Abstract: A method for fabricating a silicon oxide and silicon glass layers at low temperature using High Density Plasma CVD with silane or organic or inorganic silane derivatives as a source of silicon, inorganic compounds containing boron, phosphorus, and fluorine as doping compounds, oxygen, and gas additives is described. RF plasma with certain plasma density is maintained throughout the entire deposition step in a reactor chamber. A key feature of the invention's process is a mole ratio of gas additive to source of silicon, which is maintained in the range of about 0.3-20 depending on the compound used and the deposition process conditions. As a gas additive, one of the group including halide-containing organic compounds having the general formula CxHyRz, and chemical compounds with the double carbon-carbon bonds having the general formula CnH2n, is used.