Thanh Tran¹, Maheshwar Shrestha², Qi Hua Fan^1
1Michigan State University, East Lansing, MI; ²Scion Plasma LLC, East Lansing, MI
Tantalum-doped tin oxide (TTO) is a potential alternative for indium tin oxide (ITO), which is getting more and more expensive, in optoelectronic applications. However, the fabrication of TTO often require high temperatures to get low resistivity and high transparence. In this work, we demonstrate that a treatment using a single beam ion source can produce a highly transparent and conductive TTO film at room temperature. In particular, this work studies RF sputtering of 100 nm TTO thin films by using a TTO target (Sn_(1-x)Ta_xO₂ with x=0.02, 99.99 % purity) at room temperature with the assistance of a soft ion beam of 120 eV by comparing the results with 100 nm TTO films deposited at the same conditions but without ion beam treatment. Broad ranges of oxygen flow are applied to both cases to find optimized results for comparison. The result shows that with a soft ion beam assisted, TTO thin film can have the resistivity as low as 5.8 (mOhm.cm) with an average transmittance of 79 % in the range of 400 nm to 1200 nm. Whereas, in the case of without ion beam assistance, the minimum resistivity is 31.6 (mOhm.cm) with a corresponding average transmittance of 78% in the range of 400 nm to 1200 nm.