Multi layers of 1-octy1-3-methylimidazolium tetrafluoroborate [C(8)C(1)Im][BF4] have been deposited on a Cu(111) surface by evaporation in UHV. XPS shows that [C(8)C(1)Im][BF4] adsorbs without decomposition for substrate temperatures < 300 K. XPS and UPS data indicate that ionic liquid (IL) deposition onto a 120 K Cu(111) surface results in the IL forming multilayers by a simultaneous-multilayer growth process. IL deposition onto a room temperature Cu(111) surface results in a different arrangement where at a coverage of one monolayer the IL forms droplets of about 100 angstrom height covering only about 1/10th of the surface. Multi layers deposited at 120 K convert to the room temperature arrangement upon heating. Further heating above room temperature causes the IL multilayer droplets to desorb leaving an IL monolayer of approximate to 6 angstrom thickness at approximate to 430 K. At higher temperatures, this monolayer reacts with the surface and BF3 is emitted, leaving products containing C, N, and some F on the surface. We propose a surface reaction where [BF4](-) ions react to form chemisorbed fluorine (Cu-F) and gaseous BF3, with the remaining [C(8)C(1)Im](+) decomposing on the Cu(111) in an unidentified manner.