Comparison of TiN thin films grown on SiO 2 by reactive dc magnetron sputtering and high power impulse magnetron sputter
- PDF / 209,675 Bytes
- 5 Pages / 432 x 648 pts Page_size
- 5 Downloads / 259 Views
Comparison of TiN thin films grown on SiO2 by reactive dc magnetron sputtering and high power impulse magnetron sputtering F. Magnus1, A. S. Ingason1,2, O. B. Sveinsson1, S. Olafsson1, and J. T. Gudmundsson1,3 1
Science Institute, University of Iceland, Dunhaga 3, IS-107, Reykjavik, Iceland Thin Film Physics, Department of Physics (IFM), Linköping University, Linköping SE-581 83, Sweden 3 UM-SJTU Joint Institute, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai, 200240, China 2
ABSTRACT Thin TiN films were grown on SiO2 by a reactive dc magnetron sputtering (dcMS) and high power impulse magnetron sputtering (HiPIMS) at range of temperatures from 45 to 600oC and the properties compared. The HiPIMS process produces denser films at lower growth temperature than does dcMS and the surface is much smoother for films grown by the HiPIMS process. The grain sizes of both orientations are smaller in HiPIMS grown films than in dcMS grown films. The [200] crystallites have smaller size than the [111] crystallites for all growth temperatures. For the dcMS process the grain size increases with increased growth temperature for both the [111] and [200] crystallites. For the HiPIMS process the [200] grain size increases monotonically with increased growth temperature, whereas the size of the [111] oriented grains decreases to a minimum for growth temperature of 400 oC after which it starts to increase with growth temperature. INTRODUCTION Thin films of sputter deposited TiN have various applications in microelectronics. Its low bulk electrical resistivity, high chemical stability and high melting point make it well suited as an adhesion layer and diffusion barrier for both aluminum and copper interconnects [1,2]. More recently TiN has been suggested as a potential gate metal in metal-oxide-semiconductor (MOS) devices with high-κ gate dielectrics [3]. All of these applications require fully dense films which can be obtained by increasing the deposition temperature or applying a rather high substrate bias, which is not always desired in the fabrication process. High power impulse magnetron sputtering (HiPIMS) is a novel ionized physical vapor deposition (IPVD) technique that has received significant interest lately [4,5]. By pulsing the target to a high power density with low frequency, unipolar voltage pulses, with a low duty cycle, a high electron density is achieved which leads to a high ionization fraction of the sputtered vapor. TiN thin films grown on silicon by reactive HiPIMS show denser microstructure and smoother surfaces as compared to films grown by conventional dc magnetron sputtering at the same average power [6,7]. Lattemann et al. [7] have also reported on fully dense, smooth surface, non-faceted (111)-textured TiN films grown by HiPIMS at ambient temperature without a substrate heater or substrate bias. Here we compare the morphology of TiN thin films grown by dc magnetron sputtering (dcMS) and HiPIMS on thermally oxidized Si (100) substrates. The film crystal structure and grain size was examined ex-sit
Data Loading...
