Silicon carbide power devices

Abstract

An embodiment relates to a device comprising a unit cell on a SiC substrate, the unit cell comprising a gate insulator film, a trench in the well region, and a first sinker region of a second conduction type, wherein the first sinker region has a depth that is equal to or greater than a depth of a well region; wherein the device has an on-resistance of less than 3 milliohm-cm2, a gate threshold voltage of greater than 2.8V, a breakdown voltage of greater than 1450V, and an electric field of less than 3.5 megavolt/cm in the gate insulator film at a drain voltage of less than or equal to 1200 V.

1 . A device comprising a unit cell on a SiC substrate, the unit cell comprising:
 a gate insulator film,   a trench in a well region, and   a first sinker region of a second conduction type, wherein the first sinker region has a depth that is equal to or greater than a depth of the well region;   wherein the device has an on-resistance of less than 3 milliohm centimeter squared, a gate threshold voltage of greater than 2.8 Volt, a breakdown voltage of greater than 1450 Volt, and an electric field of less than 3.5 megavolt per cm in the gate insulator film at a drain voltage of less than or equal to 1200 Volt.   
     
     
         2 . The device of  claim 1 , wherein the device comprises a semiconductor metal-insulator-semiconductor transistor component. 
     
     
         3 . The device of  claim 1 , wherein the unit cell further comprises a semiconductor body of a first conduction type that comprises a drift zone; the well region of the second conduction type next to an insulator-semiconductor interface; and a source region of the first conduction type formed within the well region. 
     
     
         4 . The device of  claim 1 , wherein a depth of the trench is greater than or equal to a thickness of the source region. 
     
     
         5 . The device of  claim 1 , wherein the first sinker region is located below the trench. 
     
     
         6 . The device of  claim 1 , further comprising a second sinker region of the second conduction type. 
     
     
         7 . The device of  claim 6 , wherein a depth of the second sinker region is less than a depth of the first sinker region. 
     
     
         8 . The device of  claim 6 , wherein a depth of the second sinker region is greater than a depth of the well region. 
     
     
         9 . A device comprising a unit cell on a SiC substrate, the unit cell comprising:
 a well region, a source region, and a trench, wherein a depth of the trench is greater than a depth of the source region;   wherein the device has an avalanche energy of greater than 14 Joule per centimeter squared, calculated by dividing an avalanche energy in Joules by a total die area in centimeter squared.   
     
     
         10 . The device of  claim 9 , wherein the unit cell further comprises a first sinker region of a second conductivity type, wherein an avalanche failure is located within the unit cell. 
     
     
         11 . A device comprising silicon carbide, the device having a second conductivity type shield region that is outside a junction field-effect transistor region, wherein a doping concentration in a second conductivity type well region within a MOSFET channel is non-uniform;
 wherein the device has a gate threshold voltage of greater than 3.8 Volt, a breakdown voltage of greater than 4100 Volt at a gate to source voltage of 0 Volt, an on-resistance of less than 12 milliohm centimeter squared, an electric field of less than 3.5 megavolt per centimeter at less than or equal to a drain voltage of 3500 Volt, and a short-circuit withstand time of greater than 6 microsecond at a drain voltage of 1500 Volt.   
     
     
         12 . The device of  claim 11 , wherein the second conductivity type shield region is located inside the second conductivity type well region in a manner that a lateral location of a point having a higher doping concentration than that of an average background doping concentration of the second conductivity type well region is positioned within the second conductivity type well region. 
     
     
         13 . The device of  claim 11 , wherein the second conductivity type shield region extends beyond the second conductivity type well region. 
     
     
         14 . The device of  claim 13 , wherein the second conductivity type shield region extends beyond a vertical extent of the second conductivity type well region. 
     
     
         15 . The device of  claim 11 , wherein the device comprises multiple second conductivity type shield regions. 
     
     
         16 . The device of  claim 11 , wherein doping concentration profiles of the second conductivity type shield region in different regions are different. 
     
     
         17 . The device of  claim 11 , wherein doping concentration profiles of the second conductivity type shield region in different regions are not substantially different.