With respect to the studies carried out in August (AFM and profilometer) additional tests were performed using confocal microscopy. The investigations showed that the sample etched in a solution of 8HF:1HNO3:1H2O volume ratio for 60 seconds was characterized by a normal regular surface microstructure consisting of the oval holes ranging in size from a few to tens of micrometers. This means that the resulting structures are considerably higher (approximately twice) than those observed for the wafers etched in the 7:2:1 solution at a the same time. This result can be advantageous from the point of view of the wafers fragility and surface defects etching. The slopes of the resulting holes are smoother while maintaining optimal shape. Holes depth were estimated to a few microns to the maximum of 10.