Process for manufacturing buried channels and cavities in semiconductor material wafers

A process for manufacturing unfilled buried cavities in semiconductor material, comprising:

• forming a protective structure on a substrate of semiconductor material, the protective structure having an opening formed therein;
• forming a cavity in the substrate below the protective structure and in communication with the opening;
• and
• forming an epitaxial layer over the protective structure to cover the opening.

A process for manufacturing buried cavities and semiconductor wafers, comprising:

• forming an etching-aid region directly on a monocrystalline body of semiconductor material, the etching-aid region being formed of polycrystalline silicon;
• forming a nucleus region surrounded by a protective structure that covers the etching-aid region;
• forming a cavity in the monocrystalline body beneath the nucleus region;
• removing at least a top portion of the protective structure;
• and
• growing an epitaxial layer on the monocrystalline body and the nucleus region.

A process for manufacturing buried cavities in semiconductor material wafers, comprising:

• forming, on a monocrystalline body of semiconductor material, a nucleus region surrounded by a protective structure;
• forming a cavity in said monocrystalline body beneath said nucleus region;
• removing at least a top portion of said protective structure;
• and
• growing an epitaxial layer on said monocrystalline body and said nucleus region, comprising forming a monocrystalline region on the monocrystalline body and a polycrystalline region on the nucleus region.

A process for manufacturing buried cavities in semiconductor material, comprising:

• forming a protective structure on a substrate of semiconductor material, the protective structure having an opening formed therein, comprising forming on the substrate an etching-aid region and a layer stack, the etching-aid region comprising a polycrystalline silicon layer, and the layer stack comprising a first etch-shielding layer, a polycrystalline-silicon layer on the first etch-shielding layer, and a second etch-shielding layer on the polycrystalline-silicon layer;
• forming a cavity in the substrate below the protective structure and in communication with the opening;
• and
• forming an epitaxial layer over the protective structure to cover the opening.

A process for manufacturing buried cavities in semiconductor material, comprising:

• forming a protective structure on a substrate of semiconductor material, the protective structure having an opening formed therein, forming the protective structure for the comprising forming on the substrate an etching-aid region and a layer stack, the etching-aid region comprising a polycrystalline silicon layer, and the layer stack comprising a first etch-shielding layer, a polycrystalline-silicon layer on the first etch-shielding layer, and a second etch-shielding layer on the polycrystalline-silicon layer, and further forming a coating on the layer stack and on walls of the opening;
• forming a cavity in the substrate below the protective structure and in communication with the opening;
• and
• forming an epitaxial layer over the protective structure to cover the opening.