Asymmetrical bidirectional protection component
AssigneeSTMicroelectronics (Tours) SAS
InventorBenjamin Morillon
Life of this patent
Estimating the term…
Abstract
An asymmetrical bidirectional protection component formed in a semiconductor substrate of a first conductivity type, including: a first implanted area of the first conductivity type; a first epitaxial layer of the second conductivity type on the substrate and the first implanted area; a second epitaxial layer of the second conductivity type on the first epitaxial layer, the second layer having a doping level different from that of the first layer; a second area of the first conductivity type on the outer surface of the epitaxial layer, opposite to the first area; a first metallization covering the entire lower surface of the substrate; and a second metallization covering the second area.
Claims25
An asymmetrical bidirectional protection component formed in a semiconductor substrate of a first conductivity type, comprising:
- a first implanted area of the first conductivity type;
- a first epitaxial layer of a second conductivity type on the substrate and the first implanted area;
- a second epitaxial layer of the second conductivity type on the first epitaxial layer, the second epitaxial layer having a doping level different from that of the first epitaxial layer;
- a second implanted area of the first conductivity type on the outer surface of the second epitaxial layer, opposite to the first implanted area, wherein dopant concentrations of the first and second implanted areas are higher than dopant concentrations of the first and second epitaxial layers;
- a first metallization covering the entire lower surface of the substrate;
- and
- a second metallization covering the second implanted area.
An asymmetrical bidirectional protection component comprising:
- a semiconductor substrate of a first conductivity type;
- a first implanted region of the first conductivity type within the semiconductor substrate;
- a first layer of a second conductivity type adjacent the substrate and the first implanted region;
- a second layer of the second conductivity type adjacent the first layer, the second layer having a doping level different from that of the first layer;
- a second implanted region of the first conductivity type at an outer surface of the second layer, wherein dopant concentrations of the first and second implanted regions are higher than dopant concentrations of the first and second layers;
- and
- an electrically insulating trench extending through the first and second layers from the outer surface of the second layer.
A method of manufacturing an asymmetrical bidirectional protection component in a semiconductor substrate of a first conductivity type, comprising:
- implanting a dopant of the first conductivity type in a first area;
- forming by epitaxy a first layer of the second conductivity type on the substrate and the first implanted area;
- forming by epitaxy a second layer of the second conductivity type on the first layer, the second layer having a doping level different from that of the first layer;
- implanting a dopant of the first conductivity type in a second area on the outer surface of the second layer, opposite to the first area;
- doping the first area and the second area to a concentration that is higher than a concentration of the first layer and a concentration of the second layer;
- covering the entire lower surface of the substrate with a first metallization;
- and
- covering the second area with a second metallization.
Dependencies are inferred from the claim text.