Quickfix-window commands respect the switchbuf option when creating
the buffer. The switchbuf option has the newtab specifier that
instructs Vim to open a new tab page before loading the buffer to
switch to. If one adds this key to the option via
:set switchbuf+=newtab
the entries in the quickfix window will be opened in separate tab
pages.
There is the usetab specifier that also might be useful in this
case. It prescribes Vim to switch to an existing tab page if it
contains a window displaying the target buffer, instead of duplicating
it in a new tab. If it is desirable, one can throw that in, too:
:set switchbuf+=usetab,newtab
The value of switchbuf also (partially) affects other
buffer-switching commands, such as :bfirst, :blast, :sbuffer,
:sbnext, and :sbprevious.