Diode formed of PMOSFET and schottky diodes

摘要

A P-type Metal-Oxide-Semiconductor Field Effect Transistor (PMOSFET) includes a gate, a first source/drain region connected to the gate, and a second source/drain region on an opposite side of the gate than the first source/drain region. A first Schottky diode includes a first anode connected to the first source/drain region, and a first cathode connected to a body of the PMOSFET. A second Schottky diode includes a second anode connected to the second source/drain region, and a second cathode connected to the body of the PMOSFET.

主权项

1. A device comprising:
a semiconductor substrate; an n-type well region in the semiconductor substrate; a P-type Field Effect Transistor (PFET) comprising:
a gate;a first source/drain region electrically connected to the gate;a second source/drain region on an opposite side of the gate than the first source/drain region, the second source/drain region not being electrically connected to the gate; a first Schottky diode comprising:
a first anode connected to the first source/drain region; anda first cathode connected to the n-type well region, the first source/drain region being disposed between at least a portion of the first cathode and a region of the semiconductor substrate directly under the gate; and a second Schottky diode comprising:
a second anode connected to the second source/drain region; anda second cathode connected to the n-type well region, the second source/drain region being disposed between at least a portion of the second cathode and the region of the semiconductor substrate directly under the gate; a heavily doped p-type region; a first metal-containing plate over and contacting a first portion of the n-type well region, and over and connected to the first source/drain region, wherein:
the first metal-containing plate is the first anode of the first Schottky diode;the heavily doped p-type region is in contact with the first metal-containing plate, with the first Schottky diode between the heavily doped p-type region and the first source/drain region; andthe heavily doped p-type region and the first Schottky diode are on a drain side of the PFET; and a second metal-containing plate over and contacting a second portion of the n-type well region, and over and connected to the second source/drain region, wherein the second metal-containing plate is the second anode of the second Schottky diode, and the n-type well region continuously extends from the first metal-containing plate to the second metal-containing plate.