Abstract: High-voltage transistor devices with two-step field plate structures and methods of fabricating the transistor devices are provided. An example high voltage transistor device includes: a gate electrode disposed over a substrate between a source region and a drain region, a first film laterally extending from over the gate electrode to over a drift region laterally arranged between the gate electrode and the drain region, a second film laterally extending over a portion of the drift region adjacent to the drain region and away from the gate electrode, and a field plate laterally extending from over the first film to over the second film. A first thickness vertically from a top surface of the gate electrode to a bottom surface of the field plate is smaller than a second thickness vertically from a top surface of the portion of the drift region to the bottom surface of the field plate.

Abstract: High-voltage transistor devices with two-step field plate structures and methods of fabricating the transistor devices are provided. An example high voltage transistor device includes: a gate electrode disposed over a substrate between a source region and a drain region, a first film laterally extending from over the gate electrode to over a drift region laterally arranged between the gate electrode and the drain region, a second film laterally extending over a portion of the drift region adjacent to the drain region and away from the gate electrode, and a field plate laterally extending from over the first film to over the second film. A first thickness vertically from a top surface of the gate electrode to a bottom surface of the field plate is smaller than a second thickness vertically from a top surface of the portion of the drift region to the bottom surface of the field plate.

Abstract: A LDMOS transistor device includes a substrate including a first insulating structure formed therein, a gate formed on the substrate and covering a portion of the first insulating structure, a drain region and a source region formed in the substrate at two respective sides of the gate, a base region encompassing the source region, and a doped layer formed under the base region. The drain region and the source region include a first conductivity type, the base region and the doped layer include a second conductivity type, and the second conductivity type is complementary to the first conductivity type. A top of the doped layer contacts a bottom of the base region. A width of the doped layer is larger than a width of the base region.

Abstract: A LDMOS transistor device includes a substrate including a first insulating structure formed therein, a gate formed on the substrate and covering a portion of the first insulating structure, a drain region and a source region formed in the substrate at two respective sides of the gate, a base region encompassing the source region, and a doped layer formed under the base region. The drain region and the source region include a first conductivity type, the base region and the doped layer include a second conductivity type, and the second conductivity type is complementary to the first conductivity type. A top of the doped layer contacts a bottom of the base region. A width of the doped layer is larger than a width of the base region.

Abstract: A lateral-diffused metal oxide semiconductor device (LDMOS) includes a substrate, a first deep well, at least a field oxide layer, a gate, a second deep well, a first dopant region, a drain and a common source. The substrate has the first deep well which is of a first conductive type. The gate is disposed on the substrate and covers a portion of the field oxide layer. The second deep well having a second conductive type is disposed in the substrate and next to the first deep well. The first dopant region having a second conductive type is disposed in the second deep well. The doping concentration of the first dopant region is higher than the doping concentration of the second deep well.

Abstract: A Schottky diode having a current leakage protection structure includes a Schottky diode unit, a first isolation portion and a second isolation portion. The Schottky diode unit is defined in a substrate and includes a metalized anode, an active region having dopants of first conductive type, a cathode and at least one isolation structure. The first isolation portion having dopants of second conductive type is formed between substrate and active region, and the first isolation portion includes a first well disposed beneath active region, and a first guard ring surrounding active region and connecting to the first well. The second isolation portion having dopants of first conductive type is formed between substrate and the first isolation portion, and the second isolation portion includes a second well disposed beneath the first well, and a second guard ring surrounding the first guard ring and connecting to the second well.

Abstract: A lateral diffusion metal-oxide-semiconductor (LDMOS) transistor structure comprises a barrier layer, a semiconductor layer, a source, a first drain and a guard ring. The barrier layer with a first polarity is disposed in a substrate. The semiconductor layer with a second polarity is disposed on the barrier layer. The source has a first polarity region and a second polarity region both formed in the semiconductor layer. The first drain is disposed in the semiconductor layer and has a drift region with the second polarity. The guard ring with the first polarity extends downward from a surface of the semiconductor layer in a manner of getting in touch with the barrier layer and to surround the source and the drain, and is electrically connected to the source.

Abstract: A lateral-diffused metal oxide semiconductor device (LDMOS) includes a substrate, a first deep well, at least a field oxide layer, a gate, a second deep well, a first dopant region, a drain and a common source. The substrate has the first deep well which is of a first conductive type. The gate is disposed on the substrate and covers a portion of the field oxide layer. The second deep well having a second conductive type is disposed in the substrate and next to the first deep well. The first dopant region having a second conductive type is disposed in the second deep well. The doping concentration of the first dopant region is higher than the doping concentration of the second deep well.

Abstract: A lateral diffusion metal-oxide-semiconductor (LDMOS) transistor structure comprises a barrier layer, a semiconductor layer, a source, a first drain and a guard ring. The barrier layer with a first polarity is disposed in a substrate. The semiconductor layer with a second polarity is disposed on the barrier layer. The source has a first polarity region and a second polarity region both formed in the semiconductor layer. The first drain is disposed in the semiconductor layer and has a drift region with the second polarity. The guard ring with the first polarity extends downward from a surface of the semiconductor layer in a manner of getting in touch with the barrier layer and to surround the source and the drain, and is electrically connected to the source.

Abstract: The present invention provides a lateral diffused metal-oxide-semiconductor device including a first doped region, a second doped region, a third doped region, a gate structure, and a contact metal. The first doped region and the third doped region have a first conductive type, and the second doped region has a second conductive type. The second doped region, which has a racetrack-shaped layout, is disposed in the first doped region, and has a long axis. The third doped region is disposed in the second doped region. The gate structure is disposed on the first doped region and the second doped region at a side of the third doped region. The contact metal is disposed on the first doped region at a side of the second doped region extending out along the long axis, and is in contact with the first doped region.

Abstract: A lateral-diffused metal oxide semiconductor device (LDMOS) includes a substrate, a first deep well, at least a field oxide layer, a gate, a second deep well, a first dopant region, a drain and a common source. The substrate has the first deep well which is of a first conductive type. The gate is disposed on the substrate and covers a portion of the field oxide layer. The second deep well having a second conductive type is disposed in the substrate and next to the first deep well. The first dopant region having a second conductive type is disposed in the second deep well. The doping concentration of the first dopant region is higher than the doping concentration of the second deep well.

Abstract: A high voltage semiconductor device is provided. A first-polarity buried layer is formed in the substrate. A first high voltage second-polarity well region is located over the first-polarity buried layer. A second-polarity base region is disposed within the first high voltage second-polarity well region. A source region is disposed within the second-polarity base region. A high voltage deep first-polarity well region is located over the first-polarity buried layer and closely around the first high voltage second-polarity well region. A first-polarity drift region is disposed within the high voltage deep first-polarity well region. A gate structure is disposed over the substrate. A second high voltage second-polarity well region is located over the first-polarity buried layer and closely around the high voltage deep first-polarity well region. A deep first-polarity well region is located over the first-polarity buried layer and closely around the second high voltage second-polarity well region.

Abstract: The present invention provides a lateral diffused metal-oxide-semiconductor device including a first doped region, a second doped region, a third doped region, a gate structure, and a contact metal. The first doped region and the third doped region have a first conductive type, and the second doped region has a second conductive type. The second doped region, which has a racetrack-shaped layout, is disposed in the first doped region, and has a long axis. The third doped region is disposed in the second doped region. The gate structure is disposed on the first doped region and the second doped region at a side of the third doped region. The contact metal is disposed on the first doped region at a side of the second doped region extending out along the long axis, and is in contact with the first doped region.

Abstract: A lateral-diffusion metal-oxide-semiconductor device includes a semiconductor substrate having at least a field oxide layer, a gate having a layout pattern of a racetrack shape formed on the substrate, a common source formed in the semiconductor substrate and enclosed by the gate, and a drain surrounding the gate and formed in the semiconductor substrate. The gate covers a portion of the field oxide layer. The common source includes a first doped region having a first conductive type and a plurality of islanding second doped regions having a second conductive type. The drain includes a third doped region having the first conductive type. The third doped region overlaps a portion of the field oxide layer and having an overlapping area between the third doped region and the field oxide layer.

Abstract: A high voltage semiconductor device is provided. A first-polarity buried layer is formed in the substrate. A first high voltage second-polarity well region is located over the first-polarity buried layer. A second-polarity base region is disposed within the first high voltage second-polarity well region. A source region is disposed within the second-polarity base region. A high voltage deep first-polarity well region is located over the first-polarity buried layer and closely around the first high voltage second-polarity well region. A first-polarity drift region is disposed within the high voltage deep first-polarity well region. A gate structure is disposed over the substrate. A second high voltage second-polarity well region is located over the first-polarity buried layer and closely around the high voltage deep first-polarity well region. A deep first-polarity well region is located over the first-polarity buried layer and closely around the second high voltage second-polarity well region.

Abstract: A lateral-diffused metal oxide semiconductor device (LDMOS) includes a substrate, a first deep well, at least a field oxide layer, a gate, a second deep well, a first dopant region, a drain and a common source. The substrate has the first deep well which is of a first conductive type. The gate is disposed on the substrate and covers a portion of the field oxide layer. The second deep well having a second conductive type is disposed in the substrate and next to the first deep well. The first dopant region having a second conductive type is disposed in the second deep well. The doping concentration of the first dopant region is higher than the doping concentration of the second deep well.

Abstract: A lateral-diffusion metal-oxide-semiconductor device includes a semiconductor substrate having at least a field oxide layer, a gate having a layout pattern of a racetrack shape formed on the substrate, a common source formed in the semiconductor substrate and enclosed by the gate, and a drain surrounding the gate and formed in the semiconductor substrate. The gate covers a portion of the field oxide layer. The common source includes a first doped region having a first conductive type and a plurality of islanding second doped regions having a second conductive type. The drain includes a third doped region having the first conductive type. The third doped region overlaps a portion of the field oxide layer and having an overlapping area between the third doped region and the field oxide layer.

Abstract: A lateral-diffusion metal-oxide-semiconductor device includes a source in a racetrack shaped active area, a first field oxide region isolating and surrounding the racetrack shaped active area, a racetrack shaped gate surrounding the source, and a drain disposed at one side of the gate opposite to the source. The source includes a P+ doping region in a P well and an N+ doping region butting on the P+ doping region.

Abstract: A method of manufacturing a lateral diffusion metal oxide semiconductor device includes following steps. First, a substrate having a first conductive type is provided. The substrate has a well, and the well has a second conductive type. Then, a body region is formed in the well, and a channel defining region is formed in the body region. The body region has the second conductive type, and the channel defining region has the first conductive type, so that the body region disposed between the channel defining region and the well and uncovered with the channel defining region forms a channel of the lateral diffusion metal oxide semiconductor device. Then, a gate structure is formed on the channel.