MOCVD and ALD of High‐k Dielectric Oxides Using Alkoxide Precursors

Abstract

A number of high-permittivity (j) dielectric oxides are currently being investigated as alternatives to SiO 2 as the dielectric insulating layer in sub-0.1 lm CMOS technology. Metal-organic (MO)CVD and atomic layer deposition (ALD) are promising techniques for the deposition of these high-j dielectric oxides. In this paper it is shown how the use of "designed" metal alkoxide precursors, containing bidentate donor-functionalized alkoxide ligands, in MOCVD leads to a marked improvement in the physical properties of the MOCVD precursors and process parameters. However, the use of such ligands is not as beneficial in the ALD process, highlighting the very different requirements of MOCVD and ALD precursors.

Modeling precursor diffusion and reaction of atomic layer deposition in porous structures

“…A wide range of applications exists for ALD, e.g., high-j oxides for CMOS and DRAM technology, 8,9 solar cell manufacturing, 10 catalysts, 11 and others. [12][13][14][15][16][17] In order to improve the control of the deposition process, several models for ALD have been published in recent years.…”

Deposition of Lanthanum Zirconium Oxide High‐k Films by Liquid Injection ALD and MOCVD

“…A wide variety of Zr precursors have been investigated in MOCVD and ALD, including ZrCl 4 , [31,32] [Zr(OR) 4 ], [33] [Zr(thd) 4 ], [34] [Zr(NR 2 ) 4 ] (R = Me, Et), [35,36] [Zr(NO 3 ) 4 ]. [37] However, all have various problems associated with them (e.g., impurity incorporation, low reactivity, low thermal stability) and none have proved suitable for dual application in ALD and MOCVD.…”

Non‐Aqueous Routes to Metal Oxide Thin Films by Atomic Layer Deposition

“…[12,29] 2) Reactions of carboxylic acid compounds with metal oxide surfaces were extensively studied in ultrahigh vacuum. It is generally accepted that the carboxylic acids adsorb dissociatively.…”

“…[10,11] Taking a closer look at the chemistry, it is noticed that the evolution of ALD follows a development which is similar to that of sol-gel chemistry. In both cases, approaches were pursued to improve the metal oxide formation, either by modifying the precursor [12,13] or by using alternative nonhydrolytic reactions. [9,[14][15][16][17] Inspired by non-aqueous sol-gel routes for the formation of metal oxides in solution, we introduce herein a new approach for the ALD of metal oxide films.…”