A semiconductor device includes a semiconductor layer of a first conductivity type that has a main surface and that includes a device region, a base region of a second conductivity type that is formed in a surface layer portion of the main surface at the device region, a source region of the first conductivity type that is formed in a surface layer portion of the base region at an interval inward from a peripheral portion of the base region and that defines a channel region with the semiconductor layer, a base contact region of the second conductivity type that is formed in a region different from the source region at the surface layer portion of the base region and that has an impurity concentration exceeding an impurity concentration of the base region, a well region of the first conductivity type that is formed in the surface layer portion of the main surface at an interval from the base region at the device region and that defines a drift region with the base region, a drain region of the first conductivity type that is formed in a surface layer portion of the well region, an impurity region of the second conductivity type that is formed in the surface layer portion of the well region and that is electrically connected to the drain region, and a gate structure that has a gate insulating film covering the channel region on the main surface and a gate electrode facing the channel region on the gate insulating film and electrically connected to the source region and the base contact region.

A system having a device for conducting an electrostatic discharge (ESD) current from a designated pin node. The system includes first and second pin nodes, and a switching device having a first switching threshold. The switching device includes a first, terminal coupled to a reference node, and a second terminal, coupled to the first pin node to actuate the switching device to conduct ESD current from the first pin node responsive to a voltage between the first pin node and the reference node exceeding the first switching threshold. The switching device further includes a third terminal, coupled to the second pin node, to actuate the switching device to conduct ESD current from the first pin node responsive to a voltage between the first pin node and the second pin node exceeding a second switching threshold.

A high voltage device is used as a lower switch in a power stage of a switching regulator. The high voltage device includes at least one lateral diffused metal oxide semiconductor (LDMOS) device, a first isolation region, a second isolation region, a third isolation region, and a current limiting device. The first isolation region is located in a semiconductor layer, and encloses the LDMOS device. The second isolation region has a first conductivity type, and encloses the first isolation region in the semiconductor layer. The third isolation region has a second conductivity type, and encloses the second isolation region in the semiconductor layer. The current limiting device is electrically connected to the second isolation region, and is configured to operably suppress a parasitic silicon controlled rectifier (SCR) from being turned on.

An ESD protection device may include a substrate having first and second substrate layers, and first and second bridged regions. Each substrate layer may include first and second border regions and a middle region laterally therebetween. Each bridged region may be arranged within the middle region and a respective border region of the second substrate layer. The middle region of the second substrate layer may be laterally narrower than the middle region of the first substrate layer. Each border region of the second substrate layer may be partially arranged over the middle region of the first substrate layer and partially arranged over a respective border region of the first substrate layer. The border regions of the substrate layers, and the bridged regions may have a first conductivity type, and the middle regions of the substrate layers may have a second conductivity type different from the first conductivity type.

A protection device may include a semiconductor substrate and a thyristor-type device, formed within the semiconductor substrate, where the thyristor device extends from a first main surface of the semiconductor substrate to a second main surface of the semiconductor substrate. The protection device may include a first PN diode, formed within the semiconductor substrate; and a second PN diode, formed within the semiconductor substrate, wherein the thyristor-type device is arranged in electrical series between the first PN diode and the second PN diode.

In embodiments, an integrated circuit is provided that includes an input/output cell having a first signal terminal and a second signal terminal connected to a domain and capable of withstanding a maximum voltage greater than the power supply voltage. The input/output cell further includes an array of N diodes coupled in series between the second signal terminal and a cold power supply point. The array has an overall threshold voltage greater than the maximum voltage. The integrated circuit further includes a control circuit connected between the first signal terminal and the array of diodes. The control circuit is configured, in the presence of a second voltage on the first signal terminal greater than the maximum voltage, to automatically and autonomously short-circuit at least one of the diodes in the array to limit the voltage on the second signal terminal to a third voltage less than the maximum voltage.

Disclosed is a semiconductor structure including a semiconductor substrate (e.g., a P-substrate) and a symmetric BDSCR. The BDSCR includes, within the substrate, a first well (e.g., a low-doped deep Nwell) and, within the first well, symmetric side sections and a middle section positioned laterally between the side sections. Each side section includes: second and third wells (e.g., Pwells), where the third well is shallower than and has a higher conductivity level than the second well. Each middle section includes multiple floating wells including: two fourth wells (e.g., Nwells), which have a higher conductivity level than the first well, and a fifth well (e.g., another Pwell), which is positioned laterally between and shallower than the fourth wells. By incorporating the floating wells into the middle section, high current tolerance is improved.

A transient voltage suppression device includes a P-type semiconductor layer, a first N-type well, a first N-type heavily-doped area, a first P-type heavily-doped area, a second P-type heavily-doped area, and a second N-type heavily-doped area. The first N-type well and the second N-type heavily-doped area are formed in the layer. The first P-type heavily-doped area is formed in the first N-type well. The first P-type heavily-doped area is spaced from the bottom of the first N-type well. The second P-type heavily-doped area is formed within the first N-type well and spaced from the sidewall of the first N-type well. The second P-type heavily-doped area is formed between the first P-type heavily-doped area and the second N-type heavily-doped area.

Disclosed are a transistor structure for electrostatic protection and a method for manufacturing the same. The transistor structure comprises: a doped region in a substrate; field oxide layers; a first N-type well region, a P-type well region and a second N-type well region in the doped region and spaced in sequence; a first polycrystalline silicon layer and a second polycrystalline silicon layer covering part of the P-type well region; a first N+ region and a first P+ region respectively formed in the first N-type well region and the second N-type well region second P+ region and the second N+ region are close to the first N+ region and the first P+ region, respectively. The structure may change a current path under forward/reverse operation; thus, a device keeps a good electrostatic protection capability and high robustness.

The electrostatic discharge protection apparatus includes a substrate, a first well having a first conductivity type and disposed in the substrate, a second well having a second conductivity type and disposed in the first well, a first doping region having the first conductivity type and disposed in the second well, a second doping region having the first conductivity type and disposed in the second well, a third doping region having the second conductivity type and disposed in the second well, and a fourth doping region having the first conductivity type and disposed in the substrate. The first conductivity type is different from the second conductivity type. The second well, the first well, the substrate and the fourth doping region form a silicon controlled rectifier. Electrostatic discharge current flowing into the first doping region flows to the fourth doping region through the silicon controlled rectifier.