Support substrate made of silicon suitable for radiofrequency applications and associated manufacturing method

A method for manufacturing a support substrate, the method comprising the following steps:

• a) providing a base substrate made of monocrystalline silicon comprising P-type dopants and having a resistivity that is greater than or equal to 250 ohm·cm and strictly less than 500 ohm·cm, and a content of interstitial oxygen between 13 ppma and 19 ppma;
• b) epitaxially growing a layer made of monocrystalline silicon on the base substrate, to form an epitaxial layer made of monocrystalline silicon comprising P-type dopants, the epitaxial layer having a thickness between 2 microns and 30 microns, at least an upper portion of the epitaxial layer having a resistivity greater than or equal to 3000 ohm·cm;
• and
• c) depositing a charge-trapping layer on the epitaxial layer, the charge-trapping layer made of polycrystalline silicon, the charge-trapping layer having a resistivity greater than or equal to 1000 ohm·cm and a thickness between 1 micron and 10 microns.