Solid state thermoelectric energy conversion devices can provide electrical energy from heat flow, creating energy, or inversely, provide cooling through applying energy. Thick film methods are applied to fabricate thermoelectric device structures using microstructures formed through deposition and subsequent thermal processing conditions. An advantageous coincidence of material properties makes possible a wide variety of unique microstructures that are easily applied for the fabrication of device structures in general. As an example, a direct bond process is applied to fabricate thermoelectric semiconductor thick films on substrates by printing and subsequent thermal processing to form unique microstructures which can be densified. Bismuth and antimony are directly bonded to flexible nickel substrates.