Growth of HfSiO_x films by Vapor–Liquid Hybrid Deposition Utilizing Si(OC₂H₅)₄/Hf(^tOC₄H₉)₄ Multilayer Adsorption

Abstract

In this study, a HfSiO x deposition technique is described that takes advantage of the multilayer adsorption of Si(OC2H5)4 (TEOS) and Hf( t OC4H9)4 (HTB), followed by the hydrolysis of all of the layers in liquid water. A thickness distribution better than ±3% and a uniform Si:Hf ratio over the 4-in. wafer were achieved using this deposition technique. The n-type metal–insulator–semiconductor field-effect transistor (MISFET) incorporating the HfSiO x film exhibited well-behaved capacitance–voltage characteristics. The channel mobility of 81% compared well to the universal curve at an effective field of 0.8 MV cm-1.

Initial surface reactions in atomic layer deposition of HfSixOy and HfO2: A comparative study by density functional theory

“…Especially, H 2 O as oxygen source has been used extensively in growing high-κ oxides, however, it is easy to induce interfacial SiO 2 -rich layer between silicon and high-κ oxides. Hence, tetraethoxy silane, Si(OC 2 H 5 ) 4 (TEOS), has recently been used as an oxygen source instead of H 2 O to avoid the formation of the SiO 2 interfacial layer [17][18][19]. It can be explained that the Si-O bonds are strong in alkoxides, silicon alkoxides would be less oxidizing toward silicon than H 2 O, H 2 O 2 , or O 3 and thus can depress the formation of the low-κ interfacial oxide layer.…”