What is the definition of a thick film?
It's almost impossible to define in any real sense – it's like defining how long a piece of string is (by the way, it is twice as long as the distance from the middle to one of its ends). This is why there are a multitude of films that use the term ‘thick’.
Thick films occupy a space between thin films and bulk materials, which is why the exact definition of a thick film is difficult to express in a meaningful way. Often in literature 1μm will be quoted as the separation between thin and thick films with little reasoning behind why this should be. Likewise, and for equally arbitrary reasons, 100 μm is often given as the upper limit.
An alternative definition (and one with a physical basis) considers ...