• Hämäläinen, Jani Marko Antero
• Kemell, Marianna Leena
• Leskelä, Markku Antero
• Ritala, Mikko
• Costelle, Leila
• Puukilainen, Esa

Abstract

"Iridium thin films have been grown by atomic;layer deposition (ALD) using Ir(acaC)(3) (acac = acetylacetonato), ozone, and molecular hydrogeh as precursors at low temperatures between 165 and 200 degrees C. At this temperature range, iridium oxide film results in a process without H-2. Therefore H-2 had a reducing effect on the film after the oxidizing ozone pulse. On the other hand, methanol was not effective in reducing the oxide film. Ir(acaC)(3) was sublimed at 155 degrees C, which sets the lowest deposition temperature limit of 165 degrees C for the process. Iridium films were successfully deposited on Al2O3 nucleation layers but also directly on bare soda lime glasses and native oxide covered silicon substrates. About 60 nm thick films had resistivities and roughnesses less than 12 mu Omega cm and 1.4 nm, respectively. The films contained <= 2 atom % hydrogen, <= 1 atom % carbon, and 4-7 atom % oxygen as impurities. The Ir films passed the common tape test indicating good adhesion to all tested surfaces. A full Ir coverage over the substrate was obtained with 7 nm thick film."

Topics

• surface
• Carbon
• thin film
• Oxygen
• glass
• glass
• laser emission spectroscopy
• Hydrogen
• Silicon
• lime
• atomic layer deposition
• Iridium