Breakover-triggered dipole component having a controlled sensitivity

A dipole component formed in a semiconductor substrate of a first conductivity type and triggered by a breakover voltage, the dipole component comprising:

• a first vertical NPNP structure forming a main thyristor having a gate, a cathode and an anode;
• a second vertical NPNP structure forming a pilot thyristor having a gate, a cathode and an anode, the anode of the main thyristor and the anode of the pilot thyristor corresponding to a same layer on a lower surface of the semiconductor substrate;
• cathode metallization formed on the cathode of the main thyristor;
• connection metallization connecting the cathode of the pilot thyristor to the gate of the main thyristor;
• an additional region of the first conductivity type surrounded by the same layer, the additional region being disposed below a portion of the cathode of the pilot thyristor;
• and
• lower surface metallization formed on the lower surface of the semiconductor substrate and contacting the anodes of the main thyristor and the pilot thyristor and the additional region.

A dipole component, comprising:

• a first terminal and a second terminal;
• a main thyristor having a gate, a cathode, and an anode, the cathode of the main thyristor being coupled to the first terminal and the anode of the main thyristor being coupled to the second terminal;
• a pilot thyristor having a gate, a cathode and an anode, the cathode of the pilot thyristor being coupled to the gate of the main thyristor, and the anode of the pilot thyristor being coupled to the anode of the main thyristor;
• and
• a triggering transistor having a first terminal that is coupled to the anode of the pilot thyristor, a second terminal that is coupled to the cathode of the pilot thyristor, and having a control terminal that is coupled to the gate of the pilot thyristor.

A dipole component formed in a semiconductor substrate, the semiconductor substrate having a first type of conductivity and upper and lower surfaces, the dipole component comprising:

• first and second regions having a second type of conductivity formed in the upper surface of the semiconductor substrate, the second type of conductivity being opposite to the first type of conductivity, the first and second regions forming gate regions of a main thyristor and a pilot thyristor, respectively;
• third and fourth regions formed respectively in the first and second regions, the third and fourth regions having the first type of conductivity and forming cathode regions of the main thyristor and the pilot thyristor, respectively;
• first metallization formed on the upper surface of the semiconductor substrate in the third region that forms a first terminal of the dipole component;
• second metallization formed on the upper surface of the semiconductor substrate in the fourth and first regions that connects the cathode region of the pilot thyristor to the gate region of the main thyristor;
• a fifth region having the second type of conductivity formed in the lower surface of the semiconductor substrate below the third and fourth regions, the fifth region forming a common anode region that includes anode regions of the main thyristor and the pilot thyristor;
• a sixth region having the first type of conductivity formed in the lower surface of the semiconductor substrate below a portion of the fourth region and surrounded by the fifth region;
• and
• third metallization formed on the lower surface of the semiconductor substrate that connects the anode regions of the main thyristor and the pilot thyristor to the sixth region and forms a second terminal of the dipole component.

A method of forming a dipole component in a semiconductor substrate having a first type of conductivity, the method comprising the steps of:

• forming first and second regions having a second type of conductivity in an upper surface of the semiconductor substrate, the second type of conductivity being opposite to the first type of conductivity, the first and second regions respectively providing gate regions of a main thyristor and a pilot thyristor of the dipole component;
• forming third and fourth regions having the first type of conductivity in the first and second regions, the third and fourth regions providing cathode regions of the main thyristor and the pilot thyristor, respectively;
• coating the upper surface of the semiconductor substrate in the third region with metallization to provide a first terminal of the dipole component;
• coating the upper surface of the semiconductor substrate in the fourth and first regions with metallization to connect the cathode region of the pilot thyristor to the gate region of the main thyristor;
• forming a fifth region having the second type of conductivity in a lower surface of the semiconductor substrate below the third and fourth regions, the fifth region providing a common anode region that includes anode regions of the main thyristor and the pilot thyristor;
• forming a sixth region having the first type of conductivity in the lower surface of the semiconductor substrate below a portion of the fourth region, the sixth region being laterally surrounded by the fifth region;
• and
• coating the lower surface of the semiconductor substrate with metallization to connect the anode regions of the main thyristor and the pilot thyristor to the sixth region to provide a second terminal of the dipole component.