Hydrogen doping of DC sputtered ZnO:Al films from novel target material

Transparent conducting Al-doped zinc oxide layers have been prepared by pulsed DC sputtering of two different sintered ceramic ZnO alloy targets. From both targets films with resistivities around 690 μΩ cm were obtained. Resistivity could be reduced further by adding hydrogen to the sputtering gas. A decrease of up to 35% was observed with maximum hydrogen flow which is limited by process stability as severe arcing is observed at high hydrogen flows. It was found that hydrogen is incorporated into the film and the carrier concentration increases linearly with hydrogen content. SEM pictures did not reveal major structural changes while slight changes in XRD patterns can be observed.