Fast recovery diode

1. A fast recovery diode comprising:

an n-doped base layer having a cathode side and an anode side opposite the cathode side;

a p-doped anode layer on the anode side, the anode layer having a doping profile and comprising at least two sublayers, which are arranged parallel to the anode side, wherein:

the at least two sublayers comprise a first sublayer and a last sublayer;

the first sublayer has a first maximum doping concentration, which is between 2*10 16 cm −3 and 2*10 17 cm −3 , the first maximum doping concentration being higher than the maximum doping concentration of any other sublayer of the at least two sublayers;

the last sublayer having a last sublayer depth, which is larger than any other sublayer depth, the last sublayer depth being between 90 to 120 μm;

the doping profile of the anode layer declines such that a doping concentration in a range of 5*10 14 cm −3 and 1*10 15 cm −3 is reached between a first depth, which is at least 20 μm, and a second depth, which is at maximum 50 μm; and

wherein the at least two sublayers are aluminum diffused layers.

2. The diode according to claim 1 , wherein the first depth is at least 30 μm.

3. The diode according to claim 1 , wherein the second depth is at maximum 40 μm.

4. The diode according to claim 1 , wherein the diode has a larger width at the cathode side than at the anode side.

5. The diode according to claim 1 , wherein the diode has a smaller width at the cathode side than at the anode side.

6. The diode according to claim 1 , comprising:

a defect layer having a defect peak, the defect layer being arranged parallel to the anode side with the defect peak in a depth beyond a depth in which the doping concentration of the anode layer is declined below 1*10 15 cm −3 , and smaller than the second depth.

7. A method for manufacturing a fast recovery diode, the method comprising:

providing an n-doped wafer having a cathode side and an anode side opposite the cathode side;

arranging a p-doped anode layer on the anode side, the anode layer having a doping profile and comprising at least two sublayers in the manufactured diode, the at least two sublayers comprising at least a first sublayer and a last sublayer; and

creating each sublayer by applying Aluminum ions on the anode side of the wafer and diffusing the applied Aluminum ions into the wafer to create the corresponding sublayer with a sublayer depth and a maximum doping concentration, respectively, wherein:

the first sublayer is created with a first maximum doping concentration, which is between 2*10 16 cm −3 and 2*10 17 cm −3 and which is higher than the maximum doping concentration of any other sublayer;

the last sublayer is created with a last sublayer depth, which is larger than any other sublayer depth, the last sublayer depth being between 90 to 120 μm; and

the doping concentrations and sublayer depths of the at least two sublayers are such that the doping profile of the anode layer declines to a value in a range of 5*10 14 cm −3 and 1*10 15 cm −3 between a first depth, which is at least 20 μm, and a second depth, which is at maximum 50 μm.

8. The method according to claim 7 , comprising:

irradiating the wafer on the anode side with ions to create a defect layer having a defect peak,

wherein the irradiation energy is such that the defect peak is arranged in a depth beyond a depth in which the doping concentration of the anode layer is declined below 1*10 15 cm −3 , and smaller than the second depth.

9. The method according to claim 8 , wherein the ions for the creation of the defect layer are one of protons and helium.

10. The method according to claim 7 , comprising:

after diffusing the Aluminum ions into the wafer, removing at least a part of the first sublayer which is arranged between the wafer surface on the anode side and the first maximum doping concentration.

11. A device comprising an Integrated Gate Commutated Thyristor and a diode according to claim 1 .

12. The diode according to claim 2 , wherein the second depth is at maximum 40 μm.

13. The diode according to claim 12 , wherein the diode has a larger width at the cathode side than at the anode side.

14. The diode according to claim 12 , wherein the diode has a smaller width at the cathode side than at the anode side.

15. The diode according to claim 13 , comprising:

a defect layer having a defect peak, the defect layer being arranged parallel to the anode side with the defect peak in a depth beyond a depth in which the doping concentration of the anode layer is declined below 1*10 15 cm −3 , and smaller than the second depth.

16. The diode according to claim 14 , comprising:

a defect layer having a defect peak, the defect layer being arranged parallel to the anode side with the defect peak in a depth beyond a depth in which the doping concentration of the anode layer is declined below 1*10 15 cm −3 , and smaller than the second depth.

17. A device comprising an Insulated Gate Bipolar Transistor and a diode according to claim 1 .

18. The method according to claim 7 , comprising:

after diffusing the Aluminum ions into the wafer, completely removing a part of the first sublayer which is arranged between the wafer surface on the anode side and the first maximum doping concentration.