Enhanced aluminum doping profile in 4H-SiC by wet-chemical laser doping

In this paper, enhancement of Aluminum doping profile in semi-insulating 4H-SiC by using Eximer laser in AlCl3 aqueous solution is focused. Several active parameters like number of shots, laser power and dopants solution density affect the doping mechanism. Laser doping with increase of AlCl3 solution concentration from 28 to 36 wt.% results in more efficient doping with merging features like better ohmic contact formation having ideal symmetry factor. Hall Effect measurement using Van der Pauw method show that laser produces a highly doped p-type layer with increasing carrier concentration from 1012/cm2 to a maximum 1015/cm2 by tuning parameter . Current-Voltage characteristics of modified region show the ohmic behavior with reduction in resistance. UV spectrometer absorption tangent line shifts from 375 nm to 401 nm indicating that Al impurity has been introduced in 4H-SiC.