Semiconductor power device with multiple drain structure and corresponding manufacturing process

摘要

Process for manufacturing a multi-drain power electronic device (30) integrated on a semiconductor substrate (100) of a first type of conductivity whereon a drain semiconductor layer (20) is formed, characterised in that it comprises the following steps:
- forming at least a first semiconductor epitaxial layer (21) of the first type of conductivity of a first value of resistivity (ρ1) forming the drain epitaxial layer (20) on the semiconductor substrate (100),
- forming in the first semiconductor layer (21) first sub-regions (51) of a second type of conductivity by means of a first selective implant step with a first implant dose (Φ1P),
- forming in the first semiconductor layer (21) second sub-regions (D1, D1a) of the first type of conductivity by means of a second implant step with a second implant dose (Φ1N),
- forming a surface semiconductor layer (23) wherein body regions (40) of the second type of conductivity are formed being aligned with the first sub-regions (51),
- carrying out a thermal diffusion process so that the first sub-regions (51) form a single electrically continuous column region (50) being aligned and in electric contact with the body regions (40).