Deposition, annealing and characterisation of high‐dielectric‐constant metal oxide films

Abstract

Flims of metal oxides, such as Ta2O5, Nb2O5, Al2O3, HfO2, ZrO2 and TiO2 have been fabricated by use of different precursor materials, deposition techniques and annealing techniques. Several analytical methods were applied to study the layers. New data of fundamental properties of these metal oxides are reported and related to practical features that are of importance in device design and manufacturing of advanced, highly integrated devices. This overview may facilitate the choice of an optimal combination of precursor material, deposition technique and corresponding annealing procedure for a specific application of these metal oxide films in microelectronics.

Chemical Vapor Deposition of TixSi1–xO2 Films: Precursor Chemistry Impacts Films Composition

“…[1±4] ZrO 2 , [4±8] HfO 2 , [4,9±11] Ta 2 O 5 , [12,13] and various perovskites (e.g., Ba x Sr 1±x TiO 3 ).…”

Etching of Nb2O5 Thin Films by NbCl5

“…NbCl 5 (Aldrich, 99.9%) and Nb(OEt) 5 (Inorgtech/SAFC Hitech) were held inside the reactor in open source boats at 90 8C and 100 8C, respectively, and pulsed with inert gas valving [28]. We generally use D 2 O in the QMS studies with organic metal precursors to better distinguish the reaction byproducts from species forming in fragmentation and recombination reactions in the QMS ionizator [34].…”

“…k ¼ 4 for SiO 2 ) with potential thin film applications in integrated storage capacitors in, e.g., dynamic random access memory (DRAM) devices, [2][3][4][5] conductivity-type sensors for gases such as oxygen, [6,7] water, [8] and ammonia, [9] optical waveguides in laser light sources, [10,11] corrosion-resistant coatings, [12] and electrochromic devices. [13,14] Nb 2 O 5 is also a frequently used constituent of multicomponent oxides and solid solutions such as LiNbO 3 , [15] (Nb 1Àx Ta x ) 2 O 5 , [16] BaTi 1þ2n Nb 4 O 13þ4n , [17] [18] and dopant in various oxides such as ZrO 2 , [19] SnO 2 , [20] (Zr 0.8 Sn 0.2 )TiO 4 , [21,22] Pb(Zr 0.52 Ti 0.48 )O 3 , [23,24] and ZrO 2 Á 3Y 2 O 3 .…”

“…[13,14] Nb 2 O 5 is also a frequently used constituent of multicomponent oxides and solid solutions such as LiNbO 3 , [15] (Nb 1Àx Ta x ) 2 O 5 , [16] BaTi 1þ2n Nb 4 O 13þ4n , [17] [18] and dopant in various oxides such as ZrO 2 , [19] SnO 2 , [20] (Zr 0.8 Sn 0.2 )TiO 4 , [21,22] Pb(Zr 0.52 Ti 0.48 )O 3 , [23,24] and ZrO 2 Á 3Y 2 O 3 . [25] Methods used for depositing Nb 2 O 5 thin films include, among others, sputtering, [4][5][6][7]10,11,13] sol-gel, [14] and various CVD methods, [3,5,12,15] like ALD. [2,26] ALD, previously known as atomic layer epitaxy (ALE), is an advanced CVD technique where the precursors are alternately pulsed into the reactor separated by purging with inert carrier gas.…”

“…[2,26] ALD, previously known as atomic layer epitaxy (ALE), is an advanced CVD technique where the precursors are alternately pulsed into the reactor separated by purging with inert carrier gas. [27][28][29] Nb 2 O 5 has been grown successfully by ALD mainly using the Nb(OEt) 5 /H 2 O process. [26] Attempts to use the NbCl 5 / H 2 O process failed, resulting in non-uniform films that also appeared substantially different from run to run.…”