High Growth Rate of Erbium Oxide Thin Films in Atomic Layer Deposition from (CpMe)3Er and Water Precursors

Abstract

Organometallic tris(methylcyclopentadienyl)erbium and water were successfully exploited as precursors for the atomic layer deposition (ALD) of Er 2 O 3 thin films. Deposition studies were carried out in the temperature range 175±450 C, where Si(100) and soda-lime glass were used as substrates. ALD-type growth mechanism could be verified at relatively low deposition temperatures of 250 C and 300 C, where a high growth rate (1.5 per cycle) for an ALD process was obtained. The deposited Er 2 O 3 films were smooth and very uniform, and contained only low concentrations of carbon and hydrogen as impurities. The films were crystalline with the (111) orientation of the cubic phase dominating. The effective permittivity of the Er 2 O 3 /native SiO 2 insulator stack was approximately 10.

Rare-earth oxide thin films for gate dielectrics in microelectronics

“…The list of ALD rare-earth oxide processes (Table 3) [34,81,[85][86][87][88][89][90][91][92][93][94][95][96][97][98][99][100][101][102][103] already covers all the rare-earth elements [104]. The oxygen precursor most common in ALD processes, H 2 O, does not show chemical activity sufficient for the reaction with ␤-diketonates and films could thus not be obtained using water as the precursor.…”

Er3+ and Si luminescence of atomic layer deposited Er-doped Al2O3 thin films on Si(100)

“…Using the same Er-precursor, Päiväsaari et al reported a higher GPC while using significantly shorter dosing times. 25 These shorter dosing times can probably be related to the use of an open crucible rather than a bubbler system as used in this work. The precursor in the bubbler has a comparatively smaller surface area, and, therefore, the influence of the low precursor vapor pressure is more pronounced.…”

“…Päiväsaari et al reported an ALD process for Er 2 O 3 , using Er(thd) 3 and Er(CpMe) 3 as precursors, in combination with O 3 and H 2 O as oxidants, respectively. 24,25 Al 2 O 3 :Er waveguides have also been synthesized by ALD, 26 but no details on the ALD process were given. In addition, ALD has been used for Er incorporation in Y 2 O 3 by alternating the growth of Y 2 O 3 and Er 2 O 3 layers.…”

Structural and optical properties of lanthanide oxides grown by atomic layer deposition (Ln = Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb)

“…Among the lanthanide oxides and precursors studied in this work, Nd 9 and Er 10 have previously 30 been investigated in the temperature range 200 -450 °C, Yb 11 at 250 -400 °C, while for Sm, Eu, Dy, Ho, Tm 8 , and Tb 12 only data at 300 °C are available. The use of alternative precursors has been investigated [13][14][15][16][17][18][19][20] . Ternary oxides and nanolaminates containing lanthanides have been deposited both by using the β- 35 diketonate chelates Ln(thd) 3 (Hthd = 2,2,6,6-tetramethyl-3,5-heptanedione) 9,12,[21][22][23][24][25][26] and alternative [27][28][29] precursors.…”