A substrate holder 10 in the form of a mesh structure with a sample-receiving surface 10A is provided. The substrate holder 10 containing the samples 21 is at least partially folded and inserted into a substrate processing apparatus to produce coated samples 21A by directing at least one coating material P1, P2, . . . , Pn onto the samples through the mesh structure. A substrate processing system and a method for producing coated substrates are further provided.