Use CopyRaster GPTool using format .bsq (band sequential) or .bip (band interleaved by pixel).
These RAW formats mean that the data is output an noncompressed images one pixel after the other. The difference between .bsq and .bip is how the pixels from seperate bands are organized. With these files there is an auxiliary .hdr file that defines the ordering, number of cols,rows, pixel depth etc. I typically would not recommend using. These formats are really only used for interchange to legacy applications that do not support more standard image formats such as TIF. Not these Esri and photoshop raw formats are not the same as 'Camera RAW' formats which are lowest level output from digital cameras. Each camera manufacturer has their own version of camera raw format. Its rare for software to export to these camera raw formats.
