Santana likes the Dorian mode. I learn samba pa ti when I was about 10 from Vee of "Vee and the crocodiles", a port moront cover band that played the Street Festivals in Gy. He played it on the neck. I presently play it at the fifth fret as it fits well over a minor pentatonic scale. I also play it at the 12th.
Santana's melodic phrases are easily to copy but to play them as he does is not as simple. One has to play them santana-like or develop one's own phrasing which is what I do.