/Fopathname
This option specifies an object (.obj) file name or directory to be used instead of the default. If you do not use this option, the object file uses the base name of the source file and the .obj extension. You can use any name and extension you want, but the recommended convention is to use .obj.
The following command line creates an object file named THIS.obj in an existing directory, \OBJECT, on drive B.
CL /FoB:\OBJECT\ THIS.C
Output-File (/F) Options | Compiler Options | Setting Compiler Options | Specifying the Pathname