I sometimes steam a chicken in the slow cooker, with just a splash of water in the bottom, and you get a surprising amount of stock underneath it when it's done. Really good stock. Sets like a jelly. You also get a lot of rendered fat, especially from a free range chicken. Same happens with ducks and any large joint of meat.
When we're finished eating a chicken, however it was cooked, I take the leftover meat off the bone, then I throw the carcass in the slow cooker and cover with cold water and let it go on High for 3 or 4 hours. (My slow cooker is a Crock Pot brand, and so cooks hot and will bring cold water to a simmer in an hour; if you have a more traditional style slow cooker you may have to let it run overnight to get a good stock). Then I strain it, skim the fat and boil it down so it takes up less space in the freezer.
If there's enough fat, I'll mix it up with twice its weight in flour and a splash of water to make pastry, squash it into a box and freeze it for future pies.
These are my two methods for lazy-person's stock. I never skim the scum or clarify or do any of these things, because I am lazy.
I don't really know what "bone broth" is meant to mean.