Influence of Growth Temperature and Carrier Flux on the Structure and Transport Properties of Highly Oriented CrO2 on Al2O3 (0001)

✍ Scribed by P. M. Sousa; S. A. Dias; O. Conde; A. J. Silvestre; W. R. Branford; B. Morris; K. A. Yates; L. F. Cohen

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 576 KB
• Volume: 13
• Category: Article
• ISSN: 0948-1907
• DOI: 10.1002/cvde.200706592

✦ Synopsis

In this work we report on the structure and magnetic and electrical transport properties of CrO 2 films deposited onto (0001) sapphire by atmospheric pressure (AP)CVD from a CrO 3 precursor. Films are grown within a broad range of deposition temperatures, from 320 to 410 °C, and oxygen carrier gas flow rates of 50-500 sccm, showing that it is viable to grow highly oriented a-axis CrO 2 films at temperatures as low as 330 °C i.e., 60-70 °C lower than is reported in published data for the same chemical system. Depending on the experimental conditions, growth kinetic regimes dominated either by surface reaction or by mass-transport mechanisms are identified. The growth of a Cr 2 O 3 interfacial layer as an intrinsic feature of the deposition process is studied and discussed. Films synthesized at 330 °C keep the same high quality magnetic and transport properties as those deposited at higher temperatures.