A reverse conducting power semiconductor device includes a plurality of thyristor cells and a freewheeling diode are integrated in a semiconductor wafer. The freewheeling diode includes a diode anode layer, a diode anode electrode, a diode cathode layer, and a diode cathode electrode. The diode cathode layer includes diode cathode layer segments, each of which is stripe-shaped and arranged within a corresponding stripe-shaped first diode anode layer segment such that a longitudinal main axis of each diode cathode layer segment extends along the longitudinal main axis of the corresponding one of the first diode anode layer segments.

We describe herein a high voltage semiconductor device comprising a power semiconductor device portion (100) and a temperature sensing device portion (185). The temperature sensing device portion comprises: an anode region (140), a cathode region (150), a body region (160) in which the anode region and the cathode region are formed. The temperature sensing device portion also comprises a semiconductor isolation region (165) in which the body region is formed, the semiconductor isolation region having an opposite conductivity type to the body region, the semiconductor isolation region being formed between the power semiconductor device portion and the temperature sensing device portion.

The present disclosure provides a silicon controlled rectifier and a manufacturing method thereof. The silicon controlled rectifier comprises: an N-type well 60, an upper portion of which is provided with a P-type heavily doped region 20 and an N-type heavily doped region 28; an N-type well 62, an upper portion of which is provided with a P-type heavily doped region 22 and an N-type heavily doped region 26; and a P-type well 70 connecting the N-type well 60 and 62, an upper portion of which is provided with a P-type heavily doped region 24; wherein a first electrode structure is in mirror symmetry with a second electrode structure with respect to the P-type heavily doped region 24, and active regions of the N-type well 60 and 62 are respectively provided between the P-type heavily doped region 24 and each of the N-type heavily doped region 28 and 26.

After the various regions of a vertical power device are formed in or on the top surface of an n-type wafer, the wafer is thinned, such as by grinding. A drift layer may be n-type, and various n-type regions and p-type regions in the top surface contact a top metal electrode. A blanket dopant implant through the bottom surface of the thinned wafer is performed to form an n− buffer layer and a bottom p+ emitter layer. Energetic particles are injected through the bottom surface to intentionally damage the crystalline structure. A wet etch is performed, which etches the damaged crystal at a much greater rate, so some areas of the n− buffer layer are exposed. The bottom surface is metallized. The areas where the metal contacts the n− buffer layer form cathodes of an anti-parallel diode for conducting reverse voltages, such as voltage spikes from inductive loads.

A method of forming a semiconductor device includes forming a first vertical protection device comprising a thyristor in a substrate, forming a first lateral trigger element for triggering the first vertical protection device in the substrate, and forming an electrical path in the substrate to electrically couple the first lateral trigger element with the first vertical protection device.

A method of forming a semiconductor device includes forming a first vertical protection device comprising a thyristor in a substrate, forming a first lateral trigger element for triggering the first vertical protection device in the substrate, and forming an electrical path in the substrate to electrically couple the first lateral trigger element with the first vertical protection device.

An insulated gate turn-off (IGTO) device has a PNPN layered structure so that vertical NPN and PNP transistors are formed. Trench gates are formed extending into the intermediate P-layer. The device is formed of an array of cells. A P-channel MOSFET, having a trenched gate, is formed in some of the cells. The control terminal of the IGTO device is connected to the insulated gates of all cells, including to the gate of the P-channel MOSFET, and to the intermediate P-layer. To turn the device on, a positive voltage is applied to the control terminal to turn on the NPN transistor by forward biasing its base-emitter. To turn off the IGTO device, a negative voltage is applied to the control terminal to turn on the P-channel MOSFET to short the NPN base to its emitter.

A semiconductor device of electrostatic discharge (ESD) protection is provided, including a deep N-type region, disposed in a substrate; a deep P-type region, disposed in the substrate; a first P-type well, disposed in the deep N-type region; a first N-type well, abutting to the first P-type well, disposed in the deep N-type region. Further, a second P-type well abutting to the first N-type well is disposed in the deep P-type region. A second N-type well abutting to the second P-type well is disposed in the deep P-type region. A side N-type well is disposed in the deep N-type region at an outer side of the first P-type well. A side P-type well is disposed in the deep P-type region at an outer side of the second N-type well.

A power diode comprises a plurality of diode cells (10). Each diode cell (10) comprises a first conductivity type first anode layer (40), a first conductivity type second anode layer (45) having a lower doping concentration than the first anode layer (40) and being separated from an anode electrode layer (20) by the first anode layer (40), a second conductivity type drift layer (50) forming a pn-junction with the second anode layer (45), a second conductivity type cathode layer (60) being in direct contact with the cathode electrode layer (60), and a cathode-side segmentation layer (67) being in direct contact with the cathode electrode layer (30). A material of the cathode-side segmentation layer (67) is a first conductivity type semiconductor, wherein an integrated doping content of the cathode-side, which is integrated along a direction perpendicular to the second main side (102), is below 2.Math.10.sup.13 cm.sup.−2, or a material of the cathode-side segmentation layer (67) is an insulating material. A horizontal cross-section through each diode cell (10) along a horizontal plane (K1) comprises a first area where the horizontal plane (K1) intersects the second anode layer (45) and a second area where the plane (K1) intersects the drift layer (50).

After the various regions of a vertical power device are formed in or on the top surface of an n-type wafer, the wafer is thinned, such as by grinding. A drift layer may be n-type, and various n-type regions and p-type regions in the top surface contact a top metal electrode. A blanket dopant implant through the bottom surface of the thinned wafer is performed to form an n− buffer layer and a bottom p+ emitter layer. Energetic particles are injected through the bottom surface to intentionally damage the crystalline structure. A wet etch is performed, which etches the damaged crystal at a much greater rate, so some areas of the n− buffer layer are exposed. The bottom surface is metallized. The areas where the metal contacts the n− buffer layer form cathodes of an anti-parallel diode for conducting reverse voltages, such as voltage spikes from inductive loads.