ALUMINUM NITRIDE FILMS PREPARED BY REACTIVE MAGNETRON SPUTTERING

The exceptional properties of aluminium nitride make this material a v ery promising candidate for a variety of technological applications. I n this paper we report our work on the preparation of thin films of al uminium nitride by reactive DC and RF magnetron sputtering. The physic al and electrical properties of the films were studied as a function o f the preparation conditions: concentration of nitrogen in the reactiv e gas mixture, the substrate temperature, the plasma power and the hor izontal distance from the centre of the target. X-ray diffraction data indicated that highly oriented polycrystalline firms could be fabrica ted. Rutherford backscattering and nuclear reaction analysis showed th at nearly stoichiometric films could be prepared using nitrogen concen trations greater than 50%. For the DC plasma process, bombardment of t he growing film plays a very significant role. The film growth mechani sm was found to be very different for the RF plasma. The nuclear analy sis of the films prepared at different lateral distances, together wit h measurements of the substrate potential, permitted modelling of the film formation process for both the DC and RF plasmas.