gate Stack: Present Research Progress

“…Also, Gallium arsenide (GaAs) substrates for MOS transistors are being considered for their high electron channel mobility [53,77]. Meanwhile, Germanium has been introduced as channel material due to its high mobility for both electron and holes as compared to silicon [27,37,65,78]. It is found that for suitable future scaling, a dielectric with K over 40 is preferred.…”