Increasing the Oxidation Resistance of Molybdenum Thin Films

摘要

Sputter-deposited molybdenum (Mo) films are widely used as electrode layers in various thin film devices such as thin film transistors (TFTs), thin film solar cells, or touch sensors. For special applications the thin films need to withstand excessive exposure to humid atmosphere or ambient air, combined with elevated/high temperatures, without oxidation or corrosion. The stability of Mo against these conditions can be enhanced by adding certain alloying elements (e.g., Ta, Nb, Ti) to the sputtering target. For most applications, it is necessary to pattern the electrode films by wet chemical etching. Typically, the alloying elements reduce not only the rate of corrosion or oxidation but also the wet etch rate, and to identify the right alloying amount is not straightforward. In addition, other film properties like electrical conductivity, residual stress, or adhesion should not be negatively affected.