A method for manufacturing a support substrate comprising a charge-trapping layer for a semiconductor-on-insulator or piezoelectric-on-insulator structure for a radio-frequency application, includes: placing a base substrate comprising a layer of native silicon oxide in a deposition chamber; raising the temperature of the deposition chamber to a deposition temperature of the charge-trapping layer; introducing an oxidizing gas into the deposition chamber in order to preserve the layer of native silicon oxide during the temperature rise; venting the oxygen from the deposition chamber at the formation temperature of the charge-trapping layer; and-depositing, in the deposition chamber, the charge-trapping layer of polycrystalline silicon on the layer of native silicon oxide.

The present application provides a method of fabricating a conductive feature. The method of fabricating the conductive feature includes steps of depositing an insulative layer on a substrate, forming a trench in the insulative layer, performing a cyclic process comprising a sequence of a deposition step and a removal step to deposit a conductive material in the trench until the deposition step has been performed is equal to a first preset number of times and a number of the times the removal step has been performed is equal to a second preset number of times, and filling the trench with the conductive material after the cyclic process.