Abstract: A junction field effect transistor includes a substrate and a gate region having a first conductive type in the substrate. Source/drain regions of a second conductive type opposite to the first conductive type are disposed in the substrate on opposite sides of the gate region. A pair of high-voltage well regions of the second conductive type are disposed beneath the source/drain regions. A channel region is provided beneath the gate region and between the pair of high-voltage well regions. The channel region is of the second conductive type and has a dopant concentration lower than that of the pair of high-voltage well regions.

Abstract: An ultra-high voltage device is provided. The ultra-high voltage device includes a substrate, a first well zone formed in the substrate, a second well zone having a surface formed in the substrate adjacent to the first well zone, a gate oxide formed on the first well zone and the second well zone of the substrate, a gate formed on the gate oxide, a channel formed in the first well zone underneath the gate oxide, an accumulation region formed in the second well zone underneath the gate oxide adjacent to the channel, wherein only a part of the accumulation region is implanted with a dopant to form an implant region therein, and an insulation region formed on the surface of the second well zone of the substrate adjacent to the accumulation region, wherein a boundary is formed between the insulation region and the accumulation region.

Abstract: A semiconductor device includes a semiconductor substrate, a first well region, and a second well region. The semiconductor substrate has a first conductivity type. The first and second well regions are disposed in the semiconductor substrate. The first and second well regions have a second conductivity type that is opposite to the first conductivity type. The semiconductor device also includes a first top layer and a second top layer. The first top layer is disposed in the semiconductor substrate. The first top layer extends from the first well region to the second well region. The first top layer has the first conductivity type. The second top layer is disposed in the semiconductor substrate and on the first top layer. The second top layer extends from the first well region to the second well region. The second top layer has the second conductivity type.

Abstract: A high-voltage semiconductor device includes a MOS device and a resistor device. The MOS device has a source, a drain, a drain insulation region adjacent to the drain, and a gate adjacent to the source. The resistor device is formed on the drain insulation region and is electrically connected to the drain. The resistor device has a plurality of resistor sections connected in series, and each of the plurality of resistor sections has a curved shape.

Abstract: An ultra-high voltage device is provided. The ultra-high voltage device includes a substrate, a first well zone formed in the substrate, a second well zone formed in the substrate adjacent to the first well zone, a gate oxide layer formed on the first well zone and the second well zone, a gate formed on the gate oxide layer, an insulation region formed on the surface of the second well zone, a first implant region formed in the second well zone underneath the insulation region, a second implant region formed below the first implant region, and a junction formed between the first implant region and the second implant region. At least one of the first implant region and the second implant region includes at least two sub-implant regions having different implant concentrations. The sub-implant region having the higher implant concentration is adjacent to the junction.

Abstract: A high-voltage semiconductor device is provided. The device includes a semiconductor substrate having a first conductivity type, and a first doping region having a second conductivity type therein. An epitaxial layer is on the semiconductor substrate. A body region having the first conductivity type is in the epitaxial layer on the first doping region. A second doping region and a third doping region that have the second conductivity type are respectively in the epitaxial layer on both opposite sides of the body region, so as to adjoin the body region. Source and drain regions are respectively in the body region and the second doping region. A field insulating layer is in the second doping region between the source and drain regions. A gate structure is on the epitaxial layer to cover a portion of the field insulating layer.

Abstract: A semiconductor substrate structure includes a seed layer on a substrate, a first gallium nitride layer on the seed layer, and a patterned first hard mask layer on the first gallium nitride layer, wherein the patterned first hard mask layer includes a first opening. The semiconductor substrate structure also includes a second gallium nitride layer in the first opening and on the patterned first hard mask layer, a patterned second hard mask layer on the second gallium nitride layer, wherein the patterned second hard mask layer includes a second opening, and at least a portion of a projection on the substrate of the first opening and a projection on the substrate of the second opening are non-overlapped. The semiconductor substrate structure further includes a third gallium nitride layer in the second opening and on the patterned second hard mask layer.

Abstract: A high-voltage semiconductor structure including a substrate, a first doped region, a well, a second doped region, a third doped region, a fourth doped region, and a gate structure is provided. The substrate has a first conductive type. The first doped region has the first conductive type and is formed in the substrate. The well has a second conductive type and is formed in the substrate. The second doped region has the second conductive type and is formed in the first doped region. The third doped region has the first conductive type and is formed in the well. The fourth doped region has the second conductive type and is formed in the well. The gate structure is disposed over the substrate and partially covers the first doped region and the well.

Abstract: A high-voltage semiconductor structure including a substrate, a first doped region, a well, a second doped region, a third doped region, a fourth doped region, and a gate structure is provided. The substrate has a first conductive type. The first doped region has the first conductive type and is formed in the substrate. The well has a second conductive type and is formed in the substrate. The second doped region has the second conductive type and is formed in the first doped region. The third doped region has the first conductive type and is formed in the well. The fourth doped region has the second conductive type and is formed in the well. The gate structure is disposed over the substrate and partially covers the first doped region and the well.

Abstract: A semiconductor device is provided. The device may include a semiconductor layer; and a doped well disposed in the semiconductor layer and having a first conductivity type. The device may also include a drain region, a source region, and a body region, where the source and body regions may operate in different voltages. Further, the device may include a first doped region having a second conductivity type, the first doped region disposed between the source region and the doped well; and a second doped region having the first conductivity type and disposed under the source region. The device may include a third doped region having the second conductivity type and disposed in the doped well; and a fourth doped region disposed above the third doped region, the fourth doped region having the first conductivity type. Additionally, the device may include a gate and a field plate.

Abstract: A semiconductor device is provided. The semiconductor device includes a first conductive type substrate; a second conductive type body region disposed in the first conductive type substrate, wherein the first conductive type is different from the second conductive type; a first conductive type first well region disposed in the second conductive type body region; a gate structure disposed over the top surface of the first conductive type substrate; a source region, wherein the source region includes a heavily-doped first conductive type source region and is disposed in the second conductive type body region; and a drain region, wherein the drain region is heavily doped first conductive type and is disposed in the first conductive type first well region.

Abstract: A semiconductor device is provided. The device includes a substrate having a first conductivity type. The device further includes a drain region, a source region, and a well region disposed in the substrate. The well region is disposed between the drain region and the source region and having a second conductivity type opposite to the first conductivity type. The device further includes a plurality of doped regions disposed within the well region. The doped regions are vertically and horizontally offset from each other. Each of the doped regions includes a lower portion having the first conductivity type, and an upper portion stacked on the lower region and having the second conductivity type.

Abstract: A semiconductor device is provided. The device may include a semiconductor layer; and a doped well disposed in the semiconductor layer and having a first conductivity type. The device may also include a drain region, a source region, and a body region, where the source and body regions may operate in different voltages. Further, the device may include a first doped region having a second conductivity type, the first doped region disposed between the source region and the doped well; and a second doped region having the first conductivity type and disposed under the source region. The device may include a third doped region having the second conductivity type and disposed in the doped well; and a fourth doped region disposed above the third doped region, the fourth doped region having the first conductivity type. Additionally, the device may include a gate and a field plate.

Abstract: A switch-mode converter includes a high-side driver, a high-side transistor, a low-side driver, a low-side transistor, a capacitor, and an active diode. The high-side driver is supplied by the bootstrap voltage of the bootstrap node and a floating reference voltage of a floating reference node, and generates the high-side output signal. The high-side transistor provides an input voltage to the floating reference node according to the high-side output signal. The low-side driver generates the low-side output signal. The low-side transistor couples the floating reference node to a ground according to the low-side output signal. The capacitor is coupled between the bootstrap node and the floating reference node. The active diode provides the supply voltage to the bootstrap node. When the bootstrap voltage exceeds the supply voltage, the active diode isolates the supply voltage from the bootstrap node.

Abstract: A high-side circuit, adapted for a switched-mode converter, includes a level shifter, a high-side driver, a high-side transistor, a capacitor, and an active diode. The level shifter receives a first signal to generate a set signal. The high-side driver is supplied by a bootstrap voltage of a bootstrap node and a floating reference voltage of a floating reference node, which controls the high-side transistor to provide an input voltage to the floating reference node according to the set signal. The capacitor is coupled between the bootstrap node and the floating reference node. The active diode provides a supply voltage to the bootstrap node. When the bootstrap voltage exceeds the supply voltage, the active diode isolates the supply voltage from the bootstrap node according to a control voltage. The active diode includes a first-type well coupled to the bootstrap node, where the high-side driver is disposed.

Abstract: A high-side circuit, adapted for a switched-mode converter, includes a level shifter, a high-side driver, a high-side transistor, a capacitor, and an active diode. The level shifter receives a first signal to generate a set signal. The high-side driver is supplied by a bootstrap voltage of a bootstrap node and a floating reference voltage of a floating reference node, which controls the high-side transistor to provide an input voltage to the floating reference node according to the set signal. The capacitor is coupled between the bootstrap node and the floating reference node. The active diode provides a supply voltage to the bootstrap node. When the bootstrap voltage exceeds the supply voltage, the active diode isolates the supply voltage from the bootstrap node according to a control voltage. The active diode includes a first-type well coupled to the bootstrap node, where the high-side driver is disposed.

Abstract: A semiconductor device is provided. The device includes a substrate having a first conductivity type. The device further includes a drain region, a source region, and a well region disposed in the substrate. The well region is disposed between the drain region and the source region and having a second conductivity type opposite to the first conductivity type. The device further includes a plurality of doped regions disposed within the well region. The doped regions are vertically and horizontally offset from each other. Each of the doped regions includes a lower portion having the first conductivity type, and an upper portion stacked on the lower region and having the second conductivity type.

Abstract: A semiconductor device includes: a semiconductor substrate; a semiconductor layer disposed over the semiconductor layer; a first well region disposed in the semiconductor layer and the semiconductor substrate; a second well region disposed in the semiconductor layer; a first isolation element disposed in the first well region; a second isolation element disposed in the second well region; a gate structure disposed in the semiconductor layer between the first isolation element and the second isolation element; a first doped region disposed in the first well region; and a second doped region disposed in the second well region. The bottom surface of the gate structure is above, below or substantially level with a bottom surface of the first isolation structure.

Abstract: A semiconductor device is provided. The semiconductor device includes a substrate of a first conductivity type and an epitaxial structure of the first conductivity type disposed on the substrate. The semiconductor device further includes a well region having a first doping concentration of a second conductivity type disposed in the epitaxial structure and the substrate. The semiconductor device further includes a drain region and a source region respectively formed in the epitaxial structure inside and outside of the well region. The semiconductor device further includes a body region of the first conductivity type disposed under the source region, and a pair of first and second doped regions disposed in the well region between the drain region and the source region. The first and second doped regions extend outside of the well region and toward the body region.

Abstract: A semiconductor device includes: a semiconductor substrate; a semiconductor layer disposed over the semiconductor layer; a first well region disposed in the semiconductor layer and the semiconductor substrate; a second well region disposed in the semiconductor layer; a first isolation element disposed in the first well region; a second isolation element disposed in the second well region; a gate structure disposed in the semiconductor layer between the first isolation element and the second isolation element; a first doped region disposed in the first well region; and a second doped region disposed in the second well region. The bottom surface of the gate structure is above, below or substantially level with a bottom surface of the first isolation structure.