Interface and electrical properties of Tm₂O₃ gate dielectrics for gate oxide scaling in MOS devices

Atomic-layer deposited thulium oxide as a passivation layer on germanium

“…6 Another approach to achieving sub-nm EOT Ge gate stacks is utilizing Al 2 O 3 barrier IL properties. 2,3,7 Rare-earth thulium oxide (Tm 2 O 3 ) has been considered as the main high-k dielectric 8 and as a capping layer for La 2 O 3based gate stacks, 9 but only on Si. A low reactivity of Tm 2 O 3 with the Si substrate has been observed.…”

Improved low-frequency noise for 0.3nm EOT thulium silicate interfacial layer

“…This work is different from benchmark studies where HfO, ZrO and ALO and layered combination of these have been used as gate materials [11] [12]. Few studies have been reported on intergration of Tm 2 O 3 as high-k dielectrics in MOS devices [7] and as capping layer for La 2 O 3 gate stacks [13]. No studies have been published on 1/f noise of Tm 2 O 3 yet, to the best of the author's knowledge.…”

Solution-Processed Rare-Earth Oxide Thin Films for Alternative Gate Dielectric Application

“…Among diverse RE materials, the most stable compounds are RE oxides (REOs), in which most of the RE elements hold typically a trivalent state with the general formula of sesquioxide, Ln 2 O 3 (e.g., Sc 2 O 3 , Y 2 O 3 , La 2 O 3 , Sm 2 O 3 , and Er 2 O 3 ), while for Ce, Pr, and Tb, more stable oxides exist as CeO 2 , Pr 6 O 11 , and Tb 4 O 7 , respectively . The applications of REOs have now been broadened to luminescent, optical, and dielectric materials. − Previous studies on REOs revealed that they possess remarkable electrical properties, such as high relative dielectric constant, large areal capacitance, superior electrical breakdown strength, high transparency, and superior thermal stability which fulfill the requirements of dielectrics in electronics, especially thin-film transistors (TFTs). ,− Except for Pm 2 O 3 due to its radioactive property, all the other 16 REOs films have been studied and employed as gate dielectrics in recent years, and the results revealed that the REOs are promising candidates as alternative gate dielectrics to traditional SiO 2 . − Therefore, REOs, together with other potential oxides (e.g., Al 2 O 3 , ZrO 2 , and HfO 2 ), have also been considered as solutions to the problems of large leakage current, high standby power consumption, and inferior gate dielectric reliability for continued downscaling of electronics. − Usually, these oxides were prepared by some traditional costly vacuum-based techniques, such as physical vapor deposition (PVD), chemical vapor deposition (CVD), and atomic layer deposition (ALD), which are expensive and time-consuming. ,,− In this regard, solution-processable dielectrics are more favorable in electronics as they are cost-effective and can be manufactured in large amounts. − Sol–gel method is a well-known and popular technique as it offers the possibility of tuning properties of resulting products by adjusting the precursor solutions easily. It has been empolyed in numerous fields including the preparation of high performance dielectrics.…”