AVS 47th International Symposium
    Material Characterization Friday Sessions
       Session MC+NS-FrM

Paper MC+NS-FrM2
Material and Interface Characterization of Locally Deposited Dielectrics and Metals Fabricated with a Focused Ion Beam (FIB)

Friday, October 6, 2000, 8:40 am, Room 207

Session: Characterization of Interfaces and Thin Films
Presenter: H.D. Wanzenboeck, Vienna University of Technology, Austria
Authors: H.D. Wanzenboeck, Vienna University of Technology, Austria
H. Langfischer, Vienna University of Technology, Austria
E. Bertagnolli, Vienna University of Technology, Austria
H. Stoeri, Vienna University of Technology, Austria
M. Gritsch, Vienna University of Technology, Austria
H. Hutter, Vienna University of Technology, Austria
Correspondent: Click to Email
A chemical vapor deposition process was performed under vacuum conditions utilizing a focused ion beam (FIB) tool confining the deposition on a selected area in the µm down to the deep sub-µm range. The direct fabrication by FIB offers a versatile approach for rapid development and instant testing of novel microelectronic devices. The electrical properties of devices are influenced by the bulk attributes of the material. For complex multilayer structures the interface between 2 materials is of crucial importance. A focused Ga ion beam with diameter down to 5 nm was applied to induce decomposition of selected metalorganic species and siliconorganic compounds adsorbed on the sample surface. Deposition of metals was achieved by using metalcarbonyls such as W(CO)6 as precursors. Dielectrics such as siliconoxides were deposited by coadsorption of siloxane and pure oxygene. For siliconoxide the mixture ratio of the volatile precursor gases was found to be decisive for the chemical composition and electrical properties. For material characterization multilayer structuresof dielectric and metal have been investigated. Auger-Spectroscopy revealed a correlation between the chemical composition of the FIB-deposited layers their electric characteristics and the process parameters chosen. Images of the X-section of the surface and interface deposited layers showed a homogeneous bulk density and a satisfactory surface roughness. Although the interface between FIB-deposited metal and dielectric layer is clearly visible in the secondary electron image depth profiling by secondary ion mass spectroscopy (SIMS) suggests an altered layer due to atomic mixing by the ion beam in a typical range up to 100 nm. The refined comprehension allowed to optimize the process parameters foraer improved material properties.