We suggest a technique of fabrication of thick heavily Ga doped by thermomigration layers of Si for modern power electronics devices. Structure perfection and layers composition as a function of formation temperature were studied by techniques of X-ray Lang topography, X-ray rocking curves and secondary ion mass spectrometry. The fabricated layers are single crystalline, no mismatch dislocations were found on the interface with the Si substrate. The Ga concentration in the layers can be varied in the range (1.6-4.8)1019 cm-3, being higher than for Si doping with aluminum.

We have produced through-wafer vertical Si (Ga) p-channels by thermal migration of local gallium zones in c-Si (111) wafers. To achieve this, a method for the formation of local zone was proposed and implemented, which consists in filling linear grooves etched in a silicon wafer with fine-dispersed Ga powder. The grooves were 100 um wide and 30-50um deep. It was shown that a high yield of suitable zones occurs when the grain size of the powder is 5 um and the temperature is 290 K. The obtained Si (Ga) thermomigration p-channels were studied by X-ray methods of double-crystal rocking curves and projection topography. The characterization of structural perfection of Ga p-channels was performed by their comparison with the structural features of the Si (Al) thermomigration channels. Typical structural defects at the boundaries of both thermomigration channels were shown to be dislocation half-loops fixed by their ends at those boundaries. The concentrations of Al and Ga in the obtained channels were estimated as С(Al) ~ 1E19 и С(Ga) ~ 1.9 E19cm-3, the deformation e~(2–5)E-5 and tilt ~ 15–30 ʹʹ of crystal planes near the channel-matrix interface of the plate were determined.