Triangular Single Shockley Stacking Fault Analyses on 4H-SiC PiN Diode with Forward Voltage Degradation

Single Shockley stacking fault expansion from immobile basal plane dislocations in 4H-SiC

“…42) In a previous study, the vertical side was analyzed by TEM and HAADF-STEM and was found to be formed from Si-core PDs. 39) The present result is in good agreement with this. Therefore, it is highly probable that the leftmost part in Fig.…”

“…From a previous investigation of a sample with the same structure, the vertical side of the 1SSF triangle was found about 450 nm deep from the surface by cross-sectional BF-TEM observation. 39) The depth of the FIB sampling was determined by combining this vertical side depth with the measured length of the base side of the 1SSF obtained from PL imaging, the off-cut angle of 4°, and the epilayer thickness measured by cross-sectional SEM. Markers were needed in order to increase the precision of the planar location.…”

“…28) Although 1SSF expansion and contraction phenomena have been closely examined experimentally [29][30][31][32][33] analytically, [34][35][36] and theoretically, 37,38) the structure of the PDs that constitute the 1SSF remains to be fully elucidated and demonstrated experimentally, particularly in real power devices such as PiN diodes. 39,40) According to the analytical approach, it has been concluded that the combination of 30 °C-core and 90 °C-core PDs in the BPD produce no expansion. 35) Finding the condition that can form these combinations is therefore a significant issue.…”

Origin and Generation Process of a Triangular Single Shockley Stacking Fault Expanding from the Surface Side in 4H-SiC PIN Diodes

“…The 1SSFs of T1 and T3 had a right-angled corner on the right side, and these two types are the most frequently observed and repo rted. 3,[5][6][7][9][10][11][12][13][14]16,[19][20][21][22] However, the 1SSFs of T2 had a triangular shape with a right-and-left in contrast to T1 and T3. The expansion direction of T2, which was from the surface to the substrate/epilayer interface, was opposite to that of T3.…”

“…7 In addition, many analyses have been conducted of these 1SSFs, including current/temperature stress testing, [8][9][10][11][12][13][14] calculations, [15][16][17][18] and crystal analysis. [19][20][21][22][23] The BPD detection by photoluminescence (PL) imaging and the use of a buffer layer between the substrate and the epitaxial layer was proposed as a method for controlling 1SSF expansion 4,7,11,24 with the aim of solving the V F degradation issue.…”