• Vihervaara, Anton
• Leskelä, Markku Antero
• Mizohata, Kenichiro
• Chundak, Mykhailo
• Putkonen, Matti
• Ritala, Mikko
• Li, Xinzhi
• Vehkamäki, Marko

Abstract

This paper presents preparation of boron-doped Al2O3 thin films by atomic layer deposition (ALD) using phenylboronic acid (PBA) and trimethylaluminum (TMA) as precursors. Deposition temperatures of 160-300 degrees C are studied, giving a maximum growth per cycle (GPC) of 0.77 angstrom at 200 degrees C. Field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM) are used to study the surface morphology and roughness of the films. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), Time-of-flight elastic recoil detection analysis (ToF-ERDA), and X-ray photoelectron spectroscopy (XPS) are used to study the composition of the films. An annealing process is carried out at 450 degrees C for 1 h to investigate its effect on the elemental composition and electrical properties of the boron-doped Al2O3 thin films. The boron-doped Al2O3 70 nm thick film deposited at 200 degrees C has a boron content of 3.7 at.% with low leakage current density (10(-9) to 10(-6) A cm(-2)) when the film thickness is 70 nm. The dielectric constant of this boron doped Al2O3 film is 5.18. ; Peer reviewed

Topics

• density
• impedance spectroscopy
• surface
• scanning electron microscopy
• thin film
• x-ray photoelectron spectroscopy
• atomic force microscopy
• dielectric constant
• Boron
• annealing
• current density
• Fourier transform infrared spectroscopy
• atomic layer deposition