Capacitance-Voltage Analysis of ZrO₂ Thin Films Deposited by Thermal MOCVD Technique

Abstract

The capacitance-voltage (C-V) characteristics of thin films of ZrO2 deposited by thermal metal-organic chemical vapour deposition (MOCVD) have been analyzed. The films were grown at three different temperatures (500, 550 and 600 ºC) and 1 mbar pressure from a novel monomeric zirconium amide-guanidinate complex [Zr(NEtMe)2(guanidinate)2]. The true capacitance was determined from measurements made at different frequencies in order to account for the series and shunt parasitic resistances during C-V measurements. Films grown at 500 and 550 ºC showed no hysteresis while those grown at 600 ºC exhibited a very small hysteresis window ≈0.16 V for O2 flow of 100 sccm and ≈0.19 V for 50 sccm O2 flow. A very small voltage shift is also obtained for the device under 10 hr voltage stress. These preliminary in-depth electrical results suggest that quality ZrO2 can be grown from the novel [Zr(NEtMe)2(guanidinate)2] complex precursor paving the way for their use as future gate dielectrics.

Research Progress of High Dielectric Constant Zirconia-Based Materials for Gate Dielectric Application

“…Up to now, many deposition processes have been applied to the preparation of Zr-based high-k gate dielectrics, such as atomic layer deposition (ALD) [17], sol-gel process [18], chemical vapor deposition (CVD) [19], sputtering [20], molecular beam epitaxy (MBE) [21], electron beam evaporation (EBE) [22], pulsed laser deposition (PLD) [23] and so on. The following focused on several main preparation methods.…”

“…The chemical reactions of precursor species occur both in the gas phase and on the substrate [33]. Reactions can be promoted or initiated by heat (thermal CVD) [19], higher frequency radiation such as UV (photo-assisted CVD) [34] or a plasma (plasma-enhanced CVD) [35]. Moreover, it has capability to mass produce components that are uniformly coated with complex shapes and deposited with good conformal coverage.…”

Development of Volatile Inorganic Compounds and Their Application for Chemical Vapour Deposition of Metal and Metal Oxide Thin Films

“…Gadolium nitride and dysprosium nitride films were deposited by CVD using tris(N,N'-diisopropyl-2-dimethylamidoguanidinato)Ln(III) (Ln = Gd, Dy) as single source precursors and also with the aid of ammonia as a co-reagent . [11] Oxygen has also been used as a co-reagent to deposit ZrO2, [12] TiO2, [13] HfO2, [14,15] oxides of some lanthanide metals, [11,16,17] as well as lanthanide-doped metal oxide films. [1] A dimeric copper (I) guanidinate, [(N,N'-diisopropyl-2-dimethylamido-guanidinato)copper(I)]2, has been used to deposit copper metal nanoparticles onto flat substrates [18] and optical fibers.…”

“…Al-back contact c-Si Zr(NEtMe)2(guan)2 O2 500 -600 8.74 NR 2009 [12] ZrO2 Glass Zr(CpMe)(η 1 -guan)2Cl Air 500 -600 NR 5-18% 2009 [32] In2O3 Si (100) Glass In(guan)3 Air 275 - 350 43 In(0): < 2% 2011 [4] HfO2…”

“…The decay of the methyl peak was monitored as a ratio against tetramethylsilane (TMS) within the solution and was shown to be a first order decomposition. From these studies it was clear that nbip (9), iso-bip (10), and tbip (12) were the most stable complexes with half-lives of 24.8, 9.00, and 10.3 days, respectively.…”