Thank you very much! I could install:
pacman -Qs brother-dcp-9020cdw
local/brother-dcp-9020cdw 1.1.4-2
CUPS driver for the Brother DCP-9020CDW
[micha@zuHause ~]$ pacman -Qs brscan4
local/brscan4 0.4.11_1-2
SANE drivers from Brother for compatible models
I created here a new thread: Scanner doesn´t work