Alpha & Omega Semiconductor Patent Grants

Trench junction barrier controlled Schottky

Granted: August 22, 2017
Patent Number: 9741851
A method for manufacturing a Schottky diode comprising steps of 1) providing a region with a dopant of a second conductivity type opposite to a first conductivity type to form a top doped region in a semiconductor substrate of said first conductivity type; 2) providing a trench through the top doped region to a predetermined depth and providing a dopant of the second conductivity type to form a bottom dopant region of the second conductivity type; and 3) lining a Schottky barrier metal…

Alternating current injection for constant-on time buck converter—a regulator control method

Granted: August 22, 2017
Patent Number: 9742276
The present invention discloses a voltage control method. At first, the load voltage of the load is divided to generate a feedback voltage. The feedback voltage and a triangular wave of a triangular wave periodic signal, including the positive voltage and negative voltage, are combined to generate a sum signal. The sum signal is compared with a target voltage, and when the sum signal is less than the target voltage signal, a control signal is generated to control the switches to turn on…

Combined packaged power semiconductor device

Granted: August 15, 2017
Patent Number: 9735094
A combined packaged power semiconductor device includes flipped top source low-side MOSFET electrically connected to top surface of a die paddle, first metal interconnection plate connecting between bottom drain of a high-side MOSFET or top source of a flipped high-side MOSFET to bottom drain of the low-side MOSFET, and second metal interconnection plate stacked on top of the high-side MOSFET chip. The high-side, low-side MOSFET and the IC controller can be packaged three-dimensionally…

Termination structure for gallium nitride schottky diode

Granted: August 8, 2017
Patent Number: 9728655
A termination structure for a nitride-based Schottky diode includes a guard ring formed by an epitaxially grown P-type nitride-based compound semiconductor layer and dielectric field plates formed on the guard ring. The termination structure is formed at the edge of the anode electrode of the Schottky diode and has the effect of reducing electric field crowding at the anode electrode edge, especially when the Schottky diode is reverse biased. In one embodiment, the P-type epitaxial layer…

Vertical DMOS transistor

Granted: August 1, 2017
Patent Number: 9722069
A transistor includes a semiconductor body; a body region of a first conductivity type formed in the semiconductor body; a gate electrode formed partially overlapping the body region and insulated from the semiconductor body by a gate dielectric layer; a source diffusion region of a second conductivity type formed in the body region on a first side of the gate electrode; a trench formed in the semiconductor body on a second side, opposite the first side, of the gate electrode, the trench…

Lateral super-junction MOSFET device and termination structure

Granted: August 1, 2017
Patent Number: 9722073
A lateral superjunction MOSFET device includes a gate structure and a first column connected to the lateral superjunction structure. The lateral superjunction MOSFET device includes the first column to receive current from the channel when the MOSFET is turned on and to distribute the channel current to the lateral superjunction structure functioning as the drain drift region. In some embodiment, the MOSFET device includes a second column disposed in close proximity to the first column.…

Device structure and manufacturing method using HDP deposited source-body implant block

Granted: July 25, 2017
Patent Number: 9716156
This invention discloses a semiconductor power device. The trenched semiconductor power device includes a trenched gate, opened from a top surface of a semiconductor substrate, surrounded by a source region encompassed in a body region near the top surface above a drain region disposed on a bottom surface of a substrate. The semiconductor power device further includes an implanting-ion block disposed above the top surface on a mesa area next to the body region having a thickness…

Dual trench-gate IGBT structure

Granted: July 18, 2017
Patent Number: 9711631
An IGBT device includes a substrate having a bottom semiconductor layer of a first conductivity type and an upper semiconductor layer of a second conductivity type, at least one first gate formed in a corresponding first trench disposed over the substrate, and a second gate formed in a second trench disposed over the bottom semiconductor layer. The first and second trenches are provided with gate insulators on each side of the trenches and filled with polysilicon. The second trench…

Molded intelligent power module

Granted: July 11, 2017
Patent Number: 9704789
An intelligent power module (IPM) has a first, second, third and fourth die paddles, a first, second, third, fourth, fifth and sixth transistors, a tie bar, a low voltage IC, a high voltage IC, a first, second and third boost diodes, a plurality of leads and a molding encapsulation. The first transistor is attached to the first die paddle. The second transistor is attached to the second die paddle. The third transistor is attached to the third die paddle. The fourth, fifth and sixth…

Power trench MOSFET with improved unclamped inductive switching (UIS) performance and preparation method thereof

Granted: July 11, 2017
Patent Number: 9704948
A trench type power semiconductor device with improved breakdown voltage and UIS performance and a method for preparation the device are disclosed. The trench type power semiconductor device includes a first contact hole formed in a mesa in the active area and a second contact hole formed in a mesa in an active to termination intermediate area, where the first contact hole is deeper and wider than the second contact hole.

Nanotube semiconductor devices

Granted: July 11, 2017
Patent Number: 9704955
Semiconductor devices are formed using a thin epitaxial layer (nanotube) formed on sidewalls of dielectric-filled trenches. In one embodiment, a method for forming a semiconductor device includes forming a first epitaxial layer on sidewalls of trenches and forming second epitaxial layer on the first epitaxial layer where charges in the doped regions along the sidewalls of the first and second trenches achieve charge balance in operation. In another embodiment, the semiconductor device…

Fault tolerant power supply incorporating intelligent gate driver-switch circuit to provide uninterrupted power

Granted: July 11, 2017
Patent Number: 9705395
A fault tolerant power supply system includes at least one load switch configured to connect an input voltage to an output node of the load switch when the load switch is turned on and at least one power channel coupled to the load switch to receive the input voltage. The power channel is configured as a buck converter and includes at least a high-side power switch and a low-side power switch. The fault tolerant power supply system is configured to measure a current flowing through the…

Magnetic stripe data transmission system and method for reliable data transmission and low power consumption

Granted: July 4, 2017
Patent Number: 9697450
A magnetic stripe data transmission (MST) driver and a method for driving the MST are disclosed. The MST driver is configured to transmit magnetic strip data comprising of streams of pulses. The MST driver comprises a pair of high side switches and a pair of low side switches. The pair of high side switches comprises a first switch and a second switch. The pair of low side switches comprises a third switch and a fourth switch. The first, second, third and fourth switches are arranged in…

Lateral PNP bipolar transistor with narrow trench emitter

Granted: July 4, 2017
Patent Number: 9698237
A lateral bipolar transistor includes trench emitter and trench collector regions to form ultra-narrow emitter regions, thereby improving emitter efficiency. The same trench process is used to form the emitter/collector trenches as well as the trench isolation structures so that no additional processing steps are needed to form the trench emitter and collector. In embodiments of the present invention, the trench emitter and trench collector regions may be formed using ion implantation…

Self-aligned contact for trench power MOSFET

Granted: June 27, 2017
Patent Number: 9691863
Embodiments of the present disclosure provide a self-aligned contact for a trench power MOSFET device. The device has a layer of nitride provided over the conductive material in the gate trenches and over portions of mesas between every two adjacent contact structures. Alternatively, the device has an oxide layer over the conductive material in the gate trenches and over portions of mesas between every two adjacent contact structures. It is emphasized that this abstract is provided to…

Method and circuit for detecting short circuit in an asynchronous DC-DC boost converter

Granted: June 20, 2017
Patent Number: 9684326
A simple, cost-effective and efficient short circuit protection with simple routing of the ground on the PCB is achieved in an asynchronous DC-DC boost converter wherein a voltage sensing controller selectively isolates an input power supply to a load in the event of a short circuit. The controller alleviates need for additional components by utilizing the circuit for under voltage lockout protection and the circuit for overvoltage protection to generate signals for detecting short…

Embedded package and method thereof

Granted: June 20, 2017
Patent Number: 9685430
A method of manufacturing an embedded package comprises attaching a plurality of chips on a pre-mold lead frame; forming a first lamination layer on the plurality of chips, the pre-mold lead frame and a plurality of pins; forming a first plurality of vias and a second plurality of vias through the first lamination layer; forming a respective conductive plug of a plurality of conductive plugs by depositing a respective conductive material in each of the first plurality of vias and each of…

Integrated snubber in a single poly MOSFET

Granted: June 20, 2017
Patent Number: 9685435
Aspects of the present disclosure describe MOSFET devices that have snubber circuits. The snubber circuits comprise one or more resistors with a dynamically controllable resistance that is controlled by changes to a gate and/or drain potentials of the one or more MOSFET structures during switching events.

Compact guard ring structure for CMOS integrated circuits

Granted: June 20, 2017
Patent Number: 9685443
An integrated circuit includes an active device formed in a semiconductor layer of a first conductivity type, a first guard ring of the first conductivity type formed in the semiconductor layer surrounding at least part of the active device; a second guard ring of the second conductivity type formed in the semiconductor layer surrounding the first guard ring and the active device and including comprising alternating first well regions of the first conductivity type and the second well…

Diode structures with controlled injection efficiency for fast switching

Granted: June 20, 2017
Patent Number: 9685523
This invention discloses a semiconductor device disposed in a semiconductor substrate. The semiconductor device includes a first semiconductor layer of a first conductivity type on a first major surface. The semiconductor device further includes a second semiconductor layer of a second conductivity type on a second major surface opposite the first major surface. The semiconductor device further includes an injection efficiency controlling buffer layer of a first conductivity type…