Development of an Automated Vapor/Liquid Hybrid Deposition System to Form High-kDielectrics

Abstract

Vapor/liquid hybrid deposition (VALID) is a modified atomic layer deposition (ALD) method that combines adsorption of metal precursors from the vapor phase with their hydrolysis from the liquid phase. This paper is a report of the development of an automated VALID apparatus that performs the adsorption/hydrolysis processes with a reasonable throughput. HfO 2 films have been successfully produced with this automated system using Hf(O t C 4 H 9 ) 4 [hafnium tetra-tert-butoxide (HTB)]as the precursor. A brief discussion is given on the contribution of multilayer adsorption of HTB to the observed deposition rates.

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

“…This suggests that HTB covers the TEOS adsorbed surface and that the surface becomes hydrophilic when the HTB pressure is higher than 1 Pa. This observation is consistent with our previous results that multilayer adsorption of HTB on HfO 2 takes place when the HTB pressure is higher than 1 Pa. 3) The thickness uniformity of deposited HfSiO x films was significantly improved using TEOS/HTB multilayer adsorption, as illustrated in Fig. 3(b).…”

“…2) Recently, an automated VALID apparatus was developed that features a mobile wafer stage and dual heads for the adsorption and hydrolysis processes. 3) However, preparation of the HfSiO x film using this apparatus exhibited one problem. When TEOS was adsorbed on HfO x , the surface became hydrophobic because the hydrolysis of TEOS is relatively slow even in liquid water.…”

“…wafers. 3) A single growth cycle for HfSiO x deposition consisted of a TEOS/HTB multilayer adsorption and a hydrolysis process using liquid water. In the TEOS/ HTB multilayer adsorption process, TEOS was first introduced to the chamber.…”