Abstract: A method of fabricating a semiconductor integrated circuit including a power diode includes providing a semiconductor substrate of first conductivity type, fabricating a integrated circuit such as a CMOS transistor circuit in a first region of the substrate, and fabricating a power diode in a second region in the semiconductor substrate. Dielectric material is formed between the first region and the second regions thereby providing electrical isolation between the integrated circuit in the first region and the power diode in the second region. The power diode can comprise a plurality of MOS source/drain elements and associated gate elements all connected together by one electrode of the diode, and a semiconductor layer in the second region can function as another source/drain of the power diode.

Abstract: A power device having vertical current flow through a semiconductor body of one conductivity type from a top electrode to a bottom electrode includes at least one gate electrode overlying a gate insulator on a first surface of the body, a channel region of second conductivity type in the surface of the body underlying all of the gate electrode, a first doped region of the second conductivity type contiguous with the channel region and positioned deeper in the body than the channel region and under a peripheral region of the gate electrode, and a second doped source/drain region in the surface of the body abutting the channel region and adjacent to the gate electrode. When the gate is forward biased, an inversion region extends through the channel region and electrically connects the first electrode and the second electrode with a small Vf near to the area between adjacent P bodies being flooded with electrons and denuded of holes. Therefore, at any forward bias this area conducts as an N-type region.

Abstract: A two-terminal power diode has improved reverse bias breakdown voltage and on resistance includes a semiconductor body having two opposing surfaces and a superjunction structure therebetween, the superjunction structure including a plurality of alternating P and N doped regions aligned generally perpendicular to the two surfaces. The P and N doped regions can be parallel stripes or a mesh with each region being surrounded by doped material of opposite conductivity type. A diode junction associated with one surface can be an anode region with a gate controlled channel region connecting the anode region to the superjunction structure. Alternatively, the diode junction can comprise a metal forming a Schottky junction with the one surface. The superjunction structure is within the cathode and spaced from the anode. The spacing can be varied during device fabrication.

Abstract: A power device having vertical current flow through a semiconductor body of one conductivity type from a top electrode to a bottom electrode includes at least one gate electrode overlying a gate insulator on a first surface of the body, a channel region of second conductivity type in the surface of the body underlying all of the gate electrode, a first doped region of the second conductivity type contiguous with the channel region and positioned deeper in the body than the channel region and under a peripheral region of the gate electrode, and a second doped source/drain region in the surface of the body abutting the channel region and adjacent to the gate electrode. When the gate is forward biased, an inversion region extends through the channel region and electrically connects the first electrode and the second electrode with a small Vf near to the area between adjacent P bodies being flooded with electrons and denuded of holes. Therefore, at any forward bias this area conducts as an N-type region.

Abstract: A method for manufacturing a discrete power rectifier device having a VLSI multi-cell design employs a two spacer approach to defining a P/N junction profile having good breakdown voltage characteristics. The method provides highly repeatable device characteristics at reduced cost. The active channel regions of the device are also defined using the same two spacers. The method is a self-aligned process and channel dimensions and doping characteristics may be precisely controlled despite inevitable process variations in spacer formation. Only two masking steps are required, and additional spacers for defining the body region profile can be avoided, reducing processing costs.

Abstract: A semiconductor current limiting device is provided by a two-terminal vertical N(P)-channel MOSFET device having the gate, body, and source terminals tied together as the anode and the drain terminal as the cathode. The doping profile of the body is so tailored with ion implantation that a depletion region pinches off to limit current. The body comprises a shallow implant to form a MOS channel and an additional deep implant through a spacer shielding the channel area. Implanted a higher energies and at an acute angle, the deep implant protrudes into the regular current path of the vertical MOSFET.

Abstract: A two-terminal power diode has improved reverse bias breakdown voltage and on resistance includes a semiconductor body having two opposing surfaces and a superjunction structure therebetween, the superjunction structure including a plurality of alternating P and N doped regions aligned generally perpendicular to the two surfaces. The P and N doped regions can be parallel stripes or a mesh with each region being surrounded by doped material of opposite conductivity type. A diode junction associated with one surface can be an anode region with a gate controlled channel region connecting the anode region to the superjunction structure. Alternatively, the diode junction can comprise a metal forming a Schottky junction with the one surface. The superjunction structure is within the cathode and spaced from the anode. The spacing can be varied during device fabrication.

Abstract: A power rectifier having low on resistance, fast recovery time and low forward voltage drop. In a preferred embodiment, the present invention provides a power rectifier device employing a vertical device structure, i.e., with current flow between the major surfaces of the discrete device. The device employs a large number of parallel connected cells, each comprising a MOSFET structure with a gate to drain short via a common conductive layer. This provides a low Vf path through the channel regions of the MOSFET cells to the contact metallization on the other side of the integrated circuit. A thin gate structure is formed annularly around pedestal regions on the upper surface of the device and a precisely controlled body implant defines the channel region and allows controllable device characteristics, including gate threshold voltage and Vf.

Abstract: A semiconductor rectifying device which emulates the characteristics of a low forward voltage drop Schottky diode and which is capable of a variety of electrical characteristics from less than 1 A to greater than 1000 A current with adjustable breakdown voltage. The manufacturing process provides for uniformity and controllability of operating parameters, high yield, and readily variable device sizes. The device includes a semiconductor body with a guard ring on one surface to define a device region in which are optionally formed a plurality of conductive plugs. Between the guard ring and the conductive plugs are a plurality of source/drain, gate and channel elements which function with the underlying substrate in forming a MOS transistor.

Abstract: A Schottky diode comprises a semiconductor body of one conductivity type, the semiconductor body having a grooved surface, a metal layer on the grooved surface and forming a Schottky junction with sidewalls of the grooved surface and ohmic contacts with top portions of the grooved surface. The semiconductor body preferably includes a silicon substrate with the grooved surface being on a device region defined by a guard ring of a conductivity type opposite to the conductivity type of the semiconductor body, and a plurality of doped regions at the bottom of grooves and forming P-N junctions with the semiconductor body. The P-N junctions of the doped regions form carrier depletion regions across and spaced from the grooves to increase the reverse bias breakdown voltage and reduce the reverse bias leakage current. The ohmic contacts of the metal layer increase forward current and reduce forward voltage of the Schottky diode.

Abstract: A vertical semiconductor rectifier device includes a semiconductor substrate of first conductivity type and having a plurality of gates insulatively formed on a first major surface and a plurality of source/drain regions of the first conductivity type formed in surface regions of second conductivity type in the first major surface adjacent to the gates. A plurality of channels of the second conductivity type each abuts a source/drain region and extends under a gate.

Abstract: A Schottky diode comprises a semiconductor body of one conductivity type, the semiconductor body having a grooved surface, a metal layer on the grooved surface and forming a Schottky junction with the semiconductor body. The semiconductor body preferably includes a silicon substrate with the grooved surface being on a device region defined by a guard ring of a conductivity type opposite to the conductivity type of the semiconductor body, and a plurality of doped regions at the bottom of grooves and forming P-N junctions with the semiconductor body. The P-N junctions of the doped regions form carrier depletion regions across and spaced from the grooves to increase the reverse bias breakdown voltage and reduce the reverse bias leakage current.

Abstract: A Schottky diode comprises a semiconductor body of one conductivity type, the semiconductor body having a grooved surface, and a metal layer on the grooved surface and forming a Schottky junction with the semiconductor body. The semiconductor body preferably includes a silicon substrate with the grooved surface being on a device region defined by a guard ring of a conductivity type opposite to the conductivity type of the semiconductor body.