Hollow cathode magnetron deposition of AlN thin films: crystalline structure and morphology

Abstract

A new dc hollow cathode plasma source has been assembled whith a conventional planar magnetron cathode used together with another plane cathode plate to form a hollow cathode cavity. The system comprises two cathode plates of aluminium separated by a distance d, one of them acting as target of the magnetron cathode, the other being an ordinary plate. The discharge anode is a metallic flange of the vacuum chamber. This leads to enhanced ionization in the cathode cavity region and enables the discharge to operate at significantly lower pressures than for a typical planar magnetron configuration. As a consequence, sputtered atoms can reach a substrate with minimum energy loss due to collisions with filling gas atoms. The discharge gas was a mixture of argon and nitrogen. AlN thin films were grown on silicon substrates, at ambient temperature, and characterized with respect to the structure and morphology by XRD and AFM analyses respectively. The structure and roughness of the AlN films were studied as a function of the deposition parameters.

Investigation of Mechanical and Structural Properties of AlN Thin Films Prepared by Mid-Frequency Pulsed Magnetron Sputtering

“…1 shows the XRD patterns of the films. The reflection at 32.42° corresponds to the AlN (100) plane of the hexagonal type wurtzit structure [1,14]. This peak is common for the highly textured similar to a single crystal.…”

V-I curves and plasma parameters in a high density DC glow discharge generated by a current-source

“…For instance, Takechi et al [9] [11] have accomplished discharges at 0.7 Pa of nitrogen-argon mixtures in a 6 litter cylindrical vessel by means of a hollow cathode magnetron plasma source reporting 1 -7×10 16 m -3 densities. The plasma density obtained with our CSC reaches similar values to those of all the mentioned examples.…”

The use of hollow cathodes in deposition processes: A critical review

“…Several groups have reported the presence of Ar 2+ and the increased generation of such ions in the HCD state [160][161][162][163][164][165][166]. The importance of these ions is, firstly, that they are accelerated to higher energies by the cathode sheath, and secondly, when they strike the cathode, they generate approximately four times the number of electrons than singly-charged ions [67,72].…”