Correlation Between the V-I Characteristics of (0001) 4H-SiC PN Junctions Having Different Structural Features and Synchrotron X-ray Topography

摘要

We have fabricated 1.5kV class four pn-type junction TEGs (Test Element Groups) of TEG_A, B, C and D having different structural features on the same wafer. The TEG_A consists of one main pn junction as a simple pn diode, while the TEG_B, C and D have p-wells in an active area. In the TEG_D, it includes the n+ region within each p-wells as well. Comparing synchrotron white beam x-ray topography (SWBXT) images with the light emission images in TEG_A, it was suggested that only a small number of TSD (threading screw dislocation) brings fatal deterioration on the breakdown voltage (V_(BD)), and the most of TSDs have less influence. The V_(BD) and fabrication yields of TEG_C and D show a strong correlation with the activation annealing condition for the ion-implanted layer.