Optically Controlled Power Devices

Abstract

An electro-optically triggered power switch is disclosed utilizing a wide bandgap, high purity III-nitride semiconductor material such as BN, AN, GaN, InN and their compounds. The device is electro-optically triggered using a laser diode operating at a wavelength of 10 to 50 nanometers off the material's bandgap, and at a power level of 10 to 100 times less than that required in a conventionally triggered device. The disclosed device may be configured as a high power RF MOSFET, IGBT, FET, or HEMT that can be electro-optically controlled using photons rather than an electrical signal. Electro-optic control lowers the power losses in the semiconductor device, decreases the turn-on time, and simplifies the drive signal requirements. It also allows the power devices to be operated from the millisecond to the sub-picosecond timeframe, thus allowing the power device to be operated at RF frequencies (i.e., kilohertz to terahertz range) and at high temperatures where the bandgap changes with temperature.

1 . An electro-optically triggered power device, comprising:
 a semiconductor comprised of a III-nitride material; and   a source of photons, wherein an output beam of said source is coupled to said semiconductor and generates carriers within said semiconductor.   
     
     
         2 . The electro-optically triggered power device of  claim 1 , wherein said source is comprised of a laser diode. 
     
     
         3 . The electro-optically triggered power device of  claim 2 , wherein said output beam is coupled to said semiconductor via an optical fiber. 
     
     
         4 . The electro-optically triggered power device of  claim 1 , wherein said III-nitride material is selected from the group of III-nitride materials consisting of BN, AlN, GaN, InN. 
     
     
         5 . The electro-optically triggered power device of  claim 1 , wherein said semiconductor is undoped and a Franz-Keldysh effect is applied to said semiconductor to alter a photon absorption depth corresponding to said semiconductor, and wherein a wavelength corresponding to said source is between 2 and 150 nanometers below a bandgap corresponding to said semiconductor. 
     
     
         6 . The electro-optically triggered power device of  claim 1 , wherein said semiconductor is undoped and a Franz-Keldysh effect is applied to said semiconductor to alter a photon absorption depth corresponding to said semiconductor, and wherein a wavelength corresponding to said source is between 2 and 150 nanometers above a bandgap corresponding to said semiconductor. 
     
     
         7 . The electro-optically triggered power device of  claim 1 , wherein said semiconductor is doped and a Franz-Keldysh effect is applied to said semiconductor to alter a photon absorption depth corresponding to said semiconductor, and wherein a wavelength corresponding to said source is between 2 and 150 nanometers below a bandgap corresponding to said semiconductor. 
     
     
         8 . The electro-optically triggered power device of  claim 1 , wherein said semiconductor is doped and a Franz-Keldysh effect is applied to said semiconductor to alter a photon absorption depth corresponding to said semiconductor, and wherein a wavelength corresponding to said source is between 2 and 150 nanometers above a bandgap corresponding to said semiconductor. 
     
     
         9 . The electro-optically triggered power device of  claim 1 , said electro-optically triggered power device comprising a transistor. 
     
     
         10 . The electro-optically triggered power device of  claim 1 , said electro-optically triggered power device comprising a SCR structure. 
     
     
         11 . The electro-optically triggered power device of  claim 1 , said electro-optically triggered power device comprising a GTO structure. 
     
     
         12 . The electro-optically triggered power device of  claim 1 , wherein conductivity of said semiconductor varies in direct proportion to an intensity corresponding to said output beam of said source. 
     
     
         13 . The electro-optically triggered power device of  claim 1 , wherein a gate corresponding to said electro-optically triggered power device operates in an avalanche mode. 
     
     
         14 . The electro-optically triggered power device of  claim 1 , wherein said III-nitride material is grown via HVPE. 
     
     
         15 . The electro-optically triggered power device of  claim 1 , further comprising a pair of ohmic contacts coupled to said semiconductor. 
     
     
         16 . The electro-optically triggered power device of  claim 1 , further comprising a pair of Schottky contacts coupled to said semiconductor. 
     
     
         17 . The electro-optically triggered power device of  claim 1 , further comprising a pair of metal contacts coupled to said semiconductor. 
     
     
         18 . The electro-optically triggered power device of  claim 1 , said electro-optically triggered power device having a switching time in the range of a millisecond to less than a picosecond.