Step coverage study of indium-tin-oxide thin films by spray CVD on non-flat substrates at different temperatures

Tin-doped In2O3 (indium-tin-oxide) films were deposited on non-flat Si substrates using an original spray chemical vapor deposition (CVD) system. When the deposition temperature was 300–350 °C, ITO films covered all surfaces (top surface, side walls, and bottom; opening size was 1 μm) after being sprayed 50 times. The step coverage decreased as the number of spray increased because the opening size became smaller due to the layered ITO films, and it therefore became increasingly difficult to supply raw materials. The ITO films could not be deposited when the grooves narrowed to less than 0.18 μm. The step coverage of ITO films clearly increased, although the deposition rate decreased due to the decreasing deposition temperature.