2D-mapping of dopant distribution in deep sub micron CMOS devices by electron holography using adapted FIB-preparation
Open Access
- 1 August 2005
- journal article
- research article
- Published by Oxford University Press (OUP) in Microscopy
- Vol. 54 (4), 351-359
- https://doi.org/10.1093/jmicro/dfi055
Abstract
Transmission electron microscopy (TEM) is a widely used tool for analysis of very large scale integrated (VLSI) semiconductor devices. As a special TEM-feature, off-axis electron holography obtains information about the electrical characteristics of a specimen, which are connected to the dopant concentration in the bulk material. Compared with conventional TEM, application of electron holography for dopant profiling demands a higher quality of specimen preparation, e.g. in terms of thickness homogeneity. Since preparation by means of focused ion beam (FIB) has become an industrial standard for TEM-investigations, its facilities are investigated for meeting the high holographic demands. It turned out that, besides many advantages like precision and speed, the use of FIB for preparation introduces new specific problems, e.g. it is hardly possible to visualize doped areas of semiconductors on a classical, thin FIB specimen. Additionally, some artifacts of FIB-preparation have no great importance for normal TEM analysis, but do significantly influence the results of holographic analysis. In order to satisfy the higher demands of preparation for holography, a special procedure for FIB-preparation has been newly developed.Keywords
This publication has 13 references indexed in Scilit:
- Tutorial on Off-Axis Electron HolographyMicroscopy and Microanalysis, 2002
- Measurement of mean free paths for inelastic electron scattering of Si and SiO2.Journal of Electron Microscopy, 2002
- Surface damage formation during ion-beam thinning of samples for transmission electron microscopyUltramicroscopy, 2001
- Two-Dimensional Mapping of the Electrostatic Potential in Transistors by Electron HolographyPhysical Review Letters, 1999
- Applications of Electron HolographyPublished by Springer Science and Business Media LLC ,1999
- Experimental study of amplitude and phase detection limits in electron holographyUltramicroscopy, 1996
- Absolute measurement of normalized thickness, t/λi, from off-axis electron holographyUltramicroscopy, 1994
- Grundlagen der HalbleiterphysikPublished by Springer Science and Business Media LLC ,1970
- Beobachtungen und Messungen an Biprisma-Interferenzen mit ElektronenwellenThe European Physical Journal A, 1956
- A New Microscopic PrincipleNature, 1948