Effects of Postdeposition Annealing in Argon Ambient on Metallorganic Decomposed CeO[sub 2] Gate Spin Coated on Silicon

Abstract

Cerium oxide (CeO2) solution was prepared by cerium(III) acetylacetonate hydrate, methanol, and acetic acid as the starting materials via the metallorganic decomposition (MOD) method. Postdeposition annealing was performed onto the MOD-derived CeO2 films deposited onto n-type Si substrates at different temperatures (600, 800, and 1000°C ) under the flow of argon gas. A slow cooling rate was then accomplished for samples to cool down to room temperature. Four orientations [(111), (200), (220), and (311)] of CeO2 films were revealed by X-ray diffraction analysis as well as α-Ce2normalO3 and cerium silicate (Ce2Si2normalO7) . Epitaxial-like behavior was shown in the sample annealed at 600°C due to the (200)-oriented CeO2 film, and the dominance of this plane ceased with the increase in annealing temperature. A negative voltage shift was observed in all of the samples, indicating that positive oxide charges were trapped in the oxide as a result of the presence of oxygen vacancies. An interface trap density was extracted from the capacitance–voltage measurement, and it was related to the current density–voltage characteristics of the investigated samples. The lowest density was perceived by the sample annealed at 1000°C due to the increment in the Ce2Si2normalO7 layer, reduction in total interface trap density, and effective oxide charge.

Effects of post-deposition annealing temperature and time on physical properties of metal-organic decomposed lanthanum cerium oxide thin film

“…These peaks are similar to that of pure CeO 2 because La x Ce y O z is the solid solution of La 2 O 3 in CeO 2 with fluorite type [35]. The XRD patterns of MOD-derived CeO 2 films on Si substrate [22] are included in Fig. 1 (200), (220), (311), and (222) planes.…”

“…REOs are attractive because there is a compromise between the energy gap and k, so as to combine good insulating properties with potential for oxide scaling. La 2 O 3 [12][13][14][15], Y 2 O 3 [16][17][18][19], and CeO 2 [20][21][22] are the examples of REO, which have been deposited on Si substrate.…”

Growth and electrical properties of AlOx grown by mist chemical vapor deposition

“…[1][2][3][4][5] The physical properties of each material (which have been reported with bulk materials or in other reviews) are summarized in Table I. [5][6][7][8] There have been many reports concerning the thermal stability of such materials, since it is very important for device fabrication.…”

“…18,21 With MOCVD and thin films can be grown although the deposition rate is too low (< 1 nm/min). On the other hand, spray and sol-gel are growth techniques using a highly stable source solute and low-vapor-pressure materials, such as aluminum chloride (AlCl 3 ) and aluminum acetylacetonate (Al(acac) 3 ). In these methods, the thin films are grown by thermal decomposition of source materials which are dissolved in solvents.…”

“…Aluminum oxide (AlO x ) thin films were grown using aluminum acetylacetonate (Al(acac) 3 ) as a source solute by mist chemical vapor deposition (mist CVD). The AlO x thin films grown at temperatures above 400…”