Integrated freewheeling diode and extraction device

Abstract

A Freewheeling Diode of any kind (Fast Recovery Diode, Schottky Barrier Diode or other variants) is integrated with a Forced Extraction Device and in this way two entirely different functions—the Free-Wheeling function and the Forced Extraction function are combined in one device, simplifying the circuit and reducing the number of components. The FWD part of the integrated device is standard in the industry, but the Forced Extraction Device is made using a lateral or vertical PMOS with a voltage capability between a control input and the output terminals that is as high or higher than the rating voltage of the Main Switch that will be used together with the FWD.

What is claimed is: 
     
         1 . A semiconductor device formed on a semiconductor substrate, the semiconductor having a first, second, third, and fourth terminals, the semiconductor device comprising:
 a freewheeling diode coupled between the first and second terminals; and   an Extraction Device structured to be coupled to a conductivity modulation switch device through the third terminal, the Extraction Device further coupled to the second terminal and the fourth terminal.   
     
     
         2 . The semiconductor device according to  claim 1 , in which the first terminal is a ground terminal, the second terminal is an output terminal, the third terminal is an extraction terminal, and the fourth terminal is a control input terminal. 
     
     
         3 . The semiconductor device according to  claim 2 , in which, when the Extraction Device is turned on, the Extraction Device is structured to create a conduction path between the extraction terminal and the output terminal. 
     
     
         4 . The semiconductor device according to  claim 1 , in which the semiconductor substrate is formed of Silicon or formed of a wide-bandgap material. 
     
     
         5 . The semiconductor device according to  claim 1 , in which the freewheeling diode is a PIN diode, Schottky diode, or merged PN-Schottky structure or any type of freewheeling diode. 
     
     
         6 . The semiconductor device according to  claim 1 , in which the Extraction Device includes a PMOS transistor formed with a thick gate oxide that has a voltage blocking capacity that is in excess of a blocking voltage capacity of any conductivity modulation switch device to which the Extraction Device is connected. 
     
     
         7 . The semiconductor device according to  claim 6 , in which the PMOS transistor is a lateral transistor or a vertical transistor. 
     
     
         8 . The semiconductor device according to  claim 2 , further comprising a capacitor coupled in series between the control terminal and the Extraction Device. 
     
     
         9 . The semiconductor device according to  claim 2 , in which the extraction terminal is coupled to an extraction plug of the conductivity modulation switch device. 
     
     
         10 . A semiconductor device employing conductivity modulation and being voltage controlled, formed on a semiconductor substrate, the semiconductor device comprising:
 a power semiconductor switch having a drift region in the semiconductor substrate, and having a gate for controlling operation of the power semiconductor switch, the power semiconductor switch further including an input and an output;   an Extraction Plug in electrical contact with the drift region of the power semiconductor switch, the Extraction Plug separated from the power semiconductor switch by a voltage blocking termination;   an Extraction Device having a control gate electrically coupled to the gate of the power semiconductor switch, and structured to be controlled by a same control signal that controls operation of the power semiconductor switch, the Extraction Device further electrically coupled to the Extraction Plug and structured to remove charge carriers from the drift region through the Extraction Plug when the power semiconductor switch is turned off; and   a freewheeling diode coupled in parallel to the power semiconductor switch.   
     
     
         11 . The semiconductor device according to  claim 10 , in which an anode of the freewheeling diode is coupled to the ground terminal of the power semiconductor switch, and in which a cathode of the freewheeling diode is coupled to the output of the power semiconductor switch. 
     
     
         12 . A semiconductor module, comprising:
 a first semiconductor substrate including:
 a power semiconductor switch having a drift region in the semiconductor substrate, and having a gate for controlling operation of the power semiconductor switch, the power semiconductor switch further including a ground and an output, and 
 an Extraction Plug in electrical contact with the drift region of the power semiconductor switch, the Extraction Plug separated from the power semiconductor switch by a voltage blocking termination; and 
   a second semiconductor electrically connected to the first semiconductor substrate, the second semiconductor substrate including:
 an Extraction Device having a control gate electrically coupled to the gate of the power semiconductor switch, and structured to be controlled by a same control signal that controls operation of the power semiconductor switch, the Extraction Device further electrically coupled to the Extraction Plug and structured to remove charge carriers from the drift region through the Extraction Plug when the power semiconductor switch is turned off, and 
 a freewheeling diode coupled in parallel to the power semiconductor switch. 
   
     
     
         13 . The semiconductor module according to  claim 12 , in which the second semiconductor substrate is formed of Silicon or formed of a wide-bandgap material. 
     
     
         14 . The semiconductor module according to  claim 13 , in which the wide-bandgap material comprises diamond, Ga 2 O 3 , GaN, or SiC. 
     
     
         15 . The semiconductor module according to  claim 12 , in which the freewheeling diode is a PIN diode, Schottky diode, merged PN-Schottky structure, or any type of freewheeling diode. 
     
     
         16 . The semiconductor module according to  claim 12 , in which the Extraction Device includes a PMOS transistor formed with a thick gate oxide that has a voltage blocking capacity that is in excess of a blocking voltage capacity of the power semiconductor switch. 
     
     
         17 . The semiconductor module according to  claim 15 , in which the PMOS transistor is a lateral transistor or a vertical transistor. 
     
     
         18 . The semiconductor module according to  claim 12 , further comprising a capacitor coupled to the control gate of the Extraction Device and in which the same control signal that controls operation of the power semiconductor switch is applied to the capacitor.