Evolution of threading screw dislocation conversion during solution growth of 4H-SiC

Abstract

Evolution of threading screw dislocation (TSD) conversion during the solution growth of 4H-SiC on a vicinal crystal of 4H-SiC(0001) was investigated by synchrotron X-ray topography. Selecting appropriate X-ray wavelength and g vector, we can change the penetration of X-ray, and the dislocation behaviors with the different depth were successfully observed. Evidently TSDs parallel to the c-axis having c-component Burgers vector were changed into defects on the (0001) basal planes with the same Burgers vector as the TSDs, propagating to the [112¯0] step-flow direction by advancing macrosteps during the solution growth. The TSD conversions stochastically took place during the growth. The conversion rate was almost uniform and finally almost all TSDs were converted to the basal plane defects. The conversion rate was low at the very early stage of the growth, which implies that the macrosteps were not formed at the initial stage of the solution growth

Effect of aluminum addition on the surface step morphology of 4H–SiC grown from Si–Cr–C solution

“…Several studies have reported significant reduction of threading dislocations during crystal growth [2][3][4][5]. Threading dislocations convert to defects on basal (0001) planes by the interaction between the dislocations and macrostep flow during growth [2][3][4]. Solution growth requires no elaborate procedures, such as "repeated a-face (RAF)" growth reported for the sublimation method [8], to reduce threading dislocations.…”

“…Recently, the study of solution growth has rapidly developed, and it has attracted interest as a growth method for high-quality SiC crystals [1][2][3][4][5][6][7]. Several studies have reported significant reduction of threading dislocations during crystal growth [2][3][4][5].…”

Influence of the growth interface shape on the defect characteristics in the facet region of 4H-SiC single crystals

“…The large surface steps that formed during growth of crystal B visible in Figure 3 lead to the assumption that a mechanism similar to the dislocation conversion utilized in solution growth led to a defect reduction. Using the solution growth method the growth interface typically shows macrosteps formed due to step bunching [9]. The lateral movement of the macrosteps can convert TSDs into defects in the basal plane and therefore lead to an overall reduction of the defect densities [9].…”

“…Using the solution growth method the growth interface typically shows macrosteps formed due to step bunching [9]. The lateral movement of the macrosteps can convert TSDs into defects in the basal plane and therefore lead to an overall reduction of the defect densities [9]. The conversion of TSDs leads to the formation of stacking faults.…”

Structure of basal plane defects formed by the conversion of threading screw dislocation during solution growth of SiC

“…For the SiC power devices with high performance and long-term reliability, high-quality SiC wafers with low-dislocation density are necessary [2]. Solution growth method is one of the methods to produce high-quality SiC wafers [3][4][5][6][7]. Recently we have revealed that threading screw dislocations (TSDs) were converted to basal plane defects during the solution growth of 4H-SiC [5,6].…”