ESD protection device
AssigneeInfineon Technologies AG
InventorsChristian Cornelius Russ, Gabriel-Dumitru Cretu, Filippo Magrini, Markus Eckinger, Chi Dong Nguyen
Life of this patent
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Abstract
A silicon controlled rectifier (SCR) includes a first p-well region, a second p-well region, and an n-doped region. The first p-well region is coupled to a first trigger terminal via a first p-doped tap region disposed in the first p-well region. The first p-doped tap region has a higher concentration of a p-type dopant than the first p-well region. The second p-well region is coupled to a second trigger terminal via a second p-doped tap region disposed in the second p-well region. The second p-doped tap region has a higher concentration of a p-type dopant than the second p-well region.
Claims27
A semiconductor device comprising:
- a first p-well region and a second p-well region, the first p-well region and the second p-well region being in an n-doped region over a substrate;
- a first n-type cathode region in the first p-well region;
- a first p-type anode region in the first p-well region, the first n-type cathode region being between the first p-type anode region and the second p-well region, wherein the first p-type anode region has a higher concentration of a p-type dopant than the first p-well region;
- a second n-type cathode region in the second p-well region;
- a second p-type anode region in the second p-well region, the second n-type cathode region being between the second p-type anode region and the first p-well region, wherein the second p-type anode region has a higher concentration of the p-type dopant than the second p-well region;
- a first p-doped tap region in the first p-well region, the first p-doped tap region being between the first n-type cathode region and the second p-well region, the first p-doped tap region having a higher concentration of the p-type dopant than the first p-well region, sidewalls of the first p-doped tap region being covered by the first p-well region, the first p-doped tap region being coupled to the first n-type cathode region via a resistor;
- and
- a second p-doped tap region in the second p-well region, the second p-doped tap region being between the second n-type cathode region and the first p-well region, the second p-doped tap region having a higher concentration of the p-type dopant than the second p-well region.
An ESD protection circuit comprising:
- at least one silicon controlled rectifier (SCR) device comprising:
- a first p-well region disposed in an n-doped region, the first p-well region coupled to a first trigger terminal via a first p-doped tap region, a longitudinal sidewall of the first p-doped tap region being aligned with a longitudinal sidewall of the first p-well region, the first p-doped tap region having a higher concentration of a p-type dopant than the first p-well region, sidewalls of the first p-doped tap region being covered by the first p-well region;
- a second p-well region disposed in the n-doped region, the second p-well region coupled to a second trigger terminal via a second p-doped tap region, a longitudinal sidewall of the second p-doped tap region being aligned with a longitudinal sidewall of the second p-well region, the second p-doped tap region having a higher concentration of the p-type dopant than the second p-well region;
- a first p-type anode region surrounded by the first p-well region and configured to be coupled to a first signal line or supply voltage, the first p-type anode region having a higher concentration of the p-type dopant than the first p-well region;
- a second p-type anode region surrounded by the second p-well region and configured to be coupled to a power supply node, the second p-type anode region having a higher concentration of the p-type dopant than the second p-well region;
- a first n-type cathode region surrounded by the first p-well region and configured to be coupled to the first signal line or supply voltage;
- and
- a second n-type cathode region surrounded by the second p-well region and configured to be coupled to the power supply node, the second n-type cathode region being coupled to the second p-doped tap region via a resistor.
A method of ESD protection using a silicon controlled rectifier (SCR) comprising a first p-well region, a second p-well region, and an n-doped region, the first p-well region coupled to a first trigger terminal via a first p-doped tap region disposed in the first p-well region, the first p-doped tap region having a higher concentration of a p-type dopant than the first p-well region, the first p-doped tap region being coupled via a resistor to an n-type cathode region in the first p-well region, the second p-well region coupled to a second trigger terminal via a second p-doped tap region disposed in the second p-well region, the second p-doped tap region having a higher concentration of the p-type dopant than the second p-well region, the method comprising:
- detecting an ESD pulse using a trigger device;
- activating the SCR via the trigger device upon detection of the ESD pulse, wherein activating the SCR comprises injecting a current through the first p-doped tap region or the second p-doped tap region;
- and
- conducting an ESD current via the SCR.
A silicon controlled rectifier (SCR) device comprising:
- a first well region and a second well region in a substrate, the first well region and the second well region being a first semiconductor type with a first doping concentration, wherein a region of the substrate between the first well region and the second well region is a second semiconductor type, the second semiconductor type being opposite the first semiconductor type;
- a first electrode region in the first well region and a second electrode region in the second well region, the first electrode region and the second electrode region being the second semiconductor type;
- a third electrode region and a first tap region in the first well region, the third electrode region and the first tap region having respective doping concentrations greater than the first doping concentration;
- and
- a fourth electrode region and a second tap region in the second well region, the fourth electrode region and the second tap region having respective doping concentrations greater than the first doping concentration, the second tap region being coupled via a resistor to the second electrode region.
Dependencies are inferred from the claim text.