Effect of Deposition Temperature on Chemical Structure of Lanthanum Oxide/Si Interface Structure

Abstract

The effect of substrate-temperature during the deposition of lanthanum oxide on the chemical structure of lanthanum oxide/Si(100) interfacial transition layer formed between lanthanum oxide and Si-substrate was studied from the measurements of angle-resolved Si 1s, O 1s and La 3d 5/2 photoelectron spectra. In the case of the deposition at room temperature the amount of lanthanum silicate (La-silicate) was extremely small, and was not affected by the post deposition annealing (PDA) at 300°C, and increased by PDA at temperature above 500°C. On the other hand, in the case of the deposition at 300°C the amount of La-silicate increased appreciably by PDA even at 300°C. Therefore, the existence of La-silicate accelerates the formation of La-silicate by PDA.

Silicate Reaction Control at Lanthanum Oxide and Silicon Interface for Equivalent Oxide Thickness of 0.5 nm: Adjustment of Amount of Residual Oxygen Atoms in Metal Layer

“…On the other hand, the increase in the number of La-O-Si bonds with the thickness of the W film indicates that silicate reaction could be controlled by changing the thickness of the W film. 23,24) The windows of the hysteresis in the C-V curves for TiN (40 nm)/W (6 or 12 nm)/ La 2 O 3 (3.5 nm)/n-Si and W (60 nm)/La 2 O 3 (3.5 nm)/n-Si gate stack capacitors annealed for 2 s are summarized in Fig. 7.…”

(Invited) Study on Chemical Bonding States of High-k Gate Stacks for Advanced CMOS

“…Hard X-ray excited ARXPS study on LaOx/Si structure with and without post deposition annealing (14) The 3-nm-thick lanthanum oxide films were deposited on the hydrogen-terminated Si(100) surfaces maintained at room temperature by electron beam bombardment of lanthanum oxide (Samples A). Samples B, C and D were prepared by PDA of sample A in nitrogen gas under atmospheric pressure at 300°C, 500°C and 700°C, respectively.…”

“…Si 2s, O 1s, Sc 2p 3/2 , La 3d 5/2 , and Ce 3d 3/2 spectra photoelectron spectra were measured at photoelectron take-off angle(θ) of the angle within the range from 8 to 90 degrees with photoelectron acceptance angle of 3.3° at the entrance of electron energy analyzer using ESCA-300 manufactured by Scienta Instruments AB (15). Hard X-ray excited ARXPS study on LaOx/Si structure with and without post deposition annealing (14) The 3-nm-thick lanthanum oxide films were deposited on the hydrogen-terminated Si(100) surfaces maintained at room temperature by electron beam bombardment of lanthanum oxide (Samples A). Samples B, C and D were prepared by PDA of sample A in nitrogen gas under atmospheric pressure at 300°C, 500°C and 700°C, respectively.…”

“…The first topic is the influence of post deposition annealing (abbreviated as PDA hereafter) on the compositional depth profiles and chemical bonding states of interfacial transition layers of laminating structure (LaOx/Si, ScOx/Si, LaOx/ScOx/Si, ScOx/LaOx/Si, CeOx/LaOx, and LaOx/CeOx) by ARXPS (11,13). The second topic is Hard X-ray(hν = 8 keV) excited ARXPS study on LaOx/Si structure with and without PDA (14).…”