Radiation Defects Created in n‐Type 4H‐SiC by Electron Irradiation in the Energy Range of 1-10 MeV

Radiation damage produced in 4H–SiC n–epilayers by electrons of different energies is presented. Junction Barrier Schottky power SiC diodes were irradiated with 1.05, 2.1, 5 and 10 MeV electrons with doses up to 600 kGy. Radiation defects are characterized by capacitance deep‐level transient spectroscopy and C‐V measurement. The stability of introduced defects and their effect on carrier lifetime reduction is discussed, as well

Advanced Design of Lifetime Control for High-power Devices in TCAD Environment

At present, advanced design of high-power devices relies on standard TCAD tools. In spite of their maturity, there are many specific areas these tools do not cover satisfactorily and special approach to device design has to be chosen. One of these areas, namely the device parameter optimization via lifetime engineering, is presented. Optimization of both the static and dynamic parameters of the free-wheeling diode supporting operation of the 4.5 kV Gate Turn-Off thyristor is used as an example

Molybdenum and low-temperature annealing of a silicon power P-i-N diode

). The devices were characterized using DLTS, spreading resistance, OCVD lifetime, leakage current, forward voltage drop and reverse recovery measurements. The diffusion of Mo from the 50 nm thick surface layer was not registered even after 4 h between 550 and 800°C in a rough vacuum. The DLTS confirms the existence of hole deep levels H1 and H2 in the He implanted devices with the Mo anode layer. Similar levels have been already found in the devices with Pt and Pd anode layers, but with different annealing behavior between 600 and 700°C. Contrary to that of the Pt and Pd, no radiation enhanced diffusion was found from the 50 nm thick Mo surface layer in a rough vacuum

Radiation Resistance of High-Voltage Silicon and 4H-SiC Power p-i-n Diodes

The different effect of displacement damage produced by neutron irradiation on the static characteristics of 4.5-kV silicon and 4H silicon carbide (SiC) p-i-n power diodes is explained using deep level transient spectroscopy (DLTS), C–V profiling, and open-circuit voltage decay (OCVD) measurements. The number of introduced defects in SiC is higher, also the degradation of carrier lifetime and carrier removal proceeds more swiftly in SiC than those in silicon. However, smaller dimensions and a higher doping level of the n-base of the SiC diode compensate for these negative effects. As a result, the SiC p-i-n diode exhibits substantially higher resistance to neutron irradiation at higher fluences when the diode loses its ON-state carrier modulation capability. SiC also shows a negligible effect of irradiation on leakage current due to the wider bandgap. One may assume a better reliability of SiC bipolar devices over the silicon in a high neutron radiation environment

The Destruction Mechanism in GCTs

This paper focuses on the causes that lead to the final destruction in standard gate-commutated thyristor (GCT) devices. A new 3-D model approach has been used for simulating the GCT which provides a deep insight into the operation of the GCT in extreme conditions. This allows drawing some conclusions on the complex mechanisms that drive these devices to destruction, previously impossible to explain using 2-D models. © 1963-2012 IEEE