We present an investigation of the structural quality of arrays of 3C-SiC micropillars and microridges grown epitaxially on deeply etched Si(0 0 1) substrates offcut towards [1 1 0]. Using high resolution X-ray diffraction with reciprocal space mapping and optical as well as scanning electron microscopy, we obtain information about the stacking fault (SF) formation in different crystallographic directions. The SF density is strongly correlated with the microcrystal size and orientation and a reduction of the SF density is found in the [1 1 1] and [1-1 1] directions. No variation of the average SF size was detected for varying SiC microcrystal size and shape.