The silicon oxyhydrogen (Si-OH) bonds were found in large amounts in conventional Liquid-phase-deposited silicon dioxide using silica powder or gel as a saturation reagent in hydrofluorosilicic acid (H2SiF6). However, a more dense structure of LPD-SiO2 devoid of Si-OH bonds was found If the reagent is changed to silicic acid (SiO2:xH2O) and the concentration of H2SiF6 is kept above 2 M. At 30 degrees C, the water dilution of H2SiF6 from 2.5 to 1 M tends to enhance the deposition rate of silicon oxide and to introduce substantial amount of Si-OH bonds into the film when H2SiF6 concentration drops to below 1.5 M. This is attributed to the fact that water dilution tends to dilute the concentration of all components, but the decay of etching rate of SiO2 by HF is much faster than the growth rate of SiO2, because the removal of one silicon needs more HF molecules (from one to four HF) and the growth of one silicon needs only one intermediate species. The growth rate of silicon oxide decreases when H2SiF6 concentration is further lowered to 0.5 M. The delay time during. initial oxide growth follows the SiO2 growth rate, it is concluded that the delay time is the time that the solution needs to modify part of the Si-OH or Si-H bonds on the growth surface of SiO2 to Si-F bonds by hydrofluoric acid (HF).